Programs & Examples On #Powershell

PowerShell is a command line and scripting utility for Windows. Use this tag for questions about writing and executing PowerShell scripts ONLY. Programming questions specific to the cross-platform version PowerShell Core (Windows, macOS, Linux) should be tagged [powershell-core]. Questions about system administration should be asked on SuperUser.

PowerShell and the -contains operator

You can use like:

"12-18" -like "*-*"

Or split for contains:

"12-18" -split "" -contains "-"

How to print a certain line of a file with PowerShell?

This will show the 10th line of myfile.txt:

get-content myfile.txt | select -first 1 -skip 9

both -first and -skip are optional parameters, and -context, or -last may be useful in similar situations.

Running PowerShell as another user, and launching a script

Here's also nice way to achieve this via UI.

0) Right click on PowerShell icon when on task bar

1) Shift + right click on Windows PowerShell

2) "Run as different user"

Pic

How to use the curl command in PowerShell?

In Powershell 3.0 and above there is both a Invoke-WebRequest and Invoke-RestMethod. Curl is actually an alias of Invoke-WebRequest in PoSH. I think using native Powershell would be much more appropriate than curl, but it's up to you :).

Invoke-WebRequest MSDN docs are here: https://technet.microsoft.com/en-us/library/hh849901.aspx?f=255&MSPPError=-2147217396

Invoke-RestMethod MSDN docs are here: https://technet.microsoft.com/en-us/library/hh849971.aspx?f=255&MSPPError=-2147217396

How to export a CSV to Excel using Powershell

I am using excelcnv.exe to convert csv into xlsx and that seemed to work properly. You will have to change the directory to where your excelcnv is. If 32 bit, it goes to Program Files (x86)

Start-Process -FilePath 'C:\Program Files\Microsoft Office\root\Office16\excelcnv.exe' -ArgumentList "-nme -oice ""$xlsFilePath"" ""$xlsToxlsxPath"""

Redirection of standard and error output appending to the same log file

Andy gave me some good pointers, but I wanted to do it in an even cleaner way. Not to mention that with the 2>&1 >> method PowerShell complained to me about the log file being accessed by another process, i.e. both stderr and stdout trying to lock the file for access, I guess. So here's how I worked it around.

First let's generate a nice filename, but that's really just for being pedantic:

$name = "sync_common"
$currdate = get-date -f yyyy-MM-dd
$logfile = "c:\scripts\$name\log\$name-$currdate.txt"

And here's where the trick begins:

start-transcript -append -path $logfile

write-output "starting sync"
robocopy /mir /copyall S:\common \\10.0.0.2\common 2>&1 | Write-Output
some_other.exe /exeparams 2>&1 | Write-Output
...
write-output "ending sync"

stop-transcript

With start-transcript and stop-transcript you can redirect ALL output of PowerShell commands to a single file, but it doesn't work correctly with external commands. So let's just redirect all the output of those to the stdout of PS and let transcript do the rest.

In fact, I have no idea why the MS engineers say they haven't fixed this yet "due to the high cost and technical complexities involved" when it can be worked around in such a simple way.

Either way, running every single command with start-process is a huge clutter IMHO, but with this method, all you gotta do is append the 2>&1 | Write-Output code to each line which runs external commands.

How to output something in PowerShell

I think the following is a good exhibit of Echo vs. Write-Host. Notice how test() actually returns an array of ints, not a single int as one could easily be led to believe.

function test {
    Write-Host 123
    echo 456 # AKA 'Write-Output'
    return 789
}

$x = test

Write-Host "x of type '$($x.GetType().name)' = $x"

Write-Host "`$x[0] = $($x[0])"
Write-Host "`$x[1] = $($x[1])"

Terminal output of the above:

123
x of type 'Object[]' = 456 789
$x[0] = 456
$x[1] = 789

Loop X number of times

Here is a simple way to loop any number of times in PowerShell.

It is the same as the for loop above, but much easier to understand for newer programmers and scripters. It uses a range, and foreach. A range is defined as:

range = lower..upper

or

$range = 1..10

A range can be used directly in a for loop as well, although not the most optimal approach, any performance loss or additional instruction to process would be unnoticeable. The solution is below:

foreach($i in 1..10){
    Write-Host $i
}

Or in your case:

$ActiveCampaigns = 10
foreach($i in 1..$ActiveCampaigns)
{
    Write-Host $i
    If($i==$ActiveCampaigns){
        // Do your stuff on the last iteration here
    }
}

How to get the current directory of the cmdlet being executed

To expand on @Cradle 's answer: you could also write a multi-purpose function that will get you the same result per the OP's question:

Function Get-AbsolutePath {

    [CmdletBinding()]
    Param(
        [parameter(
            Mandatory=$false,
            ValueFromPipeline=$true
        )]
        [String]$relativePath=".\"
    )

    if (Test-Path -Path $relativePath) {
        return (Get-Item -Path $relativePath).FullName -replace "\\$", ""
    } else {
        Write-Error -Message "'$relativePath' is not a valid path" -ErrorId 1 -ErrorAction Stop
    }

}

Ignore 'Security Warning' running script from command line

You want to set the execution policy on your machine using Set-ExecutionPolicy:

Set-ExecutionPolicy Unrestricted

You may want to investigate the various execution policies to see which one is right for you. Take a look at the "help about_signing" for more information.

Connect to SQL Server Database from PowerShell

Integrated Security and User ID \ Password authentication are mutually exclusive. To connect to SQL Server as the user running the code, remove User ID and Password from your connection string:

$SqlConnection.ConnectionString = "Server = $SQLServer; Database = $SQLDBName; Integrated Security = True;"

To connect with specific credentials, remove Integrated Security:

$SqlConnection.ConnectionString = "Server = $SQLServer; Database = $SQLDBName; User ID = $uid; Password = $pwd;"

What exactly is "exit" in PowerShell?

It's a reserved keyword (like return, filter, function, break).

Reference

Also, as per Section 7.6.4 of Bruce Payette's Powershell in Action:

But what happens when you want a script to exit from within a function defined in that script? ... To make this easier, Powershell has the exit keyword.

Of course, as other have pointed out, it's not hard to do what you want by wrapping exit in a function:

PS C:\> function ex{exit}
PS C:\> new-alias ^D ex

The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)

My problem turned out to be blank spaces in the txt file that I was using to feed the WMI Powershell script.

VSCode Change Default Terminal

You can also select your default terminal by pressing F1 in VS Code and typing/selecting Terminal: Select Default Shell.

Terminal Selection

Terminal Selection

Import pfx file into particular certificate store from command line

For Windows 10:

Import certificate to Trusted Root Certification Authorities for Current User:

certutil -f -user -p oracle -importpfx root "example.pfx"

Import certificate to Trusted People for Current User:

certutil -f -user -p oracle -importpfx TrustedPeople "example.pfx"

Import certificate to Trusted Root Certification Authorities on Local Machine:

certutil -f -user -p oracle -enterprise -importpfx root "example.pfx"

Import certificate to Trusted People on Local Machine:

certutil -f -user -p oracle -enterprise -importpfx TrustedPeople "example.pfx"

Removing duplicate values from a PowerShell array

This is how you get unique from an array with two or more properties. The sort is vital and the key to getting it to work correctly. Otherwise you just get one item returned.

PowerShell Script:

$objects = @(
    [PSCustomObject] @{ Message = "1"; MachineName = "1" }
    [PSCustomObject] @{ Message = "2"; MachineName = "1" }
    [PSCustomObject] @{ Message = "3"; MachineName = "1" }
    [PSCustomObject] @{ Message = "4"; MachineName = "1" }
    [PSCustomObject] @{ Message = "5"; MachineName = "1" }
    [PSCustomObject] @{ Message = "1"; MachineName = "2" }
    [PSCustomObject] @{ Message = "2"; MachineName = "2" }
    [PSCustomObject] @{ Message = "3"; MachineName = "2" }
    [PSCustomObject] @{ Message = "4"; MachineName = "2" }
    [PSCustomObject] @{ Message = "5"; MachineName = "2" }
    [PSCustomObject] @{ Message = "1"; MachineName = "1" }
    [PSCustomObject] @{ Message = "2"; MachineName = "1" }
    [PSCustomObject] @{ Message = "3"; MachineName = "1" }
    [PSCustomObject] @{ Message = "4"; MachineName = "1" }
    [PSCustomObject] @{ Message = "5"; MachineName = "1" }
    [PSCustomObject] @{ Message = "1"; MachineName = "2" }
    [PSCustomObject] @{ Message = "2"; MachineName = "2" }
    [PSCustomObject] @{ Message = "3"; MachineName = "2" }
    [PSCustomObject] @{ Message = "4"; MachineName = "2" }
    [PSCustomObject] @{ Message = "5"; MachineName = "2" }
)

Write-Host "Sorted on both properties with -Unique" -ForegroundColor Yellow
$objects | Sort-Object -Property Message,MachineName -Unique | Out-Host

Write-Host "Sorted on just Message with -Unique" -ForegroundColor Yellow
$objects | Sort-Object -Property Message -Unique | Out-Host

Write-Host "Sorted on just MachineName with -Unique" -ForegroundColor Yellow
$objects | Sort-Object -Property MachineName -Unique | Out-Host

Output:

Sorted on both properties with -Unique

Message MachineName
------- -----------
1       1          
1       2          
2       1          
2       2          
3       1          
3       2          
4       1          
4       2          
5       1          
5       2          


Sorted on just Message with -Unique

Message MachineName
------- -----------
1       1          
2       1          
3       1          
4       1          
5       2          


Sorted on just MachineName with -Unique

Message MachineName
------- -----------
1       1          
3       2  

Source: https://powershell.org/forums/topic/need-to-unique-based-on-multiple-properties/

Changing PowerShell's default output encoding to UTF-8

Note: The following applies to Windows PowerShell.
See the next section for the cross-platform PowerShell Core (v6+) edition.

  • On PSv5.1 or higher, where > and >> are effectively aliases of Out-File, you can set the default encoding for > / >> / Out-File via the $PSDefaultParameterValues preference variable:

    • $PSDefaultParameterValues['Out-File:Encoding'] = 'utf8'
  • On PSv5.0 or below, you cannot change the encoding for > / >>, but, on PSv3 or higher, the above technique does work for explicit calls to Out-File.
    (The $PSDefaultParameterValues preference variable was introduced in PSv3.0).

  • On PSv3.0 or higher, if you want to set the default encoding for all cmdlets that support
    an -Encoding parameter
    (which in PSv5.1+ includes > and >>), use:

    • $PSDefaultParameterValues['*:Encoding'] = 'utf8'

If you place this command in your $PROFILE, cmdlets such as Out-File and Set-Content will use UTF-8 encoding by default, but note that this makes it a session-global setting that will affect all commands / scripts that do not explicitly specify an encoding via their -Encoding parameter.

Similarly, be sure to include such commands in your scripts or modules that you want to behave the same way, so that they indeed behave the same even when run by another user or a different machine; however, to avoid a session-global change, use the following form to create a local copy of $PSDefaultParameterValues:

  • $PSDefaultParameterValues = @{ '*:Encoding' = 'utf8' }

Caveat: PowerShell, as of v5.1, invariably creates UTF-8 files _with a (pseudo) BOM_, which is customary only in the Windows world - Unix-based utilities do not recognize this BOM (see bottom); see this post for workarounds that create BOM-less UTF-8 files.

For a summary of the wildly inconsistent default character encoding behavior across many of the Windows PowerShell standard cmdlets, see the bottom section.


The automatic $OutputEncoding variable is unrelated, and only applies to how PowerShell communicates with external programs (what encoding PowerShell uses when sending strings to them) - it has nothing to do with the encoding that the output redirection operators and PowerShell cmdlets use to save to files.


Optional reading: The cross-platform perspective: PowerShell Core:

PowerShell is now cross-platform, via its PowerShell Core edition, whose encoding - sensibly - defaults to BOM-less UTF-8, in line with Unix-like platforms.

  • This means that source-code files without a BOM are assumed to be UTF-8, and using > / Out-File / Set-Content defaults to BOM-less UTF-8; explicit use of the utf8 -Encoding argument too creates BOM-less UTF-8, but you can opt to create files with the pseudo-BOM with the utf8bom value.

  • If you create PowerShell scripts with an editor on a Unix-like platform and nowadays even on Windows with cross-platform editors such as Visual Studio Code and Sublime Text, the resulting *.ps1 file will typically not have a UTF-8 pseudo-BOM:

    • This works fine on PowerShell Core.
    • It may break on Windows PowerShell, if the file contains non-ASCII characters; if you do need to use non-ASCII characters in your scripts, save them as UTF-8 with BOM.
      Without the BOM, Windows PowerShell (mis)interprets your script as being encoded in the legacy "ANSI" codepage (determined by the system locale for pre-Unicode applications; e.g., Windows-1252 on US-English systems).
  • Conversely, files that do have the UTF-8 pseudo-BOM can be problematic on Unix-like platforms, as they cause Unix utilities such as cat, sed, and awk - and even some editors such as gedit - to pass the pseudo-BOM through, i.e., to treat it as data.

    • This may not always be a problem, but definitely can be, such as when you try to read a file into a string in bash with, say, text=$(cat file) or text=$(<file) - the resulting variable will contain the pseudo-BOM as the first 3 bytes.

Inconsistent default encoding behavior in Windows PowerShell:

Regrettably, the default character encoding used in Windows PowerShell is wildly inconsistent; the cross-platform PowerShell Core edition, as discussed in the previous section, has commendably put and end to this.

Note:

  • The following doesn't aspire to cover all standard cmdlets.

  • Googling cmdlet names to find their help topics now shows you the PowerShell Core version of the topics by default; use the version drop-down list above the list of topics on the left to switch to a Windows PowerShell version.

  • As of this writing, the documentation frequently incorrectly claims that ASCII is the default encoding in Windows PowerShell - see this GitHub docs issue.


Cmdlets that write:

Out-File and > / >> create "Unicode" - UTF-16LE - files by default - in which every ASCII-range character (too) is represented by 2 bytes - which notably differs from Set-Content / Add-Content (see next point); New-ModuleManifest and Export-CliXml also create UTF-16LE files.

Set-Content (and Add-Content if the file doesn't yet exist / is empty) uses ANSI encoding (the encoding specified by the active system locale's ANSI legacy code page, which PowerShell calls Default).

Export-Csv indeed creates ASCII files, as documented, but see the notes re -Append below.

Export-PSSession creates UTF-8 files with BOM by default.

New-Item -Type File -Value currently creates BOM-less(!) UTF-8.

The Send-MailMessage help topic also claims that ASCII encoding is the default - I have not personally verified that claim.

Start-Transcript invariably creates UTF-8 files with BOM, but see the notes re -Append below.

Re commands that append to an existing file:

>> / Out-File -Append make no attempt to match the encoding of a file's existing content. That is, they blindly apply their default encoding, unless instructed otherwise with -Encoding, which is not an option with >> (except indirectly in PSv5.1+, via $PSDefaultParameterValues, as shown above). In short: you must know the encoding of an existing file's content and append using that same encoding.

Add-Content is the laudable exception: in the absence of an explicit -Encoding argument, it detects the existing encoding and automatically applies it to the new content.Thanks, js2010. Note that in Windows PowerShell this means that it is ANSI encoding that is applied if the existing content has no BOM, whereas it is UTF-8 in PowerShell Core.

This inconsistency between Out-File -Append / >> and Add-Content, which also affects PowerShell Core, is discussed in this GitHub issue.

Export-Csv -Append partially matches the existing encoding: it blindly appends UTF-8 if the existing file's encoding is any of ASCII/UTF-8/ANSI, but correctly matches UTF-16LE and UTF-16BE.
To put it differently: in the absence of a BOM, Export-Csv -Append assumes UTF-8 is, whereas Add-Content assumes ANSI.

Start-Transcript -Append partially matches the existing encoding: It correctly matches encodings with BOM, but defaults to potentially lossy ASCII encoding in the absence of one.


Cmdlets that read (that is, the encoding used in the absence of a BOM):

Get-Content and Import-PowerShellDataFile default to ANSI (Default), which is consistent with Set-Content.
ANSI is also what the PowerShell engine itself defaults to when it reads source code from files.

By contrast, Import-Csv, Import-CliXml and Select-String assume UTF-8 in the absence of a BOM.

PowerShell array initialization

$array = 1..5 | foreach { $false }

Powershell equivalent of bash ampersand (&) for forking/running background processes

You can use PowerShell job cmdlets to achieve your goals.

There are 6 job related cmdlets available in PowerShell.

  • Get-Job
    • Gets Windows PowerShell background jobs that are running in the current session
  • Receive-Job
    • Gets the results of the Windows PowerShell background jobs in the current session
  • Remove-Job
    • Deletes a Windows PowerShell background job
  • Start-Job
    • Starts a Windows PowerShell background job
  • Stop-Job
    • Stops a Windows PowerShell background job
  • Wait-Job
    • Suppresses the command prompt until one or all of the Windows PowerShell background jobs running in the session are complete

If interesting about it, you can download the sample How to create background job in PowerShell

How to export data to CSV in PowerShell?

This solution creates a psobject and adds each object to an array, it then creates the csv by piping the contents of the array through Export-CSV.

$results = @()
foreach ($computer in $computerlist) {
    if((Test-Connection -Cn $computer -BufferSize 16 -Count 1 -ea 0 -quiet))
    {
        foreach ($file in $REMOVE) {
            Remove-Item "\\$computer\$DESTINATION\$file" -Recurse
            Copy-Item E:\Code\powershell\shortcuts\* "\\$computer\$DESTINATION\"            
        }
    } else {

        $details = @{            
                Date             = get-date              
                ComputerName     = $Computer                 
                Destination      = $Destination 
        }                           
        $results += New-Object PSObject -Property $details  
    }
}
$results | export-csv -Path c:\temp\so.csv -NoTypeInformation

If you pipe a string object to a csv you will get its length written to the csv, this is because these are properties of the string, See here for more information.

This is why I create a new object first.

Try the following:

write-output "test" | convertto-csv -NoTypeInformation

This will give you:

"Length"
"4"

If you use the Get-Member on Write-Output as follows:

write-output "test" | Get-Member -MemberType Property

You will see that it has one property - 'length':

   TypeName: System.String

Name   MemberType Definition
----   ---------- ----------
Length Property   System.Int32 Length {get;}

This is why Length will be written to the csv file.


Update: Appending a CSV Not the most efficient way if the file gets large...

$csvFileName = "c:\temp\so.csv"
$results = @()
if (Test-Path $csvFileName)
{
    $results += Import-Csv -Path $csvFileName
}
foreach ($computer in $computerlist) {
    if((Test-Connection -Cn $computer -BufferSize 16 -Count 1 -ea 0 -quiet))
    {
        foreach ($file in $REMOVE) {
            Remove-Item "\\$computer\$DESTINATION\$file" -Recurse
            Copy-Item E:\Code\powershell\shortcuts\* "\\$computer\$DESTINATION\"            
        }
    } else {

        $details = @{            
                Date             = get-date              
                ComputerName     = $Computer                 
                Destination      = $Destination 
        }                           
        $results += New-Object PSObject -Property $details  
    }
}
$results | export-csv -Path $csvFileName -NoTypeInformation

How can I split a text file using PowerShell?

Same as all the answers here, but using StreamReader/StreamWriter to split on new lines (line by line, instead of trying to read the whole file into memory at once). This approach can split big files in the fastest way I know of.

Note: I do very little error checking, so I can't guarantee it'll work smoothly for your case. It did for mine (1.7 GB TXT file of 4 million lines split in 100,000 lines per file in 95 seconds).

#split test
$sw = new-object System.Diagnostics.Stopwatch
$sw.Start()
$filename = "C:\Users\Vincent\Desktop\test.txt"
$rootName = "C:\Users\Vincent\Desktop\result"
$ext = ".txt"

$linesperFile = 100000#100k
$filecount = 1
$reader = $null
try{
    $reader = [io.file]::OpenText($filename)
    try{
        "Creating file number $filecount"
        $writer = [io.file]::CreateText("{0}{1}.{2}" -f ($rootName,$filecount.ToString("000"),$ext))
        $filecount++
        $linecount = 0

        while($reader.EndOfStream -ne $true) {
            "Reading $linesperFile"
            while( ($linecount -lt $linesperFile) -and ($reader.EndOfStream -ne $true)){
                $writer.WriteLine($reader.ReadLine());
                $linecount++
            }

            if($reader.EndOfStream -ne $true) {
                "Closing file"
                $writer.Dispose();

                "Creating file number $filecount"
                $writer = [io.file]::CreateText("{0}{1}.{2}" -f ($rootName,$filecount.ToString("000"),$ext))
                $filecount++
                $linecount = 0
            }
        }
    } finally {
        $writer.Dispose();
    }
} finally {
    $reader.Dispose();
}
$sw.Stop()

Write-Host "Split complete in " $sw.Elapsed.TotalSeconds "seconds"

Output splitting a 1.7 GB file:

...
Creating file number 45
Reading 100000
Closing file
Creating file number 46
Reading 100000
Closing file
Creating file number 47
Reading 100000
Closing file
Creating file number 48
Reading 100000
Split complete in  95.6308289 seconds

Connecting to a network folder with username/password in Powershell

At first glance one really wants to use New-PSDrive supplying it credentials.

> New-PSDrive -Name P -PSProvider FileSystem -Root \\server\share -Credential domain\user

Fails!

New-PSDrive : Cannot retrieve the dynamic parameters for the cmdlet. Dynamic parameters for NewDrive cannot be retrieved for the 'FileSystem' provider. The provider does not support the use of credentials. Please perform the operation again without specifying credentials.

The documentation states that you can provide a PSCredential object but if you look closer the cmdlet does not support this yet. Maybe in the next version I guess.

Therefore you can either use net use or the WScript.Network object, calling the MapNetworkDrive function:

$net = new-object -ComObject WScript.Network
$net.MapNetworkDrive("u:", "\\server\share", $false, "domain\user", "password")

Edit for New-PSDrive in PowerShell 3.0

Apparently with newer versions of PowerShell, the New-PSDrive cmdlet works to map network shares with credentials!

New-PSDrive -Name P -PSProvider FileSystem -Root \\Server01\Public -Credential user\domain -Persist

Get remote registry value

another option ... needs remoting ...

(invoke-command -ComputerName mymachine -ScriptBlock {Get-ItemProperty HKLM:\SOFTWARE\VanDyke\VShell\License -Name Version }).version

Get startup type of Windows service using PowerShell

In PowerShell you can use the command Set-Service:

Set-Service -Name Winmgmt -StartupType Manual

I haven't found a PowerShell command to view the startup type though. One would assume that the command Get-Service would provide that, but it doesn't seem to.

Why is my locally-created script not allowed to run under the RemoteSigned execution policy?

Is the file being blocked? I had the same issue and was able to resolve it by right clicking the .PS1 file, Properties and choosing Unblock.

Get Folder Size from Windows Command Line

So here is a solution for both your requests in the manner you originally asked for. It will give human readability filesize without the filesize limits everyone is experiencing. Compatible with Win Vista or newer. XP only available if Robocopy is installed. Just drop a folder on this batch file or use the better method mentioned below.

@echo off
setlocal enabledelayedexpansion
set "vSearch=Files :"

For %%i in (%*) do (
    set "vSearch=Files :"
    For /l %%M in (1,1,2) do ( 
        for /f "usebackq tokens=3,4 delims= " %%A in (`Robocopy "%%i" "%%i" /E /L /NP /NDL /NFL ^| find "!vSearch!"`) do (
            if /i "%%M"=="1" (
                set "filecount=%%A"
                set "vSearch=Bytes :"
            ) else (
                set "foldersize=%%A%%B"
            )
        )
    )
    echo Folder: %%~nxi FileCount: !filecount! Foldersize: !foldersize!
    REM remove the word "REM" from line below to output to txt file
    REM echo Folder: %%~nxi FileCount: !filecount! Foldersize: !foldersize!>>Folder_FileCountandSize.txt
)
pause

To be able to use this batch file conveniently put it in your SendTo folder. This will allow you to right click a folder or selection of folders, click on the SendTo option, and then select this batch file.

To find the SendTo folder on your computer simplest way is to open up cmd then copy in this line as is.

explorer C:\Users\%username%\AppData\Roaming\Microsoft\Windows\SendTo

Executing a command stored in a variable from PowerShell

Try invoking your command with Invoke-Expression:

Invoke-Expression $cmd1

Here is a working example on my machine:

$cmd = "& 'C:\Program Files\7-zip\7z.exe' a -tzip c:\temp\test.zip c:\temp\test.txt"
Invoke-Expression $cmd

iex is an alias for Invoke-Expression so you could do:

iex $cmd1

For a full list : Visit https://ss64.com/ps/ for more Powershell stuff.

Good Luck...

Creating and throwing new exception

To call a specific exception such as FileNotFoundException use this format

if (-not (Test-Path $file)) 
{
    throw [System.IO.FileNotFoundException] "$file not found."
}

To throw a general exception use the throw command followed by a string.

throw "Error trying to do a task"

When used inside a catch, you can provide additional information about what triggered the error

Change directory in PowerShell

Set-Location -Path 'Q:\MyDir'

In PowerShell cd = Set-Location

Powershell Invoke-WebRequest Fails with SSL/TLS Secure Channel

If, like me, none of the above quite works, it might be worth also specifically trying a lower TLS version alone. I had tried both of the following, but didn't seem to solve my problem:

[Net.ServicePointManager]::SecurityProtocol = "tls12, tls11, tls"
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12 -bor [Net.SecurityProtocolType]::Tls11 -bor [Net.SecurityProtocolType]::Tls

In the end, it was only when I targetted TLS 1.0 (specifically remove 1.1 and 1.2 in the code) that it worked:

[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls

The local server (that this was being attempted on) is fine with TLS 1.2, although the remote server (which was previously "confirmed" as fine for TLS 1.2 by a 3rd party) seems not to be.

Hope this helps someone.

What does $_ mean in PowerShell?

This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.

1,2,3 | %{ write-host $_ } 

or

1,2,3 | %{ write-host $PSItem } 

For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current value.

Unix tail equivalent command in Windows Powershell

I used some of the answers given here but just a heads up that

Get-Content -Path Yourfile.log -Tail 30 -Wait 

will chew up memory after awhile. A colleague left such a "tail" up over the last day and it went up to 800 MB. I don't know if Unix tail behaves the same way (but I doubt it). So it's fine to use for short term applications, but be careful with it.

How to create a zip archive with PowerShell?

Install 7zip (or download the command line version instead) and use this PowerShell method:

function create-7zip([String] $aDirectory, [String] $aZipfile){
    [string]$pathToZipExe = "$($Env:ProgramFiles)\7-Zip\7z.exe";
    [Array]$arguments = "a", "-tzip", "$aZipfile", "$aDirectory", "-r";
    & $pathToZipExe $arguments;
}

You can the call it like this:

create-7zip "c:\temp\myFolder" "c:\temp\myFolder.zip"

How to find the Windows version from the PowerShell command line

I took the scripts above and tweaked them a little to come up with this:

$name=(Get-WmiObject Win32_OperatingSystem).caption
$bit=(Get-WmiObject Win32_OperatingSystem).OSArchitecture

$vert = " Version:"
$ver=(Get-ItemProperty "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion").ReleaseId

$buildt = " Build:"
$build= (Get-ItemProperty "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion").BuildLabEx -match '^[0-9]+\.[0-9]+' |  % { $matches.Values }

$installd = Get-ComputerInfo -Property WindowsInstallDateFromRegistry

Write-host $installd
Write-Host $name, $bit, $vert, $ver, `enter code here`$buildt, $build, $installd

To get a result like this:

Microsoft Windows 10 Home 64-bit Version: 1709 Build: 16299.431 @{WindowsInstallDateFromRegistry=18-01-01 2:29:11 AM}

Hint: I'd appreciate a hand stripping the prefix text from the install date so I can replace it with a more readable header.

IIS: Display all sites and bindings in PowerShell

Try this:

Import-Module Webadministration
Get-ChildItem -Path IIS:\Sites

It should return something that looks like this:

Name             ID   State      Physical Path                  Bindings
----             --   -----      -------------                  --------
ChristophersWeb 22   Started    C:\temp             http *:8080:ChristophersWebsite.ChDom.com

From here you can refine results, but be careful. A pipe to the select statement will not give you what you need. Based on your requirements I would build a custom object or hashtable.

A better way to check if a path exists or not in PowerShell

If you just want an alternative to the cmdlet syntax, specifically for files, use the File.Exists() .NET method:

if(![System.IO.File]::Exists($path)){
    # file with path $path doesn't exist
}

If, on the other hand, you want a general purpose negated alias for Test-Path, here is how you should do it:

# Gather command meta data from the original Cmdlet (in this case, Test-Path)
$TestPathCmd = Get-Command Test-Path
$TestPathCmdMetaData = New-Object System.Management.Automation.CommandMetadata $TestPathCmd

# Use the static ProxyCommand.GetParamBlock method to copy 
# Test-Path's param block and CmdletBinding attribute
$Binding = [System.Management.Automation.ProxyCommand]::GetCmdletBindingAttribute($TestPathCmdMetaData)
$Params  = [System.Management.Automation.ProxyCommand]::GetParamBlock($TestPathCmdMetaData)

# Create wrapper for the command that proxies the parameters to Test-Path 
# using @PSBoundParameters, and negates any output with -not
$WrappedCommand = { 
    try { -not (Test-Path @PSBoundParameters) } catch { throw $_ }
}

# define your new function using the details above
$Function:notexists = '{0}param({1}) {2}' -f $Binding,$Params,$WrappedCommand

notexists will now behave exactly like Test-Path, but always return the opposite result:

PS C:\> Test-Path -Path "C:\Windows"
True
PS C:\> notexists -Path "C:\Windows"
False
PS C:\> notexists "C:\Windows" # positional parameter binding exactly like Test-Path
False

As you've already shown yourself, the opposite is quite easy, just alias exists to Test-Path:

PS C:\> New-Alias exists Test-Path
PS C:\> exists -Path "C:\Windows"
True

PowerShell: Comparing dates

Late but more complete answer in point of getting the most advanced date from $Output

## Q:\test\2011\02\SO_5097125.ps1
## simulate object input with a here string 
$Output = @"
"Date"
"Monday, April 08, 2013 12:00:00 AM"
"Friday, April 08, 2011 12:00:00 AM"
"@ -split '\r?\n' | ConvertFrom-Csv

## use Get-Date and calculated property in a pipeline
$Output | Select-Object @{n='Date';e={Get-Date $_.Date}} |
    Sort-Object Date | Select-Object -Last 1 -Expand Date

## use Get-Date in a ForEach-Object
$Output.Date | ForEach-Object{Get-Date $_} |
    Sort-Object | Select-Object -Last 1

## use [datetime]::ParseExact
## the following will only work if your locale is English for day, month day abbrev.
$Output.Date | ForEach-Object{
    [datetime]::ParseExact($_,'dddd, MMMM dd, yyyy hh:mm:ss tt',$Null)
} | Sort-Object | Select-Object -Last 1

## for non English locales
$Output.Date | ForEach-Object{
    [datetime]::ParseExact($_,'dddd, MMMM dd, yyyy hh:mm:ss tt',[cultureinfo]::InvariantCulture)
} | Sort-Object | Select-Object -Last 1

## in case the day month abbreviations are in other languages, here German
## simulate object input with a here string 
$Output = @"
"Date"
"Montag, April 08, 2013 00:00:00"
"Freidag, April 08, 2011 00:00:00"
"@ -split '\r?\n' | ConvertFrom-Csv
$CIDE = New-Object System.Globalization.CultureInfo("de-DE")
$Output.Date | ForEach-Object{
    [datetime]::ParseExact($_,'dddd, MMMM dd, yyyy HH:mm:ss',$CIDE)
} | Sort-Object | Select-Object -Last 1

Catching FULL exception message

Errors and exceptions in PowerShell are structured objects. The error message you see printed on the console is actually a formatted message with information from several elements of the error/exception object. You can (re-)construct it yourself like this:

$formatstring = "{0} : {1}`n{2}`n" +
                "    + CategoryInfo          : {3}`n" +
                "    + FullyQualifiedErrorId : {4}`n"
$fields = $_.InvocationInfo.MyCommand.Name,
          $_.ErrorDetails.Message,
          $_.InvocationInfo.PositionMessage,
          $_.CategoryInfo.ToString(),
          $_.FullyQualifiedErrorId

$formatstring -f $fields

If you just want the error message displayed in your catch block you can simply echo the current object variable (which holds the error at that point):

try {
  ...
} catch {
  $_
}

If you need colored output use Write-Host with a formatted string as described above:

try {
  ...
} catch {
  ...
  Write-Host -Foreground Red -Background Black ($formatstring -f $fields)
}

With that said, usually you don't want to just display the error message as-is in an exception handler (otherwise the -ErrorAction Stop would be pointless). The structured error/exception objects provide you with additional information that you can use for better error control. For instance you have $_.Exception.HResult with the actual error number. $_.ScriptStackTrace and $_.Exception.StackTrace, so you can display stacktraces when debugging. $_.Exception.InnerException gives you access to nested exceptions that often contain additional information about the error (top level PowerShell errors can be somewhat generic). You can unroll these nested exceptions with something like this:

$e = $_.Exception
$msg = $e.Message
while ($e.InnerException) {
  $e = $e.InnerException
  $msg += "`n" + $e.Message
}
$msg

In your case the information you want to extract seems to be in $_.ErrorDetails.Message. It's not quite clear to me if you have an object or a JSON string there, but you should be able to get information about the types and values of the members of $_.ErrorDetails by running

$_.ErrorDetails | Get-Member
$_.ErrorDetails | Format-List *

If $_.ErrorDetails.Message is an object you should be able to obtain the message string like this:

$_.ErrorDetails.Message.message

otherwise you need to convert the JSON string to an object first:

$_.ErrorDetails.Message | ConvertFrom-Json | Select-Object -Expand message

Depending what kind of error you're handling, exceptions of particular types might also include more specific information about the problem at hand. In your case for instance you have a WebException which in addition to the error message ($_.Exception.Message) contains the actual response from the server:

PS C:\> $e.Exception | Get-Member

   TypeName: System.Net.WebException

Name             MemberType Definition
----             ---------- ----------
Equals           Method     bool Equals(System.Object obj), bool _Exception.E...
GetBaseException Method     System.Exception GetBaseException(), System.Excep...
GetHashCode      Method     int GetHashCode(), int _Exception.GetHashCode()
GetObjectData    Method     void GetObjectData(System.Runtime.Serialization.S...
GetType          Method     type GetType(), type _Exception.GetType()
ToString         Method     string ToString(), string _Exception.ToString()
Data             Property   System.Collections.IDictionary Data {get;}
HelpLink         Property   string HelpLink {get;set;}
HResult          Property   int HResult {get;}
InnerException   Property   System.Exception InnerException {get;}
Message          Property   string Message {get;}
Response         Property   System.Net.WebResponse Response {get;}
Source           Property   string Source {get;set;}
StackTrace       Property   string StackTrace {get;}
Status           Property   System.Net.WebExceptionStatus Status {get;}
TargetSite       Property   System.Reflection.MethodBase TargetSite {get;}

which provides you with information like this:

PS C:\> $e.Exception.Response

IsMutuallyAuthenticated : False
Cookies                 : {}
Headers                 : {Keep-Alive, Connection, Content-Length, Content-T...}
SupportsHeaders         : True
ContentLength           : 198
ContentEncoding         :
ContentType             : text/html; charset=iso-8859-1
CharacterSet            : iso-8859-1
Server                  : Apache/2.4.10
LastModified            : 17.07.2016 14:39:29
StatusCode              : NotFound
StatusDescription       : Not Found
ProtocolVersion         : 1.1
ResponseUri             : http://www.example.com/
Method                  : POST
IsFromCache             : False

Since not all exceptions have the exact same set of properties you may want to use specific handlers for particular exceptions:

try {
  ...
} catch [System.ArgumentException] {
  # handle argument exceptions
} catch [System.Net.WebException] {
  # handle web exceptions
} catch {
  # handle all other exceptions
}

If you have operations that need to be done regardless of whether an error occured or not (cleanup tasks like closing a socket or a database connection) you can put them in a finally block after the exception handling:

try {
  ...
} catch {
  ...
} finally {
  # cleanup operations go here
}

Delete files older than 15 days using PowerShell

#----- Define parameters -----#
#----- Get current date ----#
$Now = Get-Date
$Days = "15" #----- define amount of days ----#
$Targetfolder = "C:\Logs" #----- define folder where files are located ----#
$Extension = "*.log" #----- define extension ----#
$Lastwrite = $Now.AddDays(-$Days)

#----- Get files based on lastwrite filter and specified folder ---#
$Files = Get-Children $Targetfolder -include $Extension -Recurse | where {$_.LastwriteTime -le "$Lastwrite"}

foreach ($File in $Files)
{
    if ($File -ne $Null)
    {
        write-host "Deleting File $File" backgroundcolor "DarkRed"
        Remove-item $File.Fullname | out-null
    }
    else
        write-host "No more files to delete" -forgroundcolor "Green"
    }
}

How do I get total physical memory size using PowerShell without WMI?

If you don't want to use WMI, I can suggest systeminfo.exe. But, there may be a better way to do that.

(systeminfo | Select-String 'Total Physical Memory:').ToString().Split(':')[1].Trim()

Extract the filename from a path

Find a file using wildcard and getting filename:

Resolve-Path "Package.1.0.191.*.zip" | Split-Path -leaf

How do I start PowerShell from Windows Explorer?

The following is a concise (and updated) summation of the earlier solutions. Here's what to do:

Add these strings and their respective parent keys:

pwrshell\(Default) < Open PowerShell Here
pwrshell\command\(Default) < powershell -NoExit -Command Set-Location -LiteralPath '%V'
pwrshelladmin\(Default) < Open PowerShell (Admin)
pwrshelladmin\command\(Default) < powershell -Command Start-Process -verb runAs -ArgumentList '-NoExit','cd','%V' powershell

at these locations

HKCR\Directory\shell (for folders)
HKCR\Directory\Background\shell (Explorer window)
HKCR\Drive\shell (for root drives)

That's it. Add the "Extended" strings for the commands only to be visible if you hold the "Shift" key, everything else is superfluous.

The term 'ng' is not recognized as the name of a cmdlet

Also you can run following command to resolve, npm install -g @angular/cli

How can I verify if an AD account is locked?

This ScriptingGuy guest post links to a script by a Microsoft Powershell Expert can help you find this information, but to fully audit why it was locked and which machine triggered the lock you probably need to turn on additional levels of auditing via GPO.

https://gallery.technet.microsoft.com/scriptcenter/Get-LockedOutLocation-b2fd0cab#content

Test if registry value exists

This works for me:

Function Test-RegistryValue 
{
    param($regkey, $name)
    $exists = Get-ItemProperty "$regkey\$name" -ErrorAction SilentlyContinue
    Write-Host "Test-RegistryValue: $exists"
    if (($exists -eq $null) -or ($exists.Length -eq 0))
    {
        return $false
    }
    else
    {
        return $true
    }
}

Try/catch does not seem to have an effect

In my case, it was because I was only catching specific types of exceptions:

try
  {
    get-item -Force -LiteralPath $Path -ErrorAction Stop

    #if file exists
    if ($Path -like '\\*') {$fileType = 'n'}  #Network
    elseif ($Path -like '?:\*') {$fileType = 'l'} #Local
    else {$fileType = 'u'} #Unknown File Type

  }
catch [System.UnauthorizedAccessException] {$fileType = 'i'} #Inaccessible
catch [System.Management.Automation.ItemNotFoundException]{$fileType = 'x'} #Doesn't Exist

Added these to handle additional the exception causing the terminating error, as well as unexpected exceptions

catch [System.Management.Automation.DriveNotFoundException]{$fileType = 'x'} #Doesn't Exist
catch {$fileType='u'} #Unknown

PowerShell equivalent to grep -f

This question already has an answer, but I just want to add that in Windows there is Windows Subsystem for Linux WSL.

So for example if you want to check if you have service named Elasicsearch that is in status running you can do something like the snippet below in powershell

net start | grep Elasticsearch

If strings starts with in PowerShell

$Group is an object, but you will actually need to check if $Group.samaccountname.StartsWith("string").

Change $Group.StartsWith("S_G_") to $Group.samaccountname.StartsWith("S_G_").

how do I loop through a line from a csv file in powershell

A slightly other way of iterating through each column of each line of a CSV-file would be

$path = "d:\scratch\export.csv"
$csv = Import-Csv -path $path

foreach($line in $csv)
{ 
    $properties = $line | Get-Member -MemberType Properties
    for($i=0; $i -lt $properties.Count;$i++)
    {
        $column = $properties[$i]
        $columnvalue = $line | Select -ExpandProperty $column.Name

        # doSomething $column.Name $columnvalue 
        # doSomething $i $columnvalue 
    }
} 

so you have the choice: you can use either $column.Name to get the name of the column, or $i to get the number of the column

How to split a string content into an array of strings in PowerShell?

[string[]]$recipients = $address.Split('; ',[System.StringSplitOptions]::RemoveEmptyEntries)

Is there a PowerShell "string does not contain" cmdlet or syntax?

If $arrayofStringsNotInterestedIn is an [array] you should use -notcontains:

Get-Content $FileName | foreach-object { `
   if ($arrayofStringsNotInterestedIn -notcontains $_) { $) }

or better (IMO)

Get-Content $FileName | where { $arrayofStringsNotInterestedIn -notcontains $_}

Is there a way to make a PowerShell script work by double clicking a .ps1 file?

  1. Navigate REGEDIT to HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Microsoft.PowerShellScript.1\Shell
  2. On the right pane, double-click "(Default)"
  3. Delete existing value of "Open" (which launches Notepad) and type "0" (being zero, which launches Powershell directly).

Revert the value if you wish to use Notepad as the default again.

How to unzip a file in Powershell?

ForEach Loop processes each ZIP file located within the $filepath variable

    foreach($file in $filepath)
    {
        $zip = $shell.NameSpace($file.FullName)
        foreach($item in $zip.items())
        {
            $shell.Namespace($file.DirectoryName).copyhere($item)
        }
        Remove-Item $file.FullName
    }

How to make an authenticated web request in Powershell?

In some case NTLM authentication still won't work if given the correct credential.

There's a mechanism which will void NTLM auth within WebClient, see here for more information: System.Net.WebClient doesn't work with Windows Authentication

If you're trying above answer and it's still not working, follow the above link to add registry to make the domain whitelisted.

Post this here to save other's time ;)

How to run an application as "run as administrator" from the command prompt?

Try this:

runas.exe /savecred /user:administrator "%sysdrive%\testScripts\testscript1.ps1" 

It saves the password the first time and never asks again. Maybe when you change the administrator password you will be prompted again.

How to stop a PowerShell script on the first error?

$ErrorActionPreference = "Stop" will get you part of the way there (i.e. this works great for cmdlets).

However for EXEs you're going to need to check $LastExitCode yourself after every exe invocation and determine whether that failed or not. Unfortunately I don't think PowerShell can help here because on Windows, EXEs aren't terribly consistent on what constitutes a "success" or "failure" exit code. Most follow the UNIX standard of 0 indicating success but not all do. Check out the CheckLastExitCode function in this blog post. You might find it useful.

How to quietly remove a directory with content in PowerShell

To delete content without a folder you can use the following:

Remove-Item "foldertodelete\*" -Force -Recurse

Upload file to SFTP using PowerShell

There isn't currently a built-in PowerShell method for doing the SFTP part. You'll have to use something like psftp.exe or a PowerShell module like Posh-SSH.

Here is an example using Posh-SSH:

# Set the credentials
$Password = ConvertTo-SecureString 'Password1' -AsPlainText -Force
$Credential = New-Object System.Management.Automation.PSCredential ('root', $Password)

# Set local file path, SFTP path, and the backup location path which I assume is an SMB path
$FilePath = "C:\FileDump\test.txt"
$SftpPath = '/Outbox'
$SmbPath = '\\filer01\Backup'

# Set the IP of the SFTP server
$SftpIp = '10.209.26.105'

# Load the Posh-SSH module
Import-Module C:\Temp\Posh-SSH

# Establish the SFTP connection
$ThisSession = New-SFTPSession -ComputerName $SftpIp -Credential $Credential

# Upload the file to the SFTP path
Set-SFTPFile -SessionId ($ThisSession).SessionId -LocalFile $FilePath -RemotePath $SftpPath

#Disconnect all SFTP Sessions
Get-SFTPSession | % { Remove-SFTPSession -SessionId ($_.SessionId) }

# Copy the file to the SMB location
Copy-Item -Path $FilePath -Destination $SmbPath

Some additional notes:

  • You'll have to download the Posh-SSH module which you can install to your user module directory (e.g. C:\Users\jon_dechiro\Documents\WindowsPowerShell\Modules) and just load using the name or put it anywhere and load it like I have in the code above.
  • If having the credentials in the script is not acceptable you'll have to use a credential file. If you need help with that I can update with some details or point you to some links.
  • Change the paths, IPs, etc. as needed.

That should give you a decent starting point.

How to run a PowerShell script

If you want to run a script without modifying the default script execution policy, you can use the bypass switch when launching Windows PowerShell.

powershell [-noexit] -executionpolicy bypass -File <Filename>

How to load assemblies in PowerShell?

Most people know by now that System.Reflection.Assembly.LoadWithPartialName is deprecated, but it turns out that Add-Type -AssemblyName Microsoft.VisualBasic does not behave much better than LoadWithPartialName:

Rather than make any attempt to parse your request in the context of your system, [Add-Type] looks at a static, internal table to translate the "partial name" to a "full name".

If your "partial name" doesn't appear in their table, your script will fail.

If you have multiple versions of the assembly installed on your computer, there is no intelligent algorithm to choose between them. You are going to get whichever one appears in their table, probably the older, outdated one.

If the versions you have installed are all newer than the obsolete one in the table, your script will fail.

Add-Type has no intelligent parser of "partial names" like .LoadWithPartialNames.

What Microsoft's .Net teams says you're actually supposed to do is something like this:

Add-Type -AssemblyName 'Microsoft.VisualBasic, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'

Or, if you know the path, something like this:

Add-Type -Path 'C:\WINDOWS\Microsoft.Net\assembly\GAC_MSIL\Microsoft.VisualBasic\v4.0_10.0.0.0__b03f5f7f11d50a3a\Microsoft.VisualBasic.dll'

That long name given for the assembly is known as the strong name, which is both unique to the version and the assembly, and is also sometimes known as the full name.

But this leaves a couple questions unanswered:

  1. How do I determine the strong name of what's actually being loaded on my system with a given partial name?

    [System.Reflection.Assembly]::LoadWithPartialName($TypeName).Location; [System.Reflection.Assembly]::LoadWithPartialName($TypeName).FullName;

These should also work:

Add-Type -AssemblyName $TypeName -PassThru | Select-Object -ExpandProperty Assembly | Select-Object -ExpandProperty FullName -Unique
  1. If I want my script to always use a specific version of a .dll but I can't be certain of where it's installed, how do I determine what the strong name is from the .dll?

    [System.Reflection.AssemblyName]::GetAssemblyName($Path).FullName;

Or:

Add-Type $Path -PassThru | Select-Object -ExpandProperty Assembly | Select-Object -ExpandProperty FullName -Unique
  1. If I know the strong name, how do I determine the .dll path?

    [Reflection.Assembly]::Load('Microsoft.VisualBasic, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a').Location;

  2. And, on a similar vein, if I know the type name of what I'm using, how do I know what assembly it's coming from?

    [Reflection.Assembly]::GetAssembly([Type]).Location [Reflection.Assembly]::GetAssembly([Type]).FullName

  3. How do I see what assemblies are available?

I suggest the GAC PowerShell module. Get-GacAssembly -Name 'Microsoft.SqlServer.Smo*' | Select Name, Version, FullName works pretty well.

  1. How can I see the list that Add-Type uses?

This is a bit more complex. I can describe how to access it for any version of PowerShell with a .Net reflector (see the update below for PowerShell Core 6.0).

First, figure out which library Add-Type comes from:

Get-Command -Name Add-Type | Select-Object -Property DLL

Open the resulting DLL with your reflector. I've used ILSpy for this because it's FLOSS, but any C# reflector should work. Open that library, and look in Microsoft.Powershell.Commands.Utility. Under Microsoft.Powershell.Commands, there should be AddTypeCommand.

In the code listing for that, there is a private class, InitializeStrongNameDictionary(). That lists the dictionary that maps the short names to the strong names. There's almost 750 entries in the library I've looked at.

Update: Now that PowerShell Core 6.0 is open source. For that version, you can skip the above steps and see the code directly online in their GitHub repository. I can't guarantee that that code matches any other version of PowerShell, however.

Update 2: Powershell 7+ does not appear to have the hash table lookup any longer. Instead they use a LoadAssemblyHelper() method which the comments call "the closest approximation possible" to LoadWithPartialName. Basically, they do this:

loadedAssembly = Assembly.Load(new AssemblyName(assemblyName));

Now, the comments also say "users can just say Add-Type -AssemblyName Forms (instead of System.Windows.Forms)". However, that's not what I see in Powershell v7.0.3 on Windows 10 2004.

# Returns an error
Add-Type -AssemblyName Forms

# Returns an error
[System.Reflection.Assembly]::Load([System.Reflection.AssemblyName]::new('Forms'))

# Works fine
Add-Type -AssemblyName System.Windows.Forms

# Works fine
[System.Reflection.Assembly]::Load([System.Reflection.AssemblyName]::new('System.Windows.Forms'))

So the comments appear to be a bit of a mystery.

I don't know exactly what the logic is in Assembly.Load(AssemblyName) when there is no version or public key token specified. I would expect that this has many of the same problems that LoadWithPartialName does like potentially loading the wrong version of the assembly if you have multiple installed.

PowerShell: how to grep command output?

Try this:

PS C:\> ipconfig /displaydns | Select-String -Pattern 'www.yahoo.com' -Context 0,7

>     www.yahoo.com
      ----------------------------------------
>     Record Name . . . . . : www.yahoo.com
      Record Type . . . . . : 5
      Time To Live  . . . . : 27
      Data Length . . . . . : 8
      Section . . . . . . . : Answer
      CNAME Record  . . . . : new-fp-shed.wg1.b.yahoo.com

How do I execute a PowerShell script automatically using Windows task scheduler?

You can use the Unblock-File cmdlet to unblock the execution of this specific script. This prevents you doing any permanent policy changes which you may not want due to security concerns.

Unblock-File path_to_your_script

Source: Unblock-File

Run PowerShell command from command prompt (no ps1 script)

Maybe powershell -Command "Get-AppLockerFileInformation....."

Take a look at powershell /?

Why powershell does not run Angular commands?

script1.ps1 cannot be loaded because running scripts is disabled on this system. For more information, see about_Execution_Policies at http://go.microsoft.com/fwlink/?LinkID=135170

This error happens due to a security measure which won't let scripts be executed on your system without you having approved of it. You can do so by opening up a powershell with administrative rights (search for powershell in the main menu and select Run as administrator from the context menu) and entering:

set-executionpolicy remotesigned

Read Excel sheet in Powershell

There is the possibility of making something really more cool!

# Powershell 
$xl = new-object -ComObject excell.application
$doc=$xl.workbooks.open("Filepath")
$doc.Sheets.item(1).rows |
% { ($_.value2 | Select-Object -first 3 | Select-Object -last 2) -join "," }

Import-CSV and Foreach

Solution is to change Delimiter.

Content of the csv file -> Note .. Also space and , in value

Values are 6 Dutch word aap,noot,mies,Piet, Gijs, Jan

Col1;Col2;Col3

a,ap;noo,t;mi es

P,iet;G ,ijs;Ja ,n



$csv = Import-Csv C:\TejaCopy.csv -Delimiter ';' 

Answer:

Write-Host $csv
@{Col1=a,ap; Col2=noo,t; Col3=mi es} @{Col1=P,iet; Col2=G ,ijs; Col3=Ja ,n}

It is possible to read a CSV file and use other Delimiter to separate each column.

It worked for my script :-)

How do I convert an array object to a string in PowerShell?

You could specify type like this:

[string[]] $a = "This", "Is", "a", "cat"

Checking the type:

$a.GetType()

Confirms:

    IsPublic IsSerial Name                                     BaseType
    -------- -------- ----                                     --------
    True     True     String[]                                 System.Array

Outputting $a:

PS C:\> $a 
This 
Is 
a 
cat

Executing an EXE file using a PowerShell script

In the Powershell, cd to the .exe file location. For example:

cd C:\Users\Administrators\Downloads

PS C:\Users\Administrators\Downloads> & '.\aaa.exe'

The installer pops up and follow the instruction on the screen.

How to redirect the output of a PowerShell to a file during its execution

Maybe Start-Transcript would work for you. First stop it if it's already running, then start it, and stop it when done.

$ErrorActionPreference="SilentlyContinue"
Stop-Transcript | out-null
$ErrorActionPreference = "Continue"
Start-Transcript -path C:\output.txt -append
# Do some stuff
Stop-Transcript

You can also have this running while working on stuff and have it saving your command line sessions for later reference.

If you want to completely suppress the error when attempting to stop a transcript that is not transcribing, you could do this:

$ErrorActionPreference="SilentlyContinue"
Stop-Transcript | out-null
$ErrorActionPreference = "Continue" # or "Stop"

What's the better (cleaner) way to ignore output in PowerShell?

There is also the Out-Null cmdlet, which you can use in a pipeline, for example, Add-Item | Out-Null.

Manual page for Out-Null

NAME
    Out-Null

SYNOPSIS
    Deletes output instead of sending it to the console.


SYNTAX
    Out-Null [-inputObject <psobject>] [<CommonParameters>]


DETAILED DESCRIPTION
    The Out-Null cmdlet sends output to NULL, in effect, deleting it.


RELATED LINKS
    Out-Printer
    Out-Host
    Out-File
    Out-String
    Out-Default

REMARKS
     For more information, type: "get-help Out-Null -detailed".
     For technical information, type: "get-help Out-Null -full".

ErrorActionPreference and ErrorAction SilentlyContinue for Get-PSSessionConfiguration

Tip #2

Can't you use the classical 2> redirection operator.

(Get-PSSessionConfiguration -Name "MyShellUri" -ErrorAction SilentlyContinue) 2> $NULL
if(!$?){
   'foo'
}

I don't like errors so I avoid them at all costs.

Removing path and extension from filename in PowerShell

Expanding on René Nyffenegger's answer, for those who do not have access to PowerShell version 6.x, we use Split Path, which doesn't test for file existence:

Split-Path "C:\Folder\SubFolder\myfile.txt" -Leaf

This returns "myfile.txt". If we know that the file name doesn't have periods in it, we can split the string and take the first part:

(Split-Path "C:\Folder\SubFolder\myfile.txt" -Leaf).Split('.') | Select -First 1

or

(Split-Path "C:\Folder\SubFolder\myfile.txt" -Leaf).Split('.')[0]

This returns "myfile". If the file name might include periods, to be safe, we could use the following:

$FileName = Split-Path "C:\Folder\SubFolder\myfile.txt.config.txt" -Leaf
$Extension = $FileName.Split('.') | Select -Last 1
$FileNameWoExt = $FileName.Substring(0, $FileName.Length - $Extension.Length - 1)

This returns "myfile.txt.config". Here I prefer to use Substring() instead of Replace() because the extension preceded by a period could also be part of the name, as in my example. By using Substring we return the filename without the extension as requested.

How to handle command-line arguments in PowerShell

You are reinventing the wheel. Normal PowerShell scripts have parameters starting with -, like script.ps1 -server http://devserver

Then you handle them in param section in the beginning of the file.

You can also assign default values to your params, read them from console if not available or stop script execution:

 param (
    [string]$server = "http://defaultserver",
    [Parameter(Mandatory=$true)][string]$username,
    [string]$password = $( Read-Host "Input password, please" )
 )

Inside the script you can simply

write-output $server

since all parameters become variables available in script scope.

In this example, the $server gets a default value if the script is called without it, script stops if you omit the -username parameter and asks for terminal input if -password is omitted.

Update: You might also want to pass a "flag" (a boolean true/false parameter) to a PowerShell script. For instance, your script may accept a "force" where the script runs in a more careful mode when force is not used.

The keyword for that is [switch] parameter type:

 param (
    [string]$server = "http://defaultserver",
    [string]$password = $( Read-Host "Input password, please" ),
    [switch]$force = $false
 )

Inside the script then you would work with it like this:

if ($force) {
  //deletes a file or does something "bad"
}

Now, when calling the script you'd set the switch/flag parameter like this:

.\yourscript.ps1 -server "http://otherserver" -force

If you explicitly want to state that the flag is not set, there is a special syntax for that

.\yourscript.ps1 -server "http://otherserver" -force:$false

Links to relevant Microsoft documentation (for PowerShell 5.0; tho versions 3.0 and 4.0 are also available at the links):

Running a command as Administrator using PowerShell?

You can also force the application to open as administrator, if you have an administrator account, of course.

enter image description here

Locate the file, right click > properties > Shortcut > Advanced and check Run as Administrator

Then Click OK.

How open PowerShell as administrator from the run window

The easiest way to open an admin Powershell window in Windows 10 (and Windows 8) is to add a "Windows Powershell (Admin)" option to the "Power User Menu". Once this is done, you can open an admin powershell window via Win+X,A or by right-clicking on the start button and selecting "Windows Powershell (Admin)":

[Windows 10/Windows 8 Power User menu with "Windows Powershell (Admin)

Here's where you replace the "Command Prompt" option with a "Windows Powershell" option:

[Taskbar and Start Menu Properties: "Replace Command Prompt With Windows Powershell"

Parsing xml using powershell

[xml]$xmlfile = '<xml> <Section name="BackendStatus"> <BEName BE="crust" Status="1" /> <BEName BE="pizza" Status="1" /> <BEName BE="pie" Status="1" /> <BEName BE="bread" Status="1" /> <BEName BE="Kulcha" Status="1" /> <BEName BE="kulfi" Status="1" /> <BEName BE="cheese" Status="1" /> </Section> </xml>'

foreach ($bename in $xmlfile.xml.Section.BEName) {
    if($bename.Status -eq 1){
        #Do something
    }
}

How to pass command-line arguments to a PowerShell ps1 file

Maybe you can wrap the PowerShell invocation in a .bat file like so:

rem ps.bat
@echo off
powershell.exe -command "%*"

If you then placed this file under a folder in your PATH, you could call PowerShell scripts like this:

ps foo 1 2 3

Quoting can get a little messy, though:

ps write-host """hello from cmd!""" -foregroundcolor green

Store a cmdlet's result value in a variable in Powershell

Just access the Priority property of the object returned from the pipeline:

$var = (Get-WSManInstance -enumerate wmicimv2/win32_process).Priority

(This won't work if Get-WSManInstance returns multiple objects.2)

For the second question: to get two properties there are several options, problably the simplest is to have have one variable* containing an object with two separate properties:

$var = (Get-WSManInstance -enumerate wmicimv2/win32_process | select -first 1 Priority, ProcessID)

and then use, assuming only one process:

$var.Priority

and

$var.ProcessID

If there are multiple processes $var will be an array which you can index, so to get the properties of the first process (using the array literal syntax @(...) so it is always a collection1):

$var = @(Get-WSManInstance -enumerate wmicimv2/win32_process | select -first 1 Priority, ProcessID)

and then use:

$var[0].Priority
$var[0].ProcessID

1 PowerShell helpfully for the command line, but not so helpfully in scripts has some extra logic when assigning the result of a pipeline to a variable: if no objects are returned then set $null, if one is returned then that object is assigned, otherwise an array is assigned. Forcing an array returns an array with zero, one or more (respectively) elements.

2 This changes in PowerShell V3 (at the time of writing in Release Candidate), using a member property on an array of objects will return an array of the value of those properties.

Echo equivalent in PowerShell for script testing

PowerShell interpolates, does it not?

In PHP

echo "filesizecounter: " . $filesizecounter 

can also be written as:

echo "filesizecounter: $filesizecounter" 

In PowerShell something like this should suit your needs:

Write-Host "filesizecounter: $filesizecounter"

How to tell PowerShell to wait for each command to end before starting the next?

Besides using Start-Process -Wait, piping the output of an executable will make Powershell wait. Depending on the need, I will typically pipe to Out-Null, Out-Default, Out-String or Out-String -Stream. Here is a long list of some other output options.

# Saving output as a string to a variable.
$output = ping.exe example.com | Out-String

# Filtering the output.
ping stackoverflow.com | where { $_ -match '^reply' }

# Using Start-Process affords the most control.
Start-Process -Wait SomeExecutable.com

I do miss the CMD/Bash style operators that you referenced (&, &&, ||). It seems we have to be more verbose with Powershell.

How do I assign a null value to a variable in PowerShell?

These are automatic variables, like $null, $true, $false etc.

about_Automatic_Variables, see https://technet.microsoft.com/en-us/library/hh847768.aspx?f=255&MSPPError=-2147217396

$NULL
$null is an automatic variable that contains a NULL or empty value. You can use this variable to represent an absent or undefined value in commands and scripts.

Windows PowerShell treats $null as an object with a value, that is, as an explicit placeholder, so you can use $null to represent an empty value in a series of values.

For example, when $null is included in a collection, it is counted as one of the objects.

C:\PS> $a = ".dir", $null, ".pdf"
C:\PS> $a.count
3

If you pipe the $null variable to the ForEach-Object cmdlet, it generates a value for $null, just as it does for the other objects.

PS C:\ps-test> ".dir", $null, ".pdf" | Foreach {"Hello"}
Hello
Hello
Hello

As a result, you cannot use $null to mean "no parameter value." A parameter value of $null overrides the default parameter value.

However, because Windows PowerShell treats the $null variable as a placeholder, you can use it scripts like the following one, which would not work if $null were ignored.

$calendar = @($null, $null, “Meeting”, $null, $null, “Team Lunch”, $null)
$days = Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"
$currentDay = 0

foreach($day in $calendar)
{
    if($day –ne $null)
    {
        "Appointment on $($days[$currentDay]): $day"
    }

    $currentDay++
}

output:

Appointment on Tuesday: Meeting
Appointment on Friday: Team lunch

Execute PowerShell Script from C# with Commandline Arguments

For me, the most flexible way to run PowerShell script from C# was using PowerShell.Create().AddScript()

The snippet of the code is

string scriptDirectory = Path.GetDirectoryName(
    ConfigurationManager.AppSettings["PathToTechOpsTooling"]);

var script =    
    "Set-Location " + scriptDirectory + Environment.NewLine +
    "Import-Module .\\script.psd1" + Environment.NewLine +
    "$data = Import-Csv -Path " + tempCsvFile + " -Encoding UTF8" + 
        Environment.NewLine +
    "New-Registration -server " + dbServer + " -DBName " + dbName + 
       " -Username \"" + user.Username + "\" + -Users $userData";

_powershell = PowerShell.Create().AddScript(script);
_powershell.Invoke<User>();
foreach (var errorRecord in _powershell.Streams.Error)
    Console.WriteLine(errorRecord);

You can check if there's any error by checking Streams.Error. It was really handy to check the collection. User is the type of object the PowerShell script returns.

How to create an ArrayList from an Array in PowerShell?

Probably the shortest version:

[System.Collections.ArrayList]$someArray

It is also faster because it does not call relatively expensive New-Object.

Best way to check if an PowerShell Object exist?

I would stick with the $null check since any value other than '' (empty string), 0, $false and $null will pass the check: if ($ie) {...}.

How to count objects in PowerShell?

As short as @jumbo's answer is :-) you can do it even more tersely. This just returns the Count property of the array returned by the antecedent sub-expression:

@(Get-Alias).Count

A couple points to note:

  1. You can put an arbitrarily complex expression in place of Get-Alias, for example:

    @(Get-Process | ? { $_.ProcessName -eq "svchost" }).Count
    
  2. The initial at-sign (@) is necessary for a robust solution. As long as the answer is two or greater you will get an equivalent answer with or without the @, but when the answer is zero or one you will get no output unless you have the @ sign! (It forces the Count property to exist by forcing the output to be an array.)

2012.01.30 Update

The above is true for PowerShell V2. One of the new features of PowerShell V3 is that you do have a Count property even for singletons, so the at-sign becomes unimportant for this scenario.

How to format a DateTime in PowerShell

A simple and nice way is:

$time = (Get-Date).ToString("yyyy:MM:dd")

Finding modified date of a file/folder

Here's what worked for me:

$a = Get-ChildItem \\server\XXX\Received_Orders\*.* | Where{$_.LastWriteTime -ge (Get-Date).AddDays(-7)}
if ($a = (Get-ChildItem \\server\XXX\Received_Orders\*.* | Where{$_.LastWriteTime -gt (Get-Date).AddDays(-7)}  
#Im using the -gt switch instead of -ge
{}
Else
{
'STORE XXX HAS NOT RECEIVED ANY ORDERS IN THE PAST 7 DAYS'
}


$b = Get-ChildItem \\COMP NAME\Folder\*.* | Where{$_.LastWriteTime -ge (Get-Date).AddDays(-1)}
if ($b = (Get-ChildItem \\COMP NAME\TFolder\*.* | Where{$_.LastWriteTime -gt (Get-Date).AddDays(-1)))}
{}
Else
{
'STORE XXX DID NOT RUN ITS BACKUP LAST NIGHT'
}

Output PowerShell variables to a text file

I was lead here in my Google searching. In a show of good faith I have included what I pieced together from parts of this code and other code I've gathered along the way.

_x000D_
_x000D_
# This script is useful if you have attributes or properties that span across several commandlets_x000D_
# and you wish to export a certain data set but all of the properties you wish to export are not_x000D_
# included in only one commandlet so you must use more than one to export the data set you want_x000D_
#_x000D_
# Created: Joshua Biddle 08/24/2017_x000D_
# Edited: Joshua Biddle 08/24/2017_x000D_
#_x000D_
_x000D_
$A = Get-ADGroupMember "YourGroupName"_x000D_
_x000D_
# Construct an out-array to use for data export_x000D_
$Results = @()_x000D_
_x000D_
foreach ($B in $A)_x000D_
    {_x000D_
  # Construct an object_x000D_
        $myobj = Get-ADuser $B.samAccountName -Properties ScriptPath,Office_x000D_
  _x000D_
  # Fill the object_x000D_
  $Properties = @{_x000D_
  samAccountName = $myobj.samAccountName_x000D_
  Name = $myobj.Name _x000D_
  Office = $myobj.Office _x000D_
  ScriptPath = $myobj.ScriptPath_x000D_
  }_x000D_
_x000D_
        # Add the object to the out-array_x000D_
        $Results += New-Object psobject -Property $Properties_x000D_
        _x000D_
  # Wipe the object just to be sure_x000D_
        $myobj = $null_x000D_
    }_x000D_
_x000D_
# After the loop, export the array to CSV_x000D_
$Results | Select "samAccountName", "Name", "Office", "ScriptPath" | Export-CSV "C:\Temp\YourData.csv"
_x000D_
_x000D_
_x000D_

Cheers

How do I get only directories using Get-ChildItem?

You'll want to use Get-ChildItem to recursively get all folders and files first. And then pipe that output into a Where-Object clause which only take the files.

# one of several ways to identify a file is using GetType() which
# will return "FileInfo" or "DirectoryInfo"
$files = Get-ChildItem E:\ -Recurse | Where-Object {$_.GetType().Name -eq "FileInfo"} ;

foreach ($file in $files) {
  echo $file.FullName ;
}

The response content cannot be parsed because the Internet Explorer engine is not available, or

To make it work without modifying your scripts:

I found a solution here: http://wahlnetwork.com/2015/11/17/solving-the-first-launch-configuration-error-with-powershells-invoke-webrequest-cmdlet/

The error is probably coming up because IE has not yet been launched for the first time, bringing up the window below. Launch it and get through that screen, and then the error message will not come up any more. No need to modify any scripts.

ie first launch window

Converting LastLogon to DateTime format

LastLogon is the last time that the user logged into whichever domain controller you happen to have been load balanced to at the moment that you ran the GET-ADUser cmdlet, and is not replicated across the domain. You really should use LastLogonTimestamp if you want the time the last user logged in to any domain controller in your domain.

Splitting a string into separate variables

Try this:

$Object = 'FirstPart SecondPart' | ConvertFrom-String -PropertyNames Val1, Val2
$Object.Val1
$Object.Val2

Cut off text in string after/before separator in powershell

This does work for a specific delimiter for a specific amount of characters between the delimiter. I had many issues attempting to use this in a for each loop where the position changed but the delimiter was the same. For example I was using the backslash as the delimiter and wanted to only use everything to the right of the backslash. The issue was that once the position was defined (71 characters from the beginning) it would use $pos as 71 every time regardless of where the delimiter actually was in the script. I found another method of using a delimiter and .split to break things up then used the split variable to call the sections For instance the first section was $variable[0] and the second section was $variable[1].

How to use operator '-replace' in PowerShell to replace strings of texts with special characters and replace successfully

In your example, you prepended your source string with AccountKey= but not your target string.

$c = $c -replace 'AccountKey=eKkij32jGEIYIEqAR5RjkKgf4OTiMO6SAyF68HsR/Zd/KXoKvSdjlUiiWyVV2+OUFOrVsd7jrzhldJPmfBBpQA==','AccountKey=DdOegAhDmLdsou6Ms6nPtP37bdw6EcXucuT47lf9kfClA6PjGTe3CfN+WVBJNWzqcQpWtZf10tgFhKrnN48lXA=='

By not including that in the target string, the resulting string will remove AccountKey= instead of replacing it. You correctly do this with the AccountName= example, which seems to support this conclusion since it is not giving you any problems. If you really mean to have that prepended, then this may resolve your issue.

How to get an object's property's value by property name?

Try this :

$obj = @{
    SomeProp = "Hello"
}

Write-Host "Property Value is $($obj."SomeProp")"

Powershell command to hide user from exchange address lists

You can use the following script, just replace DOMAIN with the name of your domain. When executed it will prompt you for a userlogin then hide that user's account from the address lists.

$name=Read-Host "Enter login name of user to hide"
Set-Mailbox -Identity DOMAIN\$name -HiddenFromAddressListsEnabled $true

Brian.

How to use HTTP GET in PowerShell?

In PowerShell v3, have a look at the Invoke-WebRequest and Invoke-RestMethod e.g.:

$msg = Read-Host -Prompt "Enter message"
$encmsg = [System.Web.HttpUtility]::UrlEncode($msg)
Invoke-WebRequest -Uri "http://smsserver/SNSManager/msgSend.jsp?uid&to=smartsms:*+001XXXXXX&msg=$encmsg&encoding=windows-1255"

How to pass boolean values to a PowerShell script from a command prompt

I think, best way to use/set boolean value as parameter is to use in your PS script it like this:

Param(
    [Parameter(Mandatory=$false)][ValidateSet("true", "false")][string]$deployApp="false"   
)

$deployAppBool = $false
switch($deployPmCmParse.ToLower()) {
    "true" { $deployAppBool = $true }
    default { $deployAppBool = $false }
}

So now you can use it like this:

.\myApp.ps1 -deployAppBool True
.\myApp.ps1 -deployAppBool TRUE
.\myApp.ps1 -deployAppBool true
.\myApp.ps1 -deployAppBool "true"
.\myApp.ps1 -deployAppBool false
#and etc...

So in arguments from cmd you can pass boolean value as simple string :).

How to make sure that a certain Port is not occupied by any other process

It's netstat -ano|findstr port no

Result would show process id in last column

Opening a folder in explorer and selecting a file

// suppose that we have a test.txt at E:\
string filePath = @"E:\test.txt";
if (!File.Exists(filePath))
{
    return;
}

// combine the arguments together
// it doesn't matter if there is a space after ','
string argument = "/select, \"" + filePath +"\"";

System.Diagnostics.Process.Start("explorer.exe", argument);

Saving response from Requests to file

I believe all the existing answers contain the relevant information, but I would like to summarize.

The response object that is returned by requests get and post operations contains two useful attributes:

Response attributes

  • response.text - Contains str with the response text.
  • response.content - Contains bytes with the raw response content.

You should choose one or other of these attributes depending on the type of response you expect.

  • For text-based responses (html, json, yaml, etc) you would use response.text
  • For binary-based responses (jpg, png, zip, xls, etc) you would use response.content.

Writing response to file

When writing responses to file you need to use the open function with the appropriate file write mode.

  • For text responses you need to use "w" - plain write mode.
  • For binary responses you need to use "wb" - binary write mode.

Examples

Text request and save

# Request the HTML for this web page:
response = requests.get("https://stackoverflow.com/questions/31126596/saving-response-from-requests-to-file")
with open("response.txt", "w") as f:
    f.write(response.text)

Binary request and save

# Request the profile picture of the OP:
response = requests.get("https://i.stack.imgur.com/iysmF.jpg?s=32&g=1")
with open("response.jpg", "wb") as f:
    f.write(response.content)

Answering the original question

The original code should work by using wb and response.content:

import requests

files = {'f': ('1.pdf', open('1.pdf', 'rb'))}
response = requests.post("https://pdftables.com/api?&format=xlsx-single",files=files)
response.raise_for_status() # ensure we notice bad responses
file = open("out.xls", "wb")
file.write(response.content)
file.close()

But I would go further and use the with context manager for open.

import requests

with open('1.pdf', 'rb') as file:
    files = {'f': ('1.pdf', file)}
    response = requests.post("https://pdftables.com/api?&format=xlsx-single",files=files)

response.raise_for_status() # ensure we notice bad responses

with open("out.xls", "wb") as file:
    file.write(response.content)

How to write html code inside <?php ?>, I want write html code within the PHP script so that it can be echoed from Backend

You can drop in and out of the PHP context using the <?php and ?> tags. For example...

<?php
$array = array(1, 2, 3, 4);
?>

<table>
<thead><tr><th>Number</th></tr></thead>
<tbody>
<?php foreach ($array as $num) : ?>
<tr><td><?= htmlspecialchars($num) ?></td></tr>
<?php endforeach ?>
</tbody>
</table>

Also see Alternative syntax for control structures

Best way to compare dates in Android

SimpleDateFormat sdf=new SimpleDateFormat("d/MM/yyyy");
Date date=null;
Date date1=null;
try {
       date=sdf.parse(startDate);
       date1=sdf.parse(endDate);
    }  catch (ParseException e) {
              e.printStackTrace();
    }
if (date1.after(date) && date1.equals(date)) {
//..do your work..//
}

Add data to JSONObject

The answer is to use a JSONArray as well, and to dive "deep" into the tree structure:

JSONArray arr = new JSONArray();
arr.put (...); // a new JSONObject()
arr.put (...); // a new JSONObject()

JSONObject json = new JSONObject();
json.put ("aoColumnDefs",arr);

When and where to use GetType() or typeof()?

You may find it easier to use the is keyword:

if (mycontrol is TextBox)

how to use font awesome in own css?

you can do so by using the :before or :after pseudo. read more about it here http://astronautweb.co/snippet/font-awesome/

change your code to this

.lb-prev:hover {
  filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=100);
  opacity: 1;
   text-decoration: none;
}

.lb-prev:before {
    font-family: FontAwesome;
    content: "\f053";
    font-size: 30px;
}

do the same for the other icons. you might want to adjust the color and height of the icons too. anyway here is the fiddle hope this helps

How to hide UINavigationBar 1px bottom line

Two lines solution that works for me. Try to add this in ViewDidLoad method:

navigationController?.navigationBar.setValue(true, forKey: "hidesShadow")
self.extendedLayoutIncludesOpaqueBars = true

Error: "setFile(null,false) call failed" when using log4j

Have a look at the error - 'log4j:ERROR setFile(null,false) call failed. java.io.FileNotFoundException: logs (Access is denied)'

It seems there's a log file named as 'logs' to which access is denied i.e it is not having sufficient permissions to write logs. Try by giving write permissions to the 'logs' log file. Hope it helps.

Maven fails to find local artifact

Catch all. When solutions mentioned here don't work(happend in my case), simply delete all contents from '.m2' folder/directory, and do mvn clean install.

How to pass an event object to a function in Javascript?

  1. Modify the definition of the function check_me as::

     function check_me(ev) {
    
  2. Now you can access the methods and parameters of the event, in your case:

     ev.preventDefault();
    
  3. Then, you have to pass the parameter on the onclick in the inline call::

     <button type="button" onclick="check_me(event);">Click Me!</button>
    

A useful link to understand this.


Full example:

<!DOCTYPE html>
<html lang="en">
  <head>
    <script type="text/javascript">
      function check_me(ev) {
        ev.preventDefault();
        alert("Hello World!")
      }
    </script>
  </head>
  <body>
    <button type="button" onclick="check_me(event);">Click Me!</button>
  </body>
</html>









Alternatives (best practices):

Although the above is the direct answer to the question (passing an event object to an inline event), there are other ways of handling events that keep the logic separated from the presentation

A. Using addEventListener:

<!DOCTYPE html>
<html lang="en">
  <head>
  </head>
  <body>
    <button id='my_button' type="button">Click Me!</button>

    <!-- put the javascript at the end to guarantee that the DOM is ready to use-->
    <script type="text/javascript">
      function check_me(ev) {
        ev.preventDefault();
        alert("Hello World!")
      }
      
      <!-- add the event to the button identified #my_button -->
      document.getElementById("my_button").addEventListener("click", check_me);
    </script>
  </body>
</html>

B. Isolating Javascript:

Both of the above solutions are fine for a small project, or a hackish quick and dirty solution, but for bigger projects, it is better to keep the HTML separated from the Javascript.

Just put this two files in the same folder:

  • example.html:
<!DOCTYPE html>
<html lang="en">
  <head>
  </head>
  <body>
    <button id='my_button' type="button">Click Me!</button>

    <!-- put the javascript at the end to guarantee that the DOM is ready to use-->
    <script type="text/javascript" src="example.js"></script>
  </body>
</html>
  • example.js:
function check_me(ev) {
    ev.preventDefault();
    alert("Hello World!")
}
document.getElementById("my_button").addEventListener("click", check_me);

Find running median from a stream of integers

Efficient is a word that depends on context. The solution to this problem depends on the amount of queries performed relative to the amount of insertions. Suppose you are inserting N numbers and K times towards the end you were interested in the median. The heap based algorithm's complexity would be O(N log N + K).

Consider the following alternative. Plunk the numbers in an array, and for each query, run the linear selection algorithm (using the quicksort pivot, say). Now you have an algorithm with running time O(K N).

Now if K is sufficiently small (infrequent queries), the latter algorithm is actually more efficient and vice versa.

How can I change the text inside my <span> with jQuery?

$('#abc span').html('A new text for the span.');

When to catch java.lang.Error?

Very, very rarely.

I did it only for one very very specific known cases. For example, java.lang.UnsatisfiedLinkError could be throw if two independence ClassLoader load same DLL. (I agree that I should move the JAR to a shared classloader)

But most common case is that you needed logging in order to know what happened when user come to complain. You want a message or a popup to user, rather then silently dead.

Even programmer in C/C++, they pop an error and tell something people don't understand before it exit (e.g. memory failure).

Format output string, right alignment

Try this approach using the newer str.format syntax:

line_new = '{:>12}  {:>12}  {:>12}'.format(word[0], word[1], word[2])

And here's how to do it using the old % syntax (useful for older versions of Python that don't support str.format):

line_new = '%12s  %12s  %12s' % (word[0], word[1], word[2])

How to make a HTTP PUT request?

How to use PUT method using WebRequest.

    //JsonResultModel class
    public class JsonResultModel
    {
       public string ErrorMessage { get; set; }
       public bool IsSuccess { get; set; }
       public string Results { get; set; }
    }
    // HTTP_PUT Function
    public static JsonResultModel HTTP_PUT(string Url, string Data)
    {
        JsonResultModel model = new JsonResultModel();
        string Out = String.Empty;
        string Error = String.Empty;
        System.Net.WebRequest req = System.Net.WebRequest.Create(Url);

        try
        {
            req.Method = "PUT";
            req.Timeout = 100000;
            req.ContentType = "application/json";
            byte[] sentData = Encoding.UTF8.GetBytes(Data);
            req.ContentLength = sentData.Length;

            using (System.IO.Stream sendStream = req.GetRequestStream())
            {
                sendStream.Write(sentData, 0, sentData.Length);
                sendStream.Close();

            }

            System.Net.WebResponse res = req.GetResponse();
            System.IO.Stream ReceiveStream = res.GetResponseStream();
            using (System.IO.StreamReader sr = new 
            System.IO.StreamReader(ReceiveStream, Encoding.UTF8))
            {

                Char[] read = new Char[256];
                int count = sr.Read(read, 0, 256);

                while (count > 0)
                {
                    String str = new String(read, 0, count);
                    Out += str;
                    count = sr.Read(read, 0, 256);
                }
            }
        }
        catch (ArgumentException ex)
        {
            Error = string.Format("HTTP_ERROR :: The second HttpWebRequest object has raised an Argument Exception as 'Connection' Property is set to 'Close' :: {0}", ex.Message);
        }
        catch (WebException ex)
        {
            Error = string.Format("HTTP_ERROR :: WebException raised! :: {0}", ex.Message);
        }
        catch (Exception ex)
        {
            Error = string.Format("HTTP_ERROR :: Exception raised! :: {0}", ex.Message);
        }

        model.Results = Out;
        model.ErrorMessage = Error;
        if (!string.IsNullOrWhiteSpace(Out))
        {
            model.IsSuccess = true;
        }
        return model;
    }

Get the first key name of a JavaScript object

You can query the content of an object, per its array position.
For instance:

 let obj = {plainKey: 'plain value'};

 let firstKey = Object.keys(obj)[0]; // "plainKey"
 let firstValue = Object.values(obj)[0]; // "plain value"

 /* or */

 let [key, value] = Object.entries(obj)[0]; // ["plainKey", "plain value"]

 console.log(key); // "plainKey"
 console.log(value); // "plain value"

Difference between "move" and "li" in MIPS assembly language

The move instruction copies a value from one register to another. The li instruction loads a specific numeric value into that register.

For the specific case of zero, you can use either the constant zero or the zero register to get that:

move $s0, $zero
li   $s0, 0

There's no register that generates a value other than zero, though, so you'd have to use li if you wanted some other number, like:

li $s0, 12345678

How to group time by hour or by 10 minutes

finally done with

GROUP BY
DATEPART(YEAR, DT.[Date]),
DATEPART(MONTH, DT.[Date]),
DATEPART(DAY, DT.[Date]),
DATEPART(HOUR, DT.[Date]),
(DATEPART(MINUTE, DT.[Date]) / 10)

Setting individual axis limits with facet_wrap and scales = "free" in ggplot2

Here's some code with a dummy geom_blank layer,

range_act <- range(range(results$act), range(results$pred))

d <- reshape2::melt(results, id.vars = "pred")

dummy <- data.frame(pred = range_act, value = range_act,
                    variable = "act", stringsAsFactors=FALSE)

ggplot(d, aes(x = pred, y = value)) +
  facet_wrap(~variable, scales = "free") +
  geom_point(size = 2.5) + 
  geom_blank(data=dummy) + 
  theme_bw()

enter image description here

Correct way to find max in an Array in Swift

Swift 3.0

You can try this code programmatically.

func getSmallAndGreatestNumber() -> Void {

    let numbers = [145, 206, 116, 809, 540, 176]
    var i = 0
    var largest = numbers[0]
    var small = numbers[0]
    while i < numbers.count{

        if (numbers[i] > largest) {
            largest = numbers[i]
        }
        if (numbers[i] < small) {
            small = numbers[i]
        }
        i = i + 1
    }
    print("Maximum Number ====================\(largest)")// 809
    print("Minimum Number ====================\(small)")// 116
}

How do you take a git diff file, and apply it to a local branch that is a copy of the same repository?

Copy the diff file to the root of your repository, and then do:

git apply yourcoworkers.diff

More information about the apply command is available on its man page.

By the way: A better way to exchange whole commits by file is the combination of the commands git format-patch on the sender and then git am on the receiver, because it also transfers the authorship info and the commit message.

If the patch application fails and if the commits the diff was generated from are actually in your repo, you can use the -3 option of apply that tries to merge in the changes.

It also works with Unix pipe as follows:

git diff d892531 815a3b5 | git apply

How are software license keys generated?

There are also DRM behaviors that incorporate multiple steps to the process. One of the most well known examples is one of Adobe's methods for verifying an installation of their Creative Suite. The traditional CD Key method discussed here is used, then Adobe's support line is called. The CD key is given to the Adobe representative and they give back an activation number to be used by the user.

However, despite being broken up into steps, this falls prey to the same methods of cracking used for the normal process. The process used to create an activation key that is checked against the original CD key was quickly discovered, and generators that incorporate both of the keys were made.

However, this method still exists as a way for users with no internet connection to verify the product. Going forward, it's easy to see how these methods would be eliminated as internet access becomes ubiquitous.

How to use BOOLEAN type in SELECT statement

With Oracle 12, you can use the WITH clause to declare your auxiliary functions. I'm assuming your get_something function returns varchar2:

with
  function get_something_(name varchar2, ignore_notfound number)
  return varchar2 
  is
  begin
    -- Actual function call here
    return get_something(name, not ignore_notfound = 0);
  end get_something_;

  -- Call auxiliary function instead of actual function
select get_something_('NAME', 1) from dual;

Of course, you could have also stored your auxiliary function somewhere in the schema as shown in this answer, but by using WITH, you don't have any external dependencies just to run this query. I've blogged about this technique more in detail here.

How can I determine the status of a job?

we can query the msdb in many ways to get the details.

few are

select job.Name, job.job_ID, job.Originating_Server,activity.run_requested_Date,
datediff(minute, activity.run_requested_Date, getdate()) as Elapsed 
from msdb.dbo.sysjobs_view job 
inner join msdb.dbo.sysjobactivity activity on (job.job_id = activity.job_id) 
where run_Requested_date is not null 
and stop_execution_date is null 
and job.name like 'Your Job Prefix%'

Can't access Tomcat using IP address

Check your windows-firewall feature in control panel. Outbound and inbound port should allow port 8089. (or write a new rule for this- Right hand side, actions - new rules.) it worked for me!

Converting a double to an int in Javascript without rounding

A trick to truncate that avoids a function call entirely is

var number = 2.9
var truncated = number - number % 1;
console.log(truncated); // 2 

To round a floating-point number to the nearest integer, use the addition/subtraction trick. This works for numbers with absolute value < 2 ^ 51.

var number = 2.9
var rounded = number + 6755399441055744.0 - 6755399441055744.0;  // (2^52 + 2^51)
console.log(rounded); // 3 

Note:

Halfway values are rounded to the nearest even using "round half to even" as the tie-breaking rule. Thus, for example, +23.5 becomes +24, as does +24.5. This variant of the round-to-nearest mode is also called bankers' rounding.

The magic number 6755399441055744.0 is explained in the stackoverflow post "A fast method to round a double to a 32-bit int explained".

_x000D_
_x000D_
// Round to whole integers using arithmetic operators
let trunc = (v) => v - v % 1;
let ceil  = (v) => trunc(v % 1 > 0 ? v + 1 : v);
let floor = (v) => trunc(v % 1 < 0 ? v - 1 : v);
let round = (v) => trunc(v < 0 ? v - 0.5 : v + 0.5);

let roundHalfEven = (v) => v + 6755399441055744.0 - 6755399441055744.0; // (2^52 + 2^51)

console.log("number  floor   ceil  round  trunc");
var array = [1.5, 1.4, 1.0, -1.0, -1.4, -1.5];
array.forEach(x => {
    let f = x => (x).toString().padStart(6," ");
    console.log(`${f(x)} ${f(floor(x))} ${f(ceil(x))} ${f(round(x))} ${f(trunc(x))}`);  
});
_x000D_
_x000D_
_x000D_

Keep values selected after form submission

If you are using WordPress (as is the case with the OP), you can use the selected function.

<form method="get" action="">
  <select name="name">
    <option value="a" <?php selected( isset($_POST['name']) ? $_POST['name'] : '', 'a' ); ?>>a</option>
    <option value="b" <?php selected( isset($_POST['name']) ? $_POST['name'] : '', 'b' ); ?>>b</option>
  </select>
  <select name="location">
    <option value="x" <?php selected( isset($_POST['location']) ? $_POST['location'] : '', 'x' ); ?>>x</option>
    <option value="y" <?php selected( isset($_POST['location']) ? $_POST['location'] : '', 'y' ); ?>>y</option>
  </select>
  <input type="submit" value="Submit" class="submit" />
</form>

SSL InsecurePlatform error when using Requests package

Use the somewhat hidden security feature:

pip install requests[security] or pip install pyOpenSSL ndg-httpsclient pyasn1

Both commands install following extra packages:

  • pyOpenSSL
  • cryptography
  • idna

Please note that this is not required for python-2.7.9+.

If pip install fails with errors, check whether you have required development packages for libffi, libssl and python installed in your system using distribution's package manager:

  • Debian/Ubuntu - python-dev libffi-dev libssl-dev packages.

  • Fedora - openssl-devel python-devel libffi-devel packages.

Distro list above is incomplete.

Workaround (see the original answer by @TomDotTom):

In case you cannot install some of the required development packages, there's also an option to disable that warning:

import requests.packages.urllib3
requests.packages.urllib3.disable_warnings()

If your pip itself is affected by InsecurePlatformWarning and cannot install anything from PyPI, it can be fixed with this step-by-step guide to deploy extra python packages manually.

C++ printing spaces or tabs given a user input integer

I just happened to look for something similar and came up with this:

std::cout << std::setfill(' ') << std::setw(n) << ' ';

JavaScript - Hide a Div at startup (load)

This method I've used a lot, not sure if it is a very good way but it works fine for my needs.

<html>
<head>  
    <script language="JavaScript">
    function setVisibility(id, visibility) {
    document.getElementById(id).style.display = visibility;
    }
    </script>
</head>
<body>
    <div id="HiddenStuff1" style="display:none">
    CONTENT TO HIDE 1
    </div>
    <div id="HiddenStuff2" style="display:none">
    CONTENT TO HIDE 2
    </div>
    <div id="HiddenStuff3" style="display:none">
    CONTENT TO HIDE 3
    </div>
    <input id="YOUR ID" title="HIDDEN STUFF 1" type=button name=type value='HIDDEN STUFF 1' onclick="setVisibility('HiddenStuff1', 'inline');setVisibility('HiddenStuff2', 'none');setVisibility('HiddenStuff3', 'none');";>
    <input id="YOUR ID" title="HIDDEN STUFF 2" type=button name=type value='HIDDEN STUFF 2' onclick="setVisibility('HiddenStuff1', 'none');setVisibility('HiddenStuff2', 'inline');setVisibility('HiddenStuff3', 'none');";>
    <input id="YOUR ID" title="HIDDEN STUFF 3" type=button name=type value='HIDDEN STUFF 3' onclick="setVisibility('HiddenStuff1', 'none');setVisibility('HiddenStuff2', 'none');setVisibility('HiddenStuff3', 'inline');";>
</body>
</html>

How to for each the hashmap?

I know I'm a bit late for that one, but I'll share what I did too, in case it helps someone else :

HashMap<String, HashMap> selects = new HashMap<String, HashMap>();

for(Map.Entry<String, HashMap> entry : selects.entrySet()) {
    String key = entry.getKey();
    HashMap value = entry.getValue();

    // do what you have to do here
    // In your case, another loop.
}

Fastest way to compute entropy in Python

Uniformly distributed data (high entropy):

s=range(0,256)

Shannon entropy calculation step by step:

import collections
import math

# calculate probability for each byte as number of occurrences / array length
probabilities = [n_x/len(s) for x,n_x in collections.Counter(s).items()]
# [0.00390625, 0.00390625, 0.00390625, ...]

# calculate per-character entropy fractions
e_x = [-p_x*math.log(p_x,2) for p_x in probabilities]
# [0.03125, 0.03125, 0.03125, ...]

# sum fractions to obtain Shannon entropy
entropy = sum(e_x)
>>> entropy 
8.0

One-liner (assuming import collections):

def H(s): return sum([-p_x*math.log(p_x,2) for p_x in [n_x/len(s) for x,n_x in collections.Counter(s).items()]])

A proper function:

import collections
import math

def H(s):
    probabilities = [n_x/len(s) for x,n_x in collections.Counter(s).items()]
    e_x = [-p_x*math.log(p_x,2) for p_x in probabilities]    
    return sum(e_x)

Test cases - English text taken from CyberChef entropy estimator:

>>> H(range(0,256))
8.0
>>> H(range(0,64))
6.0
>>> H(range(0,128))
7.0
>>> H([0,1])
1.0
>>> H('Standard English text usually falls somewhere between 3.5 and 5')
4.228788210509104

Is there any kind of hash code function in JavaScript?

If you want a hashCode() function like Java's in JavaScript, that is yours:

String.prototype.hashCode = function(){
    var hash = 0;
    for (var i = 0; i < this.length; i++) {
        var character = this.charCodeAt(i);
        hash = ((hash<<5)-hash)+character;
        hash = hash & hash; // Convert to 32bit integer
    }
    return hash;
}

That is the way of implementation in Java (bitwise operator).

Please note that hashCode could be positive and negative, and that's normal, see HashCode giving negative values. So, you could consider to use Math.abs() along with this function.

How to find GCD, LCM on a set of numbers

If you can use Java 8 (and actually want to) you can use lambda expressions to solve this functionally:

private static int gcd(int x, int y) {
    return (y == 0) ? x : gcd(y, x % y);
}

public static int gcd(int... numbers) {
    return Arrays.stream(numbers).reduce(0, (x, y) -> gcd(x, y));
}

public static int lcm(int... numbers) {
    return Arrays.stream(numbers).reduce(1, (x, y) -> x * (y / gcd(x, y)));
}

I oriented myself on Jeffrey Hantin's answer, but

  • calculated the gcd functionally
  • used the varargs-Syntax for an easier API (I was not sure if the overload would work correctly, but it does on my machine)
  • transformed the gcd of the numbers-Array into functional syntax, which is more compact and IMO easier to read (at least if you are used to functional programming)

This approach is probably slightly slower due to additional function calls, but that probably won't matter at all for the most use cases.

Iif equivalent in C#

C# has the ? ternary operator, like other C-style languages. However, this is not perfectly equivalent to IIf(); there are two important differences.

To explain the first difference, the false-part argument for this IIf() call causes a DivideByZeroException, even though the boolean argument is True.

IIf(true, 1, 1/0)

IIf() is just a function, and like all functions all the arguments must be evaluated before the call is made. Put another way, IIf() does not short circuit in the traditional sense. On the other hand, this ternary expression does short-circuit, and so is perfectly fine:

(true)?1:1/0;

The other difference is IIf() is not type safe. It accepts and returns arguments of type Object. The ternary operator is type safe. It uses type inference to know what types it's dealing with. Note you can fix this very easily with your own generic IIF(Of T)() implementation, but out of the box that's not the way it is.

If you really want IIf() in C#, you can have it:

object IIf(bool expression, object truePart, object falsePart) 
{return expression?truePart:falsePart;}

or a generic/type-safe implementation:

T IIf<T>(bool expression, T truePart, T falsePart) 
{return expression?truePart:falsePart;}

On the other hand, if you want the ternary operator in VB, Visual Studio 2008 and later provide a new If() operator that works like C#'s ternary operator. It uses type inference to know what it's returning, and it really is an operator rather than a function. This means there's no issues from pre-evaluating expressions, even though it has function semantics.

SSRS chart does not show all labels on Horizontal axis

(Three years late...) but I believe the answer to your second question is that SSRS essentially treats data from your datasets as unsorted; I'm not sure if it ignores any ORDER BY in the sql, or if it just assumes the data is unsorted.

To sort your groups in a particular order, you need to specify it in the report:

  • Select the chart,
  • In the Chart Data popup window (where you specify the Category Groups), right-click your Group and click Category Group Properties,
  • Click on the Sorting option to see a control to set the Sort order

For the report I just created, the default sort order on the category was alphabetic on the category group which was basically a string code. But sometimes it can be useful to sort by some other characteristic of the data; for example, my report is of Average and Maximum processing times for messages identified by some code (the category). By setting the sort order of the group to be on [MaxElapsedMs], Z->A it draws my attention to the worst-performing message-types.

A stacked bar chart with categories sorted by the value in one of the fields

This sort of presentation won't be useful for every report but it can be an excellent tool to guide readers to have a better understanding of the data; though on other occasions you might prefer a report to have the same ordering every time it runs, in which case sorting on the category label itself may be best... and I guess there are circumstances where changing the sort order could harm understanding, such as if the categories implied some sort of ordering (such as date values?)

Where is Java's Array indexOf?

int findIndex(int myElement, int[] someArray){
 int index = 0;
 for(int n: someArray){
   if(myElement == n) return index;
   else index++;
 }
}

Note: you can use this method for arrays of type int, you can also use this algorithm for other types with minor changes

How to properly import a selfsigned certificate into Java keystore that is available to all Java applications by default?

fist get the certificate from the provider
create a file ends wirth .cer and pase the certificate

copy the text file or  past   it  somewhere you can access it 
then use the cmd prompt as an admin and cd to the bin of the jdk,
the cammand that will be used is the:  keytool 

change the  password of the keystore with :

keytool  -storepasswd -keystore "path of the key store from c\ and down"

the password is : changeit 
 then you will be asked to enter the new password twice 

then type the following :

keytool -importcert -file  "C:\Program Files\Java\jdk-13.0.2\lib\security\certificateFile.cer"   -alias chooseAname -keystore  "C:\Program Files\Java\jdk-13.0.2\lib\security\cacerts"

How to let an ASMX file output JSON

To receive a pure JSON string, without it being wrapped into an XML, you have to write the JSON string directly to the HttpResponse and change the WebMethod return type to void.

    [System.Web.Script.Services.ScriptService]
    public class WebServiceClass : System.Web.Services.WebService {
        [WebMethod]
        public void WebMethodName()
        {
            HttpContext.Current.Response.Write("{property: value}");
        }
    }

CSS for grabbing cursors (drag & drop)

In case anyone else stumbles across this question, this is probably what you were looking for:

.grabbable {
    cursor: move; /* fallback if grab cursor is unsupported */
    cursor: grab;
    cursor: -moz-grab;
    cursor: -webkit-grab;
}

 /* (Optional) Apply a "closed-hand" cursor during drag operation. */
.grabbable:active {
    cursor: grabbing;
    cursor: -moz-grabbing;
    cursor: -webkit-grabbing;
}

How to plot an array in python?

if you give a 2D array to the plot function of matplotlib it will assume the columns to be lines:

If x and/or y is 2-dimensional, then the corresponding columns will be plotted.

In your case your shape is not accepted (100, 1, 1, 8000). As so you can using numpy squeeze to solve the problem quickly:

np.squeez doc: Remove single-dimensional entries from the shape of an array.

import numpy as np
import matplotlib.pyplot as plt

data = np.random.randint(3, 7, (10, 1, 1, 80))
newdata = np.squeeze(data) # Shape is now: (10, 80)
plt.plot(newdata) # plotting by columns
plt.show()

But notice that 100 sets of 80 000 points is a lot of data for matplotlib. I would recommend that you look for an alternative. The result of the code example (run in Jupyter) is:

Jupyter matplotlib plot

Sending HTTP Post request with SOAP action using org.apache.http

This is a full working example :

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost; 
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

public void callWebService(String soapAction, String soapEnvBody)  throws IOException {
    // Create a StringEntity for the SOAP XML.
    String body ="<?xml version=\"1.0\" encoding=\"UTF-8\"?><SOAP-ENV:Envelope xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:ns1=\"http://example.com/v1.0/Records\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:SOAP-ENC=\"http://schemas.xmlsoap.org/soap/encoding/\" SOAP-ENV:encodingStyle=\"http://schemas.xmlsoap.org/soap/encoding/\"><SOAP-ENV:Body>"+soapEnvBody+"</SOAP-ENV:Body></SOAP-ENV:Envelope>";
    StringEntity stringEntity = new StringEntity(body, "UTF-8");
    stringEntity.setChunked(true);

    // Request parameters and other properties.
    HttpPost httpPost = new HttpPost("http://example.com?soapservice");
    httpPost.setEntity(stringEntity);
    httpPost.addHeader("Accept", "text/xml");
    httpPost.addHeader("SOAPAction", soapAction);

    // Execute and get the response.
    HttpClient httpClient = new DefaultHttpClient();
    HttpResponse response = httpClient.execute(httpPost);
    HttpEntity entity = response.getEntity();

    String strResponse = null;
    if (entity != null) {
        strResponse = EntityUtils.toString(entity);
    }
}

Convert System.Drawing.Color to RGB and Hex Value

e.g.

 ColorTranslator.ToHtml(Color.FromArgb(Color.Tomato.ToArgb()))

This can avoid the KnownColor trick.

Using variables inside strings

This functionality is not built-in to C# 5 or below.
Update: C# 6 now supports string interpolation, see newer answers.

The recommended way to do this would be with String.Format:

string name = "Scott";
string output = String.Format("Hello {0}", name);

However, I wrote a small open-source library called SmartFormat that extends String.Format so that it can use named placeholders (via reflection). So, you could do:

string name = "Scott";
string output = Smart.Format("Hello {name}", new{name}); // Results in "Hello Scott".

Hope you like it!

pandas groupby sort within groups

You can do it in one line -

df.groupby(['job']).apply(lambda x: x.sort_values(['count'], ascending=False).head(3)
.drop('job', axis=1))

what apply() does is that it takes each group of groupby and assigns it to the x in lambda function.

extract column value based on another column pandas dataframe

Use df[df['B']==3]['A'].values if you just want item itself without the brackets

How can I add a line to a file in a shell script?

As far as I understand, you want to prepend column1, column2, column3 to your existing one, two, three.

I would use ed in place of sed, since sed write on the standard output and not in the file.

The command:

printf '0a\ncolumn1, column2, column3\n.\nw\n' | ed testfile.csv

should do the work.

perl -i is worth taking a look as well.

You must add a reference to assembly 'netstandard, Version=2.0.0.0

Might have todo with one of these:

  1. Install a newer SDK.
  2. In .csproj check for Reference Include="netstandard"
  3. Check the assembly versions in the compilation tags in the Views\Web.config and Web.config.

error: could not create '/usr/local/lib/python2.7/dist-packages/virtualenv_support': Permission denied

It's because the virtual environment viarable has not been installed.

Try this:

sudo pip install virtualenv
virtualenv --python python3 env
source env/bin/activate
pip install <Package>

or

sudo pip3 install virtualenv
virtualenv --python python3 env
source env/bin/activate
pip3 install <Package>

Change Row background color based on cell value DataTable

Callback for whenever a TR element is created for the table's body.

$('#example').dataTable( {
      "createdRow": function( row, data, dataIndex ) {
        if ( data[4] == "A" ) {
          $(row).addClass( 'important' );
        }
      }
    } );

https://datatables.net/reference/option/createdRow

error C4996: 'scanf': This function or variable may be unsafe in c programming

Another way to suppress the error: Add this line at the top in C/C++ file:

#define _CRT_SECURE_NO_WARNINGS

Matplotlib: ValueError: x and y must have same first dimension

You should make x and y numpy arrays, not lists:

x = np.array([0.46,0.59,0.68,0.99,0.39,0.31,1.09,
              0.77,0.72,0.49,0.55,0.62,0.58,0.88,0.78])
y = np.array([0.315,0.383,0.452,0.650,0.279,0.215,0.727,0.512,
              0.478,0.335,0.365,0.424,0.390,0.585,0.511])

With this change, it produces the expect plot. If they are lists, m * x will not produce the result you expect, but an empty list. Note that m is anumpy.float64 scalar, not a standard Python float.

I actually consider this a bit dubious behavior of Numpy. In normal Python, multiplying a list with an integer just repeats the list:

In [42]: 2 * [1, 2, 3]
Out[42]: [1, 2, 3, 1, 2, 3]

while multiplying a list with a float gives an error (as I think it should):

In [43]: 1.5 * [1, 2, 3]
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-43-d710bb467cdd> in <module>()
----> 1 1.5 * [1, 2, 3]
TypeError: can't multiply sequence by non-int of type 'float'

The weird thing is that multiplying a Python list with a Numpy scalar apparently works:

In [45]: np.float64(0.5) * [1, 2, 3]
Out[45]: []

In [46]: np.float64(1.5) * [1, 2, 3]
Out[46]: [1, 2, 3]

In [47]: np.float64(2.5) * [1, 2, 3]
Out[47]: [1, 2, 3, 1, 2, 3]

So it seems that the float gets truncated to an int, after which you get the standard Python behavior of repeating the list, which is quite unexpected behavior. The best thing would have been to raise an error (so that you would have spotted the problem yourself instead of having to ask your question on Stackoverflow) or to just show the expected element-wise multiplication (in which your code would have just worked). Interestingly, addition between a list and a Numpy scalar does work:

In [69]: np.float64(0.123) + [1, 2, 3]
Out[69]: array([ 1.123,  2.123,  3.123])

Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C

This is for 32 bit, we need to change the size if we consider 8 bits.

    void bitReverse(int num)
    {
        int num_reverse = 0;
        int size = (sizeof(int)*8) -1;
        int i=0,j=0;
        for(i=0,j=size;i<=size,j>=0;i++,j--)
        {
            if((num >> i)&1)
            {
                num_reverse = (num_reverse | (1<<j));
            }
        }
        printf("\n rev num = %d\n",num_reverse);
    }

Reading the input integer "num" in LSB->MSB order and storing in num_reverse in MSB->LSB order.

Changing the color of an hr element

hr {
    height: 1px;
    color: #123455;
    background-color: #123455;
    border: none;
}

Doing it this way allows you to change the height if needed. Good luck. Source: How To Style HR with CSS

default web page width - 1024px or 980px?

If it isn't I could see things heading that way.

I'm working on redoing the website for the company I work for and the designer they hired used a 960px width layout. There is also a 960px grid system that seems to be getting quite popular (http://960.gs/).

I've been out of web stuff for a few years but from what I've read catching up on things it seems 960/980 is about right. For mobile ~320px sticks in my mind, by which 960 is divisible. 960 is also evenly divisible by 2, 3, 4, 5, and 6.

Jquery Change Height based on Browser Size/Resize

Building on Chad's answer, you also want to add that function to the onload event to ensure it is resized when the page loads as well.

jQuery.event.add(window, "load", resizeFrame);
jQuery.event.add(window, "resize", resizeFrame);

function resizeFrame() 
{
    var h = $(window).height();
    var w = $(window).width();
    $("#elementToResize").css('height',(h < 768 || w < 1024) ? 500 : 400);
}

what is the difference between const_iterator and iterator?

There is no performance difference.

A const_iterator is an iterator that points to const value (like a const T* pointer); dereferencing it returns a reference to a constant value (const T&) and prevents modification of the referenced value: it enforces const-correctness.

When you have a const reference to the container, you can only get a const_iterator.

Edited: I mentionned “The const_iterator returns constant pointers” which is not accurate, thanks to Brandon for pointing it out.

Edit: For COW objects, getting a non-const iterator (or dereferencing it) will probably trigger the copy. (Some obsolete and now disallowed implementations of std::string use COW.)

How do I create a basic UIButton programmatically?

Here's one:

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self 
           action:@selector(aMethod:)
 forControlEvents:UIControlEventTouchUpInside];
[button setTitle:@"Show View" forState:UIControlStateNormal];
button.frame = CGRectMake(80.0, 210.0, 160.0, 40.0);
[view addSubview:button];

Setting background-image using jQuery CSS property

For those using an actual URL and not a variable:

$('myObject').css('background-image', 'url(../../example/url.html)');

How do I turn off Unicode in a VC++ project?

None of the above solutions worked for me. But

#include <Windows.h>

worked fine.

Error "The input device is not a TTY"

It's not exactly what you are asking, but:

The -T key would help people who are using docker-compose exec!

docker-compose -f /srv/backend_bigdata/local.yml exec -T postgres backup

How to start jenkins on different port rather than 8080 using command prompt in Windows?

On OSX edit file:

/usr/local/Cellar/jenkins-lts/2.46.1/homebrew.mxcl.jenkins-lts.plist

and edit port to you needs.

How to turn on front flash light programmatically in Android?

Complete Code for android Flashlight App

Manifest

  <?xml version="1.0" encoding="utf-8"?>
  <manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.user.flashlight"
      android:versionCode="1"
      android:versionName="1.0">

      <uses-sdk
          android:minSdkVersion="8"
          android:targetSdkVersion="17"/>

      <uses-permission android:name="android.permission.CAMERA" />
      <uses-feature android:name="android.hardware.camera"/>

      <application
          android:allowBackup="true"
          android:icon="@mipmap/ic_launcher"
          android:label="@string/app_name"
          android:theme="@style/AppTheme" >
          <activity
              android:name=".MainActivity"
              android:label="@string/app_name" >
              <intent-filter>
                  <action android:name="android.intent.action.MAIN" />

                  <category android:name="android.intent.category.LAUNCHER" />
              </intent-filter>
          </activity>
      </application>

  </manifest>

XML

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="OFF"
        android:id="@+id/button"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true"
        android:onClick="turnFlashOnOrOff" />
</RelativeLayout>

MainActivity.java

  import android.app.AlertDialog;
  import android.content.DialogInterface;
  import android.content.pm.PackageManager;
  import android.hardware.Camera;
  import android.hardware.Camera.Parameters;
  import android.support.v7.app.AppCompatActivity;
  import android.os.Bundle;
  import android.view.View;
  import android.widget.Button;

  import java.security.Policy;

  public class MainActivity extends AppCompatActivity {

      Button button;
      private Camera camera;
      private boolean isFlashOn;
      private boolean hasFlash;
      Parameters params;

      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);

          button = (Button) findViewById(R.id.button);

          hasFlash = getApplicationContext().getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);

          if(!hasFlash) {

              AlertDialog alert = new AlertDialog.Builder(MainActivity.this).create();
              alert.setTitle("Error");
              alert.setMessage("Sorry, your device doesn't support flash light!");
              alert.setButton("OK", new DialogInterface.OnClickListener() {
                  @Override
                  public void onClick(DialogInterface dialog, int which) {
                      finish();
                  }
              });
              alert.show();
              return;
          }

          getCamera();

          button.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {

                  if (isFlashOn) {
                      turnOffFlash();
                      button.setText("ON");
                  } else {
                      turnOnFlash();
                      button.setText("OFF");
                  }

              }
          });
      }

      private void getCamera() {

          if (camera == null) {
              try {
                  camera = Camera.open();
                  params = camera.getParameters();
              }catch (Exception e) {

              }
          }

      }

      private void turnOnFlash() {

          if(!isFlashOn) {
              if(camera == null || params == null) {
                  return;
              }

              params = camera.getParameters();
              params.setFlashMode(Parameters.FLASH_MODE_TORCH);
              camera.setParameters(params);
              camera.startPreview();
              isFlashOn = true;
          }

      }

      private void turnOffFlash() {

              if (isFlashOn) {
                  if (camera == null || params == null) {
                      return;
                  }

                  params = camera.getParameters();
                  params.setFlashMode(Parameters.FLASH_MODE_OFF);
                  camera.setParameters(params);
                  camera.stopPreview();
                  isFlashOn = false;
              }
      }

      @Override
      protected void onDestroy() {
          super.onDestroy();
      }

      @Override
      protected void onPause() {
          super.onPause();

          // on pause turn off the flash
          turnOffFlash();
      }

      @Override
      protected void onRestart() {
          super.onRestart();
      }

      @Override
      protected void onResume() {
          super.onResume();

          // on resume turn on the flash
          if(hasFlash)
              turnOnFlash();
      }

      @Override
      protected void onStart() {
          super.onStart();

          // on starting the app get the camera params
          getCamera();
      }

      @Override
      protected void onStop() {
          super.onStop();

          // on stop release the camera
          if (camera != null) {
              camera.release();
              camera = null;
          }
      }

  }

How to add a new row to datagridview programmatically

Like this:

var index = dgv.Rows.Add();
dgv.Rows[index].Cells["Column1"].Value = "Column1";
dgv.Rows[index].Cells["Column2"].Value = 5.6;
//....

Full Page <iframe>

This is cross-browser and fully responsive:

<iframe
  src="https://drive.google.com/file/d/0BxrMaW3xINrsR3h2cWx0OUlwRms/preview"
  style="
    position: fixed;
    top: 0px;
    bottom: 0px;
    right: 0px;
    width: 100%;
    border: none;
    margin: 0;
    padding: 0;
    overflow: hidden;
    z-index: 999999;
    height: 100%;
  ">
</iframe>

Dropdownlist width in IE

you could just try the following...

  styleClass="someStyleWidth"
  onmousedown="javascript:if(navigator.appName=='Microsoft Internet Explorer'){this.style.position='absolute';this.style.width='auto'}" 
  onblur="this.style.position='';this.style.width=''"

I tried and it works for me. Nothing else is required.

Generating a UUID in Postgres for Insert statement?

Without extensions (cheat)

SELECT uuid_in(md5(random()::text || clock_timestamp()::text)::cstring);

output>> c2d29867-3d0b-d497-9191-18a9d8ee7830

(works at least in 8.4)

  • Thanks to @Erwin Brandstetter for clock_timestamp() explanation.

If you need a valid v4 UUID

SELECT uuid_in(overlay(overlay(md5(random()::text || ':' || clock_timestamp()::text) placing '4' from 13) placing to_hex(floor(random()*(11-8+1) + 8)::int)::text from 17)::cstring);

enter image description here * Thanks to @Denis Stafichuk @Karsten and @autronix


Also, in modern Postgres, you can simply cast:

SELECT md5(random()::text || clock_timestamp()::text)::uuid

creating array without declaring the size - java

As others have said, use ArrayList. Here's how:

public class t
{
 private List<Integer> x = new ArrayList<Integer>();

 public void add(int num)
 {
   this.x.add(num);
 }
}

As you can see, your add method just calls the ArrayList's add method. This is only useful if your variable is private (which it is).

If statements for Checkboxes

I simplification for Science_Fiction's answer I think is to use the exclusive or function so you can just have:

if(checkbox1.checked ^ checkbox2.checked)
{
//do stuff
}

That is assuming you want to do the same thing for both situations.

Windows service with timer

First approach with Windows Service is not easy..

A long time ago, I wrote a C# service.

This is the logic of the Service class (tested, works fine):

namespace MyServiceApp
{
    public class MyService : ServiceBase
    {
        private System.Timers.Timer timer;

        protected override void OnStart(string[] args)
        {
            this.timer = new System.Timers.Timer(30000D);  // 30000 milliseconds = 30 seconds
            this.timer.AutoReset = true;
            this.timer.Elapsed += new System.Timers.ElapsedEventHandler(this.timer_Elapsed);
            this.timer.Start();
        }

        protected override void OnStop()
        {
            this.timer.Stop();
            this.timer = null;
        }

        private void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
            MyServiceApp.ServiceWork.Main(); // my separate static method for do work
        }

        public MyService()
        {
            this.ServiceName = "MyService";
        }

        // service entry point
        static void Main()
        {
            System.ServiceProcess.ServiceBase.Run(new MyService());
        }
    }
}

I recommend you write your real service work in a separate static method (why not, in a console application...just add reference to it), to simplify debugging and clean service code.

Make sure the interval is enough, and write in log ONLY in OnStart and OnStop overrides.

Hope this helps!

Rails: Can't verify CSRF token authenticity when making a POST request

If you only want to skip CSRF protection for one or more controller actions (instead of the entire controller), try this

skip_before_action :verify_authenticity_token, only [:webhook, :index, :create]

Where [:webhook, :index, :create] will skip the check for those 3 actions, but you can change to whichever you want to skip

How to filter files when using scp to copy dir recursively?

There is no feature in scp to filter files. For "advanced" stuff like this, I recommend using rsync:

rsync -av --exclude '*.svn' user@server:/my/dir .

(this line copy rsync from distant folder to current one)

Recent versions of rsync tunnel over an ssh connection automatically by default.

Finding length of char array

If you are expecting 4 as output then try this:

char a[]={0x00,0xdc,0x01,0x04};

C++ - Assigning null to a std::string

I won't argue that it's a good idea (or the semantics of using nullptr with things that aren't pointers), but it's relatively simple to create a class which would provide "nullable" semantics (see nullable_string).

However, this is a much better fit for C++17's std::optional:

#include <string>
#include <iostream>
#include <optional>

// optional can be used as the return type of a factory that may fail
std::optional<std::string> create(bool b)
{
    if (b)
        return "Godzilla";
    else
        return {};
}

int main()
{
    std::cout << "create(false) returned "
              << create(false).value_or("empty") << std::endl;

    // optional-returning factory functions are usable as conditions of while and if
    if (auto str = create(true))
    {
        std::cout << "create(true) returned " << *str << std::endl;
    }
}

std::optional, as shown in the example, is convertible to bool, or you may use the has_value() method, has exceptions for bad access, etc. This provides you with nullable semantics, which seems to be what Maria was trying to accomplish.

And if you don't want to wait around for C++17 compatibility, see this answer about Boost.Optional.

CFNetwork SSLHandshake failed iOS 9

After two days of attempts and failures, what worked for me is this code of womble

with One change, according to this post we should stop using sub-keys associated with the NSExceptionDomains dictionary of that kind of Convention

  NSTemporaryExceptionMinimumTLSVersion

And use at the new Convention

  NSExceptionMinimumTLSVersion

instead.

apple documentation

my code

<key>NSAppTransportSecurity</key>
    <dict>
        <key>NSExceptionDomains</key>
        <dict>
            <key>YOUR_HOST.COM</key>
            <dict>
                <key>NSExceptionAllowsInsecureHTTPLoads</key>
                <true/>
                <key>NSExceptionMinimumTLSVersion</key>
                <string>TLSv1.0</string>
                <key>NSExceptionRequiresForwardSecrecy</key>
                <false/>
                <key>NSIncludesSubdomains</key>
                <true/>
            </dict>
        </dict>
    </dict>

Is there a cross-browser onload event when clicking the back button?

I ran into a problem that my js was not executing when the user had clicked back or forward. I first set out to stop the browser from caching, but this didn't seem to be the problem. My javascript was set to execute after all of the libraries etc. were loaded. I checked these with the readyStateChange event.

After some testing I found out that the readyState of an element in a page where back has been clicked is not 'loaded' but 'complete'. Adding || element.readyState == 'complete' to my conditional statement solved my problems.

Just thought I'd share my findings, hopefully they will help someone else.

Edit for completeness

My code looked as follows:

script.onreadystatechange(function(){ 
   if(script.readyState == 'loaded' || script.readyState == 'complete') {
      // call code to execute here.
   } 
});

In the code sample above the script variable was a newly created script element which had been added to the DOM.

Vuejs: Event on route change

Another solution for typescript user:

import Vue from "vue";
import Component from "vue-class-component";

@Component({
  beforeRouteLeave(to, from, next) {
    // incase if you want to access `this`
    // const self = this as any;
    next();
  }
})

export default class ComponentName extends Vue {}

How to format current time using a yyyyMMddHHmmss format?

import("time")

layout := "2006-01-02T15:04:05.000Z"
str := "2014-11-12T11:45:26.371Z"
t, err := time.Parse(layout, str)
if err != nil {
    fmt.Println(err)
}
fmt.Println(t)

gives:

>> 2014-11-12 11:45:26.371 +0000 UTC

Append a Lists Contents to another List C#

GlobalStrings.AddRange(localStrings);

That works.

Documentation: List<T>.AddRange(IEnumerable<T>).

Inner join with count() on three tables

As Frank pointed out, you need to use DISTINCT. Also, since you are using composite primary keys (which is perfectly fine, BTW) you need to make sure that you use the whole key in your joins:

SELECT
    P.pe_name,
    COUNT(DISTINCT O.ord_id) AS num_orders,
    COUNT(I.item_id) AS num_items
FROM
    People P
INNER JOIN Orders O ON
    O.pe_id = P.pe_id
INNER JOIN Items I ON
    I.ord_id = O.ord_id AND
    I.pe_id = O.pe_id
GROUP BY
    P.pe_name

Without I.ord_id = O.ord_id it was joining each item row to every order row for a person.

How to fix request failed on channel 0

I also faced the same issue. Just restarting my servers solved the issue.

TypeError: 'function' object is not subscriptable - Python

You can use this:

bankHoliday= [1, 0, 1, 1, 2, 0, 0, 1, 0, 0, 0, 2] #gives the list of bank holidays in each month

def bank_holiday(month):
   month -= 1#Takes away the numbers from the months, as months start at 1 (January) not at 0. There is no 0 month.
   print(bankHoliday[month])

bank_holiday(int(input("Which month would you like to check out: ")))

How to get distinct results in hibernate with joins and row-based limiting (paging)?

A slight improvement building on FishBoy's suggestion.

It is possible to do this kind of query in one hit, rather than in two separate stages. i.e. the single query below will page distinct results correctly, and also return entities instead of just IDs.

Simply use a DetachedCriteria with an id projection as a subquery, and then add paging values on the main Criteria object.

It will look something like this:

DetachedCriteria idsOnlyCriteria = DetachedCriteria.forClass(MyClass.class);
//add other joins and query params here
idsOnlyCriteria.setProjection(Projections.distinct(Projections.id()));

Criteria criteria = getSession().createCriteria(myClass);
criteria.add(Subqueries.propertyIn("id", idsOnlyCriteria));
criteria.setFirstResult(0).setMaxResults(50);
return criteria.list();

How to convert an Stream into a byte[] in C#?

"bigEnough" array is a bit of a stretch. Sure, buffer needs to be "big ebough" but proper design of an application should include transactions and delimiters. In this configuration each transaction would have a preset length thus your array would anticipate certain number of bytes and insert it into correctly sized buffer. Delimiters would ensure transaction integrity and would be supplied within each transaction. To make your application even better, you could use 2 channels (2 sockets). One would communicate fixed length control message transactions that would include information about size and sequence number of data transaction to be transferred using data channel. Receiver would acknowledge buffer creation and only then data would be sent. If you have no control over stream sender than you need multidimensional array as a buffer. Component arrays would be small enough to be manageable and big enough to be practical based on your estimate of expected data. Process logic would seek known start delimiters and then ending delimiter in subsequent element arrays. Once ending delimiter is found, new buffer would be created to store relevant data between delimiters and initial buffer would have to be restructured to allow data disposal.

As far as a code to convert stream into byte array is one below.

Stream s = yourStream;
int streamEnd = Convert.ToInt32(s.Length);
byte[] buffer = new byte[streamEnd];
s.Read(buffer, 0, streamEnd);

How to revert multiple git commits?

Similar to Jakub's answer, this allows you to easily select consecutive commits to revert.

# revert all commits from B to HEAD, inclusively
$ git revert --no-commit B..HEAD  
$ git commit -m 'message'

Get JSON object from URL

Our solution, adding some validations to response so we are sure we have a well formed json object in $json variable

$ch = curl_init();
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_URL, $url);
$result = curl_exec($ch);
curl_close($ch);
if (! $result) {
    return false;
}

$json = json_decode(utf8_encode($result));
if (empty($json) || json_last_error() !== JSON_ERROR_NONE) {
    return false;
}

Read JSON data in a shell script

There is jq for parsing json on the command line:

 jq '.Body'

Visit this for jq: https://stedolan.github.io/jq/

Using GZIP compression with Spring Boot/MVC/JavaConfig with RESTful

Enabeling GZip in Tomcat doesn't worked in my Spring Boot Project. I used CompressingFilter found here.

@Bean
public Filter compressingFilter() {
    CompressingFilter compressingFilter = new CompressingFilter();
    return compressingFilter;
}

How to resolve Value cannot be null. Parameter name: source in linq?

Error message clearly says that source parameter is null. Source is the enumerable you are enumerating. In your case it is ListMetadataKor object. And its definitely null at the time you are filtering it second time. Make sure you never assign null to this list. Just check all references to this list in your code and look for assignments.

OpenSSL Verify return code: 20 (unable to get local issuer certificate)

Is your server configured for client authentication? If so you need to pass the client certificate while connecting with the server.

element with the max height from a set of elements

_x000D_
_x000D_
ul, li {_x000D_
  list-style: none;_x000D_
  margin: 0;_x000D_
  padding: 0;_x000D_
}_x000D_
_x000D_
ul {_x000D_
  display: flex;_x000D_
  flex-wrap: wrap;_x000D_
}_x000D_
_x000D_
ul li {_x000D_
  width: calc(100% / 3);_x000D_
}_x000D_
_x000D_
img {_x000D_
  width: 100%;_x000D_
  height: auto;_x000D_
}
_x000D_
<ul>_x000D_
  <li>_x000D_
    <img src="http://img2.vetton.ru//upl/1000/346/138/vetton_ru_sddu7-2560x1600.jpg" alt="">_x000D_
    <br> Line 1_x000D_
    <br> Line 2_x000D_
  </li>_x000D_
  <li>_x000D_
    <img src="http://img2.vetton.ru//upl/1000/346/138/vetton_ru_mixwall66-2560x1600.jpg" alt="">_x000D_
    <br> Line 1_x000D_
    <br> Line 2_x000D_
    <br> Line 3_x000D_
    <br> Line 4_x000D_
  </li>_x000D_
  <li>_x000D_
    <img src="http://img2.vetton.ru//upl/1000/346/138/vetton_ru_sddu7-2560x1600.jpg" alt="">_x000D_
    <br> Line 1_x000D_
  </li>_x000D_
  <li>_x000D_
    <img src="http://img2.vetton.ru//upl/1000/346/138/vetton_ru_mixwall66-2560x1600.jpg" alt="">_x000D_
    <br> Line 1_x000D_
    <br> Line 2_x000D_
  </li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

How do I delete multiple rows with different IDs?

Disclaim: the following suggestion could be an overhead depending on the situation. The function is only tested with MSSQL 2008 R2 but seams be compatible to other versions

if you wane do this with many Id's you may could use a function which creates a temp table where you will be able to DELETE FROM the selection

how the query could look like:

-- not tested
-- @ids will contain a varchar with your ids e.g.'9 12 27 37'
DELETE FROM table WHERE id IN (SELECT i.number FROM iter_intlist_to_tbl(@ids))

here is the function:

ALTER FUNCTION iter_intlist_to_tbl (@list nvarchar(MAX))
   RETURNS @tbl TABLE (listpos int IDENTITY(1, 1) NOT NULL,
                       number  int NOT NULL) AS

   -- funktion gefunden auf http://www.sommarskog.se/arrays-in-sql-2005.html
   -- dient zum übergeben einer liste von elementen

BEGIN
    -- Deklaration der Variablen
    DECLARE @startpos int,
            @endpos   int,
            @textpos  int,
            @chunklen smallint,
            @str      nvarchar(4000),
            @tmpstr   nvarchar(4000),
            @leftover nvarchar(4000)

    -- Startwerte festlegen
   SET @textpos = 1
   SET @leftover = ''

   -- Loop 1
    WHILE @textpos <= datalength(@list) / 2
    BEGIN

        --
        SET @chunklen = 4000 - datalength(@leftover) / 2 --datalength() gibt die anzahl der bytes zurück (mit Leerzeichen)

        --
        SET @tmpstr = ltrim(@leftover + substring(@list, @textpos, @chunklen))--SUBSTRING ( @string ,start , length ) | ltrim(@string) abschneiden aller Leerzeichen am Begin des Strings

        --hochzählen der TestPosition
        SET @textpos = @textpos + @chunklen

        --start position 0 setzen
        SET @startpos = 0

        -- end position bekommt den charindex wo ein [LEERZEICHEN] gefunden wird
        SET @endpos = charindex(' ' COLLATE Slovenian_BIN2, @tmpstr)--charindex(searchChar,Wo,Startposition)

        -- Loop 2
        WHILE @endpos > 0
        BEGIN
            --str ist der string welcher zwischen den [LEERZEICHEN] steht
            SET @str = substring(@tmpstr, @startpos + 1, @endpos - @startpos - 1) 

            --wenn @str nicht leer ist wird er zu int Convertiert und @tbl unter der Spalte 'number' hinzugefügt
            IF @str <> ''
                INSERT @tbl (number) VALUES(convert(int, @str))-- convert(Ziel-Type,Value)

            -- start wird auf das letzte bekannte end gesetzt
            SET @startpos = @endpos

            -- end position bekommt den charindex wo ein [LEERZEICHEN] gefunden wird
            SET @endpos = charindex(' ' COLLATE Slovenian_BIN2, @tmpstr, @startpos + 1)
        END
        -- Loop 2

        -- dient dafür den letzten teil des strings zu selektieren
        SET @leftover = right(@tmpstr, datalength(@tmpstr) / 2 - @startpos)--right(@string,anzahl der Zeichen) bsp.: right("abcdef",3) => "def"
    END
    -- Loop 1

    --wenn @leftover nach dem entfernen aller [LEERZEICHEN] nicht leer ist wird er zu int Convertiert und @tbl unter der Spalte 'number' hinzugefügt
    IF ltrim(rtrim(@leftover)) <> ''
        INSERT @tbl (number) VALUES(convert(int, @leftover))

    RETURN
END


    -- ############################ WICHTIG ############################
    -- das is ein Beispiel wie man die Funktion benutzt
    --
    --CREATE    PROCEDURE get_product_names_iter 
    --      @ids varchar(50) AS
    --SELECT    P.ProductName, P.ProductID
    --FROM      Northwind.Products P
    --JOIN      iter_intlist_to_tbl(@ids) i ON P.ProductID = i.number
    --go
    --EXEC get_product_names_iter '9 12 27 37'
    --
    -- Funktion gefunden auf http://www.sommarskog.se/arrays-in-sql-2005.html
    -- dient zum übergeben einer Liste von Id's
    -- ############################ WICHTIG ############################

What is an idiomatic way of representing enums in Go?

You can make it so:

type MessageType int32

const (
    TEXT   MessageType = 0
    BINARY MessageType = 1
)

With this code compiler should check type of enum

How can strings be concatenated?

More efficient ways of concatenating strings are:

join():

Very efficent, but a bit hard to read.

>>> Section = 'C_type'  
>>> new_str = ''.join(['Sec_', Section]) # inserting a list of strings 
>>> print new_str 
>>> 'Sec_C_type'

String formatting:

Easy to read and in most cases faster than '+' concatenating

>>> Section = 'C_type'
>>> print 'Sec_%s' % Section
>>> 'Sec_C_type'

SEVERE: Unable to create initial connections of pool - tomcat 7 with context.xml file

I have also dealt with this exception after a fully working context.xml setup was adjusted. I didn't want environment details in the context.xml, so I took them out and saw this error. I realized I must fully create this datasource resource in code based on System Property JVM -D args.

Original error with just user/pwd/host removed: org.apache.tomcat.jdbc.pool.ConnectionPool init SEVERE: Unable to create initial connections of pool.

Removed entire contents of context.xml and try this: Initialize on startup of app server the datasource object sometime before using first connection. If using Spring this is good to do in an @Configuration bean in @Bean Datasource constructor.

package to use: org.apache.tomcat.jdbc.pool.*

PoolProperties p = new PoolProperties();
p.setUrl(jdbcUrl);
            p.setDriverClassName(driverClass);
            p.setUsername(user);
            p.setPassword(pwd);
            p.setJmxEnabled(true);
            p.setTestWhileIdle(false);
            p.setTestOnBorrow(true);
            p.setValidationQuery("SELECT 1");
            p.setTestOnReturn(false);
            p.setValidationInterval(30000);
            p.setValidationQueryTimeout(100);
            p.setTimeBetweenEvictionRunsMillis(30000);
            p.setMaxActive(100);
            p.setInitialSize(5);
            p.setMaxWait(10000);
            p.setRemoveAbandonedTimeout(60);
            p.setMinEvictableIdleTimeMillis(30000);
            p.setMinIdle(5);
            p.setLogAbandoned(true);
            p.setRemoveAbandoned(true);
            p.setJdbcInterceptors(
              "org.apache.tomcat.jdbc.pool.interceptor.ConnectionState;"+
              "org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer");
            org.apache.tomcat.jdbc.pool.DataSource ds = new org.apache.tomcat.jdbc.pool.DataSource();
            ds.setPoolProperties(p);
            return ds;

java.util.regex - importance of Pattern.compile()?

Pattern class is the entry point of the regex engine.You can use it through Pattern.matches() and Pattern.comiple(). #Difference between these two. matches()- for quickly check if a text (String) matches a given regular expression comiple()- create the reference of Pattern. So can use multiple times to match the regular expression against multiple texts.

For reference:

public static void main(String[] args) {
     //single time uses
     String text="The Moon is far away from the Earth";
     String pattern = ".*is.*";
     boolean matches=Pattern.matches(pattern,text);
     System.out.println("Matches::"+matches);

    //multiple time uses
     Pattern p= Pattern.compile("ab");
     Matcher  m=p.matcher("abaaaba");
     while(m.find()) {
         System.out.println(m.start()+ " ");
     }
}

pandas: multiple conditions while indexing data frame - unexpected behavior

You can also use query(), i.e.:

df_filtered = df.query('a == 4 & b != 2')

Getting "project" nuget configuration is invalid error

NOTE: This is mentioned in the question but restarting Visual Studio fixes the issue in most cases.

Updating Visual Studio to 'Update 2' got it working again.

Tools -> Extensions and Updates ->Visual Studio Update 2

As mentioned in the question and the link i posted therein, I'd already updated NuGet Package Manager to 3.4.4 prior to this and restarted to no avail, so I don't know if the combination of both these actions worked.

Why is access to the path denied?

I have also faced this issue when my window service started throwing the exception

System.UnauthorizedAccessException: Access to the path "C:\\Order\\Media
44aa4857-3bac-4a18-a307-820450361662.mp4" is denied.

So as a solution, I checked the user account associated with my service, as shown in below screen capture

enter image description here

So in my case it was NETWORK SERVICE

And then went to the folder properties to check if the associated user account also exists under their permission tab. It was missing in my case and when I added it and it fixed my issue.

For more information please check the below screen capture

enter image description here

Javascript array search and remove string?

use:

array.splice(2, 1);

This removes one item from the array, starting at index 2 (3rd item)

docker-compose up for only certain containers

One good solution is to run only desired services like this:

docker-compose up --build $(<services.txt)

and services.txt file look like this:

services1 services2, etc

of course if dependancy (depends_on), need to run related services together.

--build is optional, just for example.

Handling the null value from a resultset in JAVA

The code should be like given below

String selectSQL = "SELECT IFNULL(tbl.column, \"\") AS column FROM MySQL_table AS tbl";
Statement st = ...;
Result set rs = st.executeQuery(selectSQL);

Python, creating objects

class Student(object):
    name = ""
    age = 0
    major = ""

    # The class "constructor" - It's actually an initializer 
    def __init__(self, name, age, major):
        self.name = name
        self.age = age
        self.major = major

def make_student(name, age, major):
    student = Student(name, age, major)
    return student

Note that even though one of the principles in Python's philosophy is "there should be one—and preferably only one—obvious way to do it", there are still multiple ways to do this. You can also use the two following snippets of code to take advantage of Python's dynamic capabilities:

class Student(object):
    name = ""
    age = 0
    major = ""

def make_student(name, age, major):
    student = Student()
    student.name = name
    student.age = age
    student.major = major
    # Note: I didn't need to create a variable in the class definition before doing this.
    student.gpa = float(4.0)
    return student

I prefer the former, but there are instances where the latter can be useful – one being when working with document databases like MongoDB.

javascript return true or return false when and how to use it?

Your code makes no sense, maybe because it's out of context.

If you mean code like this:

$('a').click(function () {
    callFunction();
    return false;
});

The return false will return false to the click-event. That tells the browser to stop following events, like follow a link. It has nothing to do with the previous function call. Javascript runs from top to bottom more or less, so a line cannot affect a previous line.

Java - Find shortest path between 2 points in a distance weighted map

You can see a complete example using java 8, recursion and streams -> Dijkstra algorithm with java

PYTHONPATH on Linux

  1. PYTHONPATH is an environment variable
  2. Yes (see https://unix.stackexchange.com/questions/24802/on-which-unix-distributions-is-python-installed-as-part-of-the-default-install)
  3. /usr/lib/python2.7 on Ubuntu
  4. you shouldn't install packages manually. Instead, use pip. When a package isn't in pip, it usually has a setuptools setup script which will install the package into the proper location (see point 3).
  5. if you use pip or setuptools, then you don't need to set PYTHONPATH explicitly

If you look at the instructions for pyopengl, you'll see that they are consistent with points 4 and 5.

How to execute a * .PY file from a * .IPYNB file on the Jupyter notebook?

In the %run magic documentation you can find:

-i run the file in IPython’s namespace instead of an empty one. This is useful if you are experimenting with code written in a text editor which depends on variables defined interactively.

Therefore, supplying -i does the trick:

%run -i 'script.py'

The "correct" way to do it

Maybe the command above is just what you need, but with all the attention this question gets, I decided to add a few more cents to it for those who don't know how a more pythonic way would look like.
The solution above is a little hacky, and makes the code in the other file confusing (Where does this x variable come from? and what is the f function?).

I'd like to show you how to do it without actually having to execute the other file over and over again.
Just turn it into a module with its own functions and classes and then import it from your Jupyter notebook or console. This also has the advantage of making it easily reusable and jupyters contextassistant can help you with autocompletion or show you the docstring if you wrote one.
If you're constantly editing the other file, then autoreload comes to your help.

Your example would look like this:
script.py

import matplotlib.pyplot as plt

def myplot(f, x):
    """
    :param f: function to plot
    :type f: callable
    :param x: values for x
    :type x: list or ndarray

    Plots the function f(x).
    """
    # yes, you can pass functions around as if
    # they were ordinary variables (they are)
    plt.plot(x, f(x))
    plt.xlabel("Eje $x$",fontsize=16)
    plt.ylabel("$f(x)$",fontsize=16)
    plt.title("Funcion $f(x)$")

Jupyter console

In [1]: import numpy as np

In [2]: %load_ext autoreload

In [3]: %autoreload 1

In [4]: %aimport script

In [5]: def f(x):
      :     return np.exp(-x ** 2)
      :
      :

In [6]: x = np.linspace(-1, 3, 100)

In [7]: script.myplot(f, x)

In [8]: ?script.myplot
Signature: script.myplot(f, x)
Docstring:
:param f: function to plot
:type f: callable
:param x: x values
:type x: list or ndarray
File:      [...]\script.py
Type:      function

How to create an array containing 1...N

In ES6 using Array from() and keys() methods.

Array.from(Array(10).keys())
//=> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Shorter version using spread operator.

[...Array(10).keys()]
//=> [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Start from 1 by passing map function to Array from(), with an object with a length property:

Array.from({length: 10}, (_, i) => i + 1)
//=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Converting datetime.date to UTC timestamp in Python

the question is a little confused. timestamps are not UTC - they're a Unix thing. the date might be UTC? assuming it is, and if you're using Python 3.2+, simple-date makes this trivial:

>>> SimpleDate(date(2011,1,1), tz='utc').timestamp
1293840000.0

if you actually have the year, month and day you don't need to create the date:

>>> SimpleDate(2011,1,1, tz='utc').timestamp
1293840000.0

and if the date is in some other timezone (this matters because we're assuming midnight without an associated time):

>>> SimpleDate(date(2011,1,1), tz='America/New_York').timestamp
1293858000.0

[the idea behind simple-date is to collect all python's date and time stuff in one consistent class, so you can do any conversion. so, for example, it will also go the other way:

>>> SimpleDate(1293858000, tz='utc').date
datetime.date(2011, 1, 1)

]

How do I format currencies in a Vue component?

The comment by @RoyJ has a great suggestion. In the template you can just use built-in localized strings:

<small>
     Total: <b>{{ item.total.toLocaleString() }}</b>
</small>

It's not supported in some of the older browsers, but if you're targeting IE 11 and later, you should be fine.

Python speed testing - Time Difference - milliseconds

I know this is late, but I actually really like using:

import time
start = time.time()

##### your timed code here ... #####

print "Process time: " + (time.time() - start)

time.time() gives you seconds since the epoch. Because this is a standardized time in seconds, you can simply subtract the start time from the end time to get the process time (in seconds). time.clock() is good for benchmarking, but I have found it kind of useless if you want to know how long your process took. For example, it's much more intuitive to say "my process takes 10 seconds" than it is to say "my process takes 10 processor clock units"

>>> start = time.time(); sum([each**8.3 for each in range(1,100000)]) ; print (time.time() - start)
3.4001404476250935e+45
0.0637760162354
>>> start = time.clock(); sum([each**8.3 for each in range(1,100000)]) ; print (time.clock() - start)
3.4001404476250935e+45
0.05

In the first example above, you are shown a time of 0.05 for time.clock() vs 0.06377 for time.time()

>>> start = time.clock(); time.sleep(1) ; print "process time: " + (time.clock() - start)
process time: 0.0
>>> start = time.time(); time.sleep(1) ; print "process time: " + (time.time() - start)
process time: 1.00111794472

In the second example, somehow the processor time shows "0" even though the process slept for a second. time.time() correctly shows a little more than 1 second.

How to plot a very simple bar chart (Python, Matplotlib) using input *.txt file?

This code will do what you're looking for. It's based on examples found here and here.

The autofmt_xdate() call is particularly useful for making the x-axis labels readable.

import numpy as np
from matplotlib import pyplot as plt

fig = plt.figure()

width = .35
ind = np.arange(len(OY))
plt.bar(ind, OY, width=width)
plt.xticks(ind + width / 2, OX)

fig.autofmt_xdate()

plt.savefig("figure.pdf")

enter image description here

Disable webkit's spin buttons on input type="number"?

I discovered that there is a second portion of the answer to this.

The first portion helped me, but I still had a space to the right of my type=number input. I had zeroed out the margin on the input, but apparently I had to zero out the margin on the spinner as well.

This fixed it:

input[type=number]::-webkit-inner-spin-button,
input[type=number]::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

Animate background image change with jQuery

building on XGreen's approach above, with a few tweaks you can have an animated looping background. See here for example:

http://jsfiddle.net/srd76/36/

$(document).ready(function(){

var images = Array("http://placekitten.com/500/200",
               "http://placekitten.com/499/200",
               "http://placekitten.com/501/200",
               "http://placekitten.com/500/199");
var currimg = 0;


function loadimg(){

   $('#background').animate({ opacity: 1 }, 500,function(){

        //finished animating, minifade out and fade new back in           
        $('#background').animate({ opacity: 0.7 }, 100,function(){

            currimg++;

            if(currimg > images.length-1){

                currimg=0;

            }

            var newimage = images[currimg];

            //swap out bg src                
            $('#background').css("background-image", "url("+newimage+")"); 

            //animate fully back in
            $('#background').animate({ opacity: 1 }, 400,function(){

                //set timer for next
                setTimeout(loadimg,5000);

            });

        });

    });

  }
  setTimeout(loadimg,5000);

});

No Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator

Encountered the same error in below Usecase.

I tried to hit the Rest(Put mapping) end point using sprint boot(2.0.0 Snapshot Version) without having default constructor in respective bean.

But with latest Spring Boot versions(2.4.1 Version) the same piece of code is working without error.

so the bean default constructor is no longer needed in latest version of Spring Boot

Capture key press without placing an input element on the page?

For non-printable keys such as arrow keys and shortcut keys such as Ctrl-z, Ctrl-x, Ctrl-c that may trigger some action in the browser (for instance, inside editable documents or elements), you may not get a keypress event in all browsers. For this reason you have to use keydown instead, if you're interested in suppressing the browser's default action. If not, keyup will do just as well.

Attaching a keydown event to document works in all the major browsers:

document.onkeydown = function(evt) {
    evt = evt || window.event;
    if (evt.ctrlKey && evt.keyCode == 90) {
        alert("Ctrl-Z");
    }
};

For a complete reference, I strongly recommend Jan Wolter's article on JavaScript key handling.

I need to get all the cookies from the browser

Since the title didn't specify that it has to be programmatic I'll assume that it was a genuine debugging/privacy management issue and solution is browser dependent and requires a browser with built in detailed cookie management toll and/or a debugging module or a plug-in/extension. I'm going to list one and ask other people to write up on browsers they know in detail and please be precise with versions.

Chromium, Iron build (SRWare Iron 4.0.280)

The wrench(tool) menu: Options / Under The Hood / [Show cookies and website permissions] For related domains/sites type the suffix into the search box (like .foo.tv). Caveat: when you have a node (site or cookie) click-highlighted only use [Remove] to kill specific subtrees. Using [Remove All] will still delete cookies for all sites selected by search and waste your debugging session.

How to fill OpenCV image with one solid color?

For an 8-bit (CV_8U) OpenCV image, the syntax is:

Mat img(Mat(nHeight, nWidth, CV_8U);
img = cv::Scalar(50);    // or the desired uint8_t value from 0-255

How to have EditText with border in Android Lollipop

A quick and dirty solution I have used is to place the EditText inside of a FrameLayout. The margins of the EditText control the thickness of the border and the border color is determined by the background color of the FrameLayout.

Example:

<FrameLayout
    android:id="@+id/frameLayout"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="#000000">

    <EditText
        android:id="@+id/editText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="3dp"
        android:background="@android:color/white"
        android:ems="10"
        android:inputType="text"
        android:textSize="24sp" />
</FrameLayout>

But I would recommend, and the vast majority of the time I do, drawables for borders. Elite's answer is what I would go for in that case.

"Automatic" vs "Automatic (Delayed start)"

In short, services set to Automatic will start during the boot process, while services set to start as Delayed will start shortly after boot.

Starting your service Delayed improves the boot performance of your server and has security benefits which are outlined in the article Adriano linked to in the comments.

Update: "shortly after boot" is actually 2 minutes after the last "automatic" service has started, by default. This can be configured by a registry key, according to Windows Internals and other sources (3,4).

The registry keys of interest (At least in some versions of windows) are:

  • HKLM\SYSTEM\CurrentControlSet\services\<service name>\DelayedAutostart will have the value 1 if delayed, 0 if not.
  • HKLM\SYSTEM\CurrentControlSet\services\AutoStartDelay or HKLM\SYSTEM\CurrentControlSet\Control\AutoStartDelay (on Windows 10): decimal number of seconds to wait, may need to create this one. Applies globally to all Delayed services.

How to convert Varchar to Int in sql server 2008?

That is the correct way to convert it to an INT as long as you don't have any alpha characters or NULL values.

If you have any NULL values, use

ISNULL(column1, 0)

How to split the screen with two equal LinearLayouts?

In order to split the ui into two equal parts you can use weightSum of 2 in the parent LinearLayout and assign layout_weight of 1 to each as shown below

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal"
    android:weightSum="2">

        <LinearLayout
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:orientation="vertical">

        </LinearLayout>

       <LinearLayout
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:orientation="vertical">

       </LinearLayout>


</LinearLayout>

Error: unable to verify the first certificate in nodejs

I faced this issue few days back and this is the approach I followed and it works for me.

For me this was happening when i was trying to fetch data using axios or fetch libraries as i am under a corporate firewall, so we had certain particular certificates which node js certificate store was not able to point to.

So for my loclahost i followed this approach. I created a folder in my project and kept the entire chain of certificates in the folder and in my scripts for dev-server(package.json) i added this alongwith server script so that node js can reference the path.

"dev-server":set NODE_EXTRA_CA_CERTS=certificates/certs-bundle.crt

For my servers(different environments),I created a new environment variable as below and added it.I was using Openshift,but i suppose the concept will be same for others as well.

"name":NODE_EXTRA_CA_CERTS
"value":certificates/certs-bundle.crt

I didn't generate any certificate in my case as the entire chain of certificates was already available for me.

Sublime text 3. How to edit multiple lines?

Use CTRL+D at each line and it will find the matching words and select them then you can use multiple cursors.

You can also use find to find all the occurrences and then it would be multiple cursors too.

how to calculate percentage in python

marks = raw_input('Enter your Obtain marks:')
outof = raw_input('Enter Out of marks:')
marks = int(marks)
outof = int(outof)
per = marks*100/outof
print 'Your Percentage is:'+str(per)

Note : raw_input() function is used to take input from console and its return string formatted value. So we need to convert into integer otherwise it give error of conversion.

How to create the branch from specific commit in different branch

Try

git checkout <commit hash>
git checkout -b new_branch

The commit should only exist once in your tree, not in two separate branches.

This allows you to check out that specific commit and name it what you will.

I get a "An attempt was made to load a program with an incorrect format" error on a SQL Server replication project

Changing the Target Framework in project properties from .NET Framework 4.7.1 to 4.6.2 worked for me.

What's the difference between django OneToOneField and ForeignKey?

OneToOneField: if second table is related with

table2_col1 = models.OneToOneField(table1,on_delete=models.CASCADE, related_name='table1_id')

table2 will contains only one record corresponding to table1's pk value, i.e table2_col1 will have unique value equal to pk of table

table2_col1 == models.ForeignKey(table1, on_delete=models.CASCADE, related_name='table1_id')

table2 may contains more than one record corresponding to table1's pk value.

Spring MVC: how to create a default controller for index page?

One way to achieve it, is by map your welcome-file to your controller request path in the web.xml file:

[web.xml]

<web-app ...

<!-- Index -->
<welcome-file-list>
    <welcome-file>home</welcome-file>
</welcome-file-list>

</web-app>

[LoginController.java]

@Controller("loginController")
public class LoginController{

@RequestMapping("/home")
public String homepage2(ModelMap model, HttpServletRequest request, HttpServletResponse response){
    System.out.println("blablabla2");
    model.addAttribute("sigh", "lesigh");
    return "index";
}

Validate Dynamically Added Input fields

Try using input arrays:

<form action="try.php" method="post">
    <div id="events_wrapper">
        <div id="sub_events">
            <input type="text" name="firstname[]" />                                       
        </div>
    </div>
    <input type="button" id="add_another_event" name="add_another_event" value="Add Another" />
    <input type="submit" name="submit" value="submit" />
</form>

and add this script and jQuery, using foreach() to retrieve the data being $_POST'ed:

<script>                                                                                    
    $(document).ready(function(){
        $("#add_another_event").click(function(){
        var $address = $('#sub_events');
        var num = $('.clonedAddress').length; // there are 5 children inside each address so the prevCloned address * 5 + original
        var newNum = num + 1;
        var newElem = $address.clone().attr('id', 'address' + newNum).addClass('clonedAddress');

        //set all div id's and the input id's
        newElem.children('div').each (function (i) {
            this.id = 'input' + (newNum*5 + i);
        });

        newElem.find('input').each (function () {
            this.id = this.id + newNum;
            this.name = this.name + newNum;
        });

        if (num > 0) {
            $('.clonedAddress:last').after(newElem);
        } else {
            $address.after(newElem);
        }

        $('#btnDel').removeAttr('disabled');
        });

        $("#remove").click(function(){

        });

    });
</script>

MySQL - Trigger for updating same table after insert

It seems that you can't do all this in a trigger. According to the documentation:

Within a stored function or trigger, it is not permitted to modify a table that is already being used (for reading or writing) by the statement that invoked the function or trigger.

According to this answer, it seems that you should:

create a stored procedure, that inserts into/Updates the target table, then updates the other row(s), all in a transaction.

With a stored proc you'll manually commit the changes (insert and update). I haven't done this in MySQL, but this post looks like a good example.

Change font size of UISegmentedControl

Use the Appearance API in iOS 5.0+:

[[UISegmentedControl appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:[UIFont fontWithName:@"STHeitiSC-Medium" size:13.0], UITextAttributeFont, nil] forState:UIControlStateNormal];

Links: http://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIAppearance_Protocol/Reference/Reference.html#//apple_ref/doc/uid/TP40010906

http://www.raywenderlich.com/4344/user-interface-customization-in-ios-5

copy db file with adb pull results in 'permission denied' error

I had the same problem. My work around is to use adb shell and su. Next, copy the file to /sdcard/Download

Then, I can use adb pull to get the file.

Free FTP Library

After lots of investigation in the same issue I found this one to be extremely convenient: https://github.com/flagbug/FlagFtp

For example (try doing this with the standard .net "library" - it will be a real pain) -> Recursively retreving all files on the FTP server:

  public IEnumerable<FtpFileInfo> GetFiles(string server, string user, string password)
    {
        var credentials = new NetworkCredential(user, password);
        var baseUri = new Uri("ftp://" + server + "/");

        var files = new List<FtpFileInfo>();
        AddFilesFromSubdirectory(files, baseUri, credentials);

        return files;
    }

    private void AddFilesFromSubdirectory(List<FtpFileInfo> files, Uri uri, NetworkCredential credentials)
    {
        var client = new FtpClient(credentials);
        var lookedUpFiles = client.GetFiles(uri);
        files.AddRange(lookedUpFiles);

        foreach (var subDirectory in client.GetDirectories(uri))
        {
            AddFilesFromSubdirectory(files, subDirectory.Uri, credentials);
        }
    }

What is the single most influential book every programmer should read?

There are a lot of votes for Steve McConnell's Code Complete, but what about his Software Project Survival Guide book? I think they're both required reading but for different reasons.

How to disable JavaScript in Chrome Developer Tools?

On Mac OS X:

  • Preferences
  • Show advanced settings
  • Press the "content settings" button
  • Scroll to the "JavaScript" section
  • Check the checkbox in front of "Do not allow any site to run JavaScript"

The Chrome Quick JavaScript Switcher extension is a lot easier though :-)

How do I enter a multi-line comment in Perl?

I found it. Perl has multi-line comments:

#!/usr/bin/perl

use strict;

use warnings;

=for comment

Example of multiline comment.

Example of multiline comment.

=cut

print "Multi Line Comment Example \n";

How to make ConstraintLayout work with percentage values?

Constraint Layout 1.0 making a view take up a percentage of the screen required making two guidelines. In Constraint Layout 1.1 it’s been made simpler by allowing you to easily constrain any view to a percentage width or height.

enter image description here

Isn’t this fantastic? All views support layout_constraintWidth_percent and layout_constraintHeight_percent attributes. These will cause the constraint to be fixed at a percentage of the available space. So making a Button or a TextView expand to fill a percent of the screen can be done with a few lines of XML.

For example, if you want to set the width of the button to 70% of screen, you can do it like this:

<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_constraintWidth_percent="0.7" />

Please note that you will have to put the dimension should be used as percentage to 0dp as we have specified android:layout_width to 0dp above.

Similarly, if you want to set the height of the button to 20% of screen, you can do it like this:

<Button
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_constraintHeight_percent="0.2" />

See! we have specified android:layout_height to 0dp this time as we want button to use height as percentage.

Dealing with commas in a CSV file

I used papaParse library to have the CSV file parsed and have the key-value pairs(key/header/first row of CSV file-value).

here is example that I use:

https://codesandbox.io/embed/llqmrp96pm

it has dummy.csv file in there to have the CSV parsing demo.

I've used it within reactJS though it is easy and simple to replicate in app written with any language.

Maven: best way of linking custom external JAR to my project?

Don't use systemPath. Contrary to what people have said here, you can put an external jar in a folder under your checked-out project directory and haven Maven find it like other dependencies. Here are two crucial steps:

  1. Use "mvn install:install-file" with -DlocalRepositoryPath.
  2. Configure a repository to point to that path in your POM.

It is fairly straightforward and you can find a step-by-step example here: http://randomizedsort.blogspot.com/2011/10/configuring-maven-to-use-local-library.html

How to return JSon object

You only have one row to serialize. Try something like this :

List<results> resultRows = new List<results>

resultRows.Add(new results{id = 1, value="ABC", info="ABC"});
resultRows.Add(new results{id = 2, value="XYZ", info="XYZ"});

string json = JavaScriptSerializer.Serialize(new { results = resultRows});
  • Edit to match OP's original json output

** Edit 2 : sorry, but I missed that he was using JSON.NET. Using the JavaScriptSerializer the above code produces this result :

{"results":[{"id":1,"value":"ABC","info":"ABC"},{"id":2,"value":"XYZ","info":"XYZ"}]}

clearing a char array c

Try the following code:

void clean(char *var) {
    int i = 0;
    while(var[i] != '\0') {
        var[i] = '\0';
        i++;
    }
}

How to install python3 version of package via pip on Ubuntu?

Well, on ubuntu 13.10/14.04, things are a little different.

Install

$ sudo apt-get install python3-pip

Install packages

$ sudo pip3 install packagename

NOT pip-3.3 install

How do I hide an element on a click event anywhere outside of the element?

Here is a working CSS/small JS solution based on the answer of Sandeep Pal:

$(document).click(function (e)
{
  if (!$("#noticeMenu").is(e.target) && $("#noticeMenu").has(e.target).length == 0)
  {
   $("#menu-toggle3").prop('checked', false);
  }
});

Try it out by clicking the checkbox and then outside of the menu:

https://jsfiddle.net/qo90txr8/

How to insert a character in a string at a certain position?

int j = 123456;
String x = Integer.toString(j);
x = x.substring(0, 4) + "." + x.substring(4, x.length());

MongoDb query condition on comparing 2 fields

You can use $expr ( 3.6 mongo version operator ) to use aggregation functions in regular query.

Compare query operators vs aggregation comparison operators.

Regular Query:

db.T.find({$expr:{$gt:["$Grade1", "$Grade2"]}})

Aggregation Query:

db.T.aggregate({$match:{$expr:{$gt:["$Grade1", "$Grade2"]}}})

Using Java generics for JPA findAll() query with WHERE clause

Hat tip to Adam Bien if you don't want to use createQuery with a String and want type safety:

 @PersistenceContext
 EntityManager em;

 public List<ConfigurationEntry> allEntries() {
        CriteriaBuilder cb = em.getCriteriaBuilder();
        CriteriaQuery<ConfigurationEntry> cq = cb.createQuery(ConfigurationEntry.class);
        Root<ConfigurationEntry> rootEntry = cq.from(ConfigurationEntry.class);
        CriteriaQuery<ConfigurationEntry> all = cq.select(rootEntry);
        TypedQuery<ConfigurationEntry> allQuery = em.createQuery(all);
        return allQuery.getResultList();
 }

http://www.adam-bien.com/roller/abien/entry/selecting_all_jpa_entities_as

Convert comma separated string of ints to int array

Without using a lambda function and for valid inputs only, I think it's clearer to do this:

Array.ConvertAll<string, int>(value.Split(','), Convert.ToInt32);

Does Google Chrome work with Selenium IDE (as Firefox does)?

No, Google Chrome does not work with Selenium IDE. As Selenium IDE is a Firefox plugin it works only with FF.

According to your last portion of question: Or is there any alternative tool which can work with Chrome? The possible answer is as follows:

You can use Sahi with Chrome. Sahi Test Automation tool supports Chrome, Firefox and IE. You can visit for details:

http://sahi.co.in/

Apache Cordova - uninstall globally

Try sudo npm uninstall cordova -g to uninstall it globally and then just npm install cordova without the -g flag after cding to the local app directory

How to cast a double to an int in Java by rounding it down?

try with this, This is simple

double x= 20.22889909008;
int a = (int) x;

this will return a=20

or try with this:-

Double x = 20.22889909008;
Integer a = x.intValue();

this will return a=20

or try with this:-

double x= 20.22889909008;
System.out.println("===="+(int)x);

this will return ===20

may be these code will help you.

What is "loose coupling?" Please provide examples

You can think of (tight or loose) coupling as being literally the amount of effort it would take you to separate a particular class from its reliance on another class. For example, if every method in your class had a little finally block at the bottom where you made a call to Log4Net to log something, then you would say your class was tightly coupled to Log4Net. If your class instead contained a private method named LogSomething which was the only place that called the Log4Net component (and the other methods all called LogSomething instead), then you would say your class was loosely coupled to Log4Net (because it wouldn't take much effort to pull Log4Net out and replace it with something else).

Can an ASP.NET MVC controller return an Image?

Below code utilizes System.Drawing.Bitmap to load the image.

using System.Drawing;
using System.Drawing.Imaging;

public IActionResult Get()
{
    string filename = "Image/test.jpg";
    var bitmap = new Bitmap(filename);

    var ms = new System.IO.MemoryStream();
    bitmap.Save(ms, ImageFormat.Jpeg);
    ms.Position = 0;
    return new FileStreamResult(ms, "image/jpeg");
}

Spring Boot - How to log all requests and responses with exceptions in single place?

I had defined logging level in application.properties to print requests/responses, method url in the log file

logging.level.org.springframework.web=DEBUG
logging.level.org.hibernate.SQL=INFO
logging.file=D:/log/myapp.log

I had used Spring Boot.

How do I create delegates in Objective-C?

Disclaimer: this is the Swift version of how to create a delegate.

So, what are delegates? …in software development, there are general reusable solution architectures that help to solve commonly occurring problems within a given context, these “templates”, so to speak, are best known as design patterns. Delegates are a design pattern that allows one object to send messages to another object when a specific event happens. Imagine an object A calls an object B to perform an action. Once the action is complete, object A should know that B has completed the task and take necessary action, this can be achieved with the help of delegates!

For a better explanation, I am going to show you how to create a custom delegate that passes data between classes, with Swift in a simple application,start by downloading or cloning this starter project and run it!

You can see an app with two classes, ViewController A and ViewController B. B has two views that on tap changes the background color of the ViewController, nothing too complicated right? well now let’s think in an easy way to also change the background color of class A when the views on class B are tapped.

The problem is that this views are part of class B and have no idea about class A, so we need to find a way to communicate between this two classes, and that’s where delegation shines. I divided the implementation into 6 steps so you can use this as a cheat sheet when you need it.

step 1: Look for the pragma mark step 1 in ClassBVC file and add this

//MARK: step 1 Add Protocol here.
protocol ClassBVCDelegate: class {
func changeBackgroundColor(_ color: UIColor?)
}

The first step is to create a protocol, in this case, we will create the protocol in class B, inside the protocol you can create as many functions that you want based on the requirements of your implementation. In this case, we just have one simple function that accepts an optional UIColor as an argument. Is a good practice to name your protocols adding the word delegate at the end of the class name, in this case, ClassBVCDelegate.

step 2: Look for the pragma mark step 2 in ClassVBC and add this

//MARK: step 2 Create a delegate property here.
weak var delegate: ClassBVCDelegate?

Here we just create a delegate property for the class, this property must adopt the protocol type, and it should be optional. Also, you should add the weak keyword before the property to avoid retain cycles and potential memory leaks, if you don’t know what that means don’t worry for now, just remember to add this keyword.

step 3: Look for the pragma mark step 3 inside the handleTap method in ClassBVC and add this

//MARK: step 3 Add the delegate method call here.
delegate?.changeBackgroundColor(tapGesture.view?.backgroundColor)

One thing that you should know, run the app and tap on any view, you won’t see any new behavior and that’s correct but the thing that I want to point out is that the app it’s not crashing when the delegate is called, and it’s because we create it as an optional value and that’s why it won’t crash even the delegated doesn’t exist yet. Let’s now go to ClassAVC file and make it, the delegated.

step 4: Look for the pragma mark step 4 inside the handleTap method in ClassAVC and add this next to your class type like this.

//MARK: step 4 conform the protocol here.
class ClassAVC: UIViewController, ClassBVCDelegate {
}

Now ClassAVC adopted the ClassBVCDelegate protocol, you can see that your compiler is giving you an error that says “Type ‘ClassAVC does not conform to protocol ‘ClassBVCDelegate’ and this only means that you didn’t use the methods of the protocol yet, imagine that when class A adopts the protocol is like signing a contract with class B and this contract says “Any class adopting me MUST use my functions!”

Quick note: If you come from an Objective-C background you are probably thinking that you can also shut up that error making that method optional, but for my surprise, and probably yours, Swift language does not support optional protocols, if you want to do it you can create an extension for your protocol or use the @objc keyword in your protocol implementation.

Personally, If I have to create a protocol with different optional methods I would prefer to break it into different protocols, that way I will follow the concept of giving one single responsibility to my objects, but it can vary based on the specific implementation.

here is a good article about optional methods.

step 5: Look for the pragma mark step 5 inside the prepare for segue method and add this

//MARK: step 5 create a reference of Class B and bind them through the `prepareforsegue` method.
if let nav = segue.destination as? UINavigationController, let classBVC = nav.topViewController as? ClassBVC {
classBVC.delegate = self
}

Here we are just creating an instance of ClassBVC and assign its delegate to self, but what is self here? well, self is the ClassAVC which has been delegated!

step 6: Finally, look for the pragma step 6 in ClassAVC and let’s use the functions of the protocol, start typing func changeBackgroundColor and you will see that it’s auto-completing it for you. You can add any implementation inside it, in this example, we will just change the background color, add this.

//MARK: step 6 finally use the method of the contract
func changeBackgroundColor(_ color: UIColor?) {
view.backgroundColor = color
}

Now run the app!

Delegates are everywhere and you probably use them without even notice, if you create a tableview in the past you used delegation, many classes of UIKIT works around them and many other frameworks too, they solve these main problems.

  • Avoid tight coupling of objects.
  • Modify behavior and appearance without the need to subclass objects.
  • Allow tasks to be handled off to any arbitrary object.

Congratulations, you just implement a custom delegate, I know that you are probably thinking, so much trouble just for this? well, delegation is a very important design pattern to understand if you want to become an iOS developer, and always keep in mind that they have one to one relationship between objects.

You can see the original tutorial here

Bash script processing limited number of commands in parallel

Use the wait built-in:

process1 &
process2 &
process3 &
process4 &
wait
process5 &
process6 &
process7 &
process8 &
wait

For the above example, 4 processes process1 ... process4 would be started in the background, and the shell would wait until those are completed before starting the next set.

From the GNU manual:

wait [jobspec or pid ...]

Wait until the child process specified by each process ID pid or job specification jobspec exits and return the exit status of the last command waited for. If a job spec is given, all processes in the job are waited for. If no arguments are given, all currently active child processes are waited for, and the return status is zero. If neither jobspec nor pid specifies an active child process of the shell, the return status is 127.

How can you test if an object has a specific property?

For me MyProperty" -in $MyObject.PSobject.Properties.Name didn't work, however

$MyObject.PSobject.Properties.Name.Contains("MyProperty")

works

How to find the length of an array in shell?

Assuming bash:

~> declare -a foo
~> foo[0]="foo"
~> foo[1]="bar"
~> foo[2]="baz"
~> echo ${#foo[*]}
3

So, ${#ARRAY[*]} expands to the length of the array ARRAY.

Is a URL allowed to contain a space?

Can someone point to an RFC indicating that a URL with a space must be encoded?

URIs, and thus URLs, are defined in RFC 3986.

If you look at the grammar defined over there you will eventually note that a space character never can be part of a syntactically legal URL, thus the term "URL with a space" is a contradiction in itself.

Sourcetree - undo unpushed commits

If you want to delete a commit you can do it as part of an interactive rebase. But do it with caution, so you don't end up messing up your repo.

In Sourcetree:

  1. Right click a commit that's older than the one you want to delete, and choose "Rebase children of xxxx interactively...". The one you click will be your "base" and you can make changes to every commit made after that one.

Screenshot-1

  1. In the new window, select the commit you want gone, and press the "Delete"-button at the bottom, or right click the commit and click "Delete commit".
  2. List item
  3. Click "OK" (or "Cancel" if you want to abort).

Check out this Atlassian blog post for more on interactive rebasing in Sourcetree.

Calculating difference between two timestamps in Oracle in milliseconds

I know that this has been exhaustively answered, but I wanted to share my FUNCTION with everyone. It gives you the option to choose if you want your answer to be in days, hours, minutes, seconds, or milliseconds. You can modify it to fit your needs.

CREATE OR REPLACE FUNCTION Return_Elapsed_Time (start_ IN TIMESTAMP, end_ IN TIMESTAMP DEFAULT SYSTIMESTAMP, syntax_ IN NUMBER DEFAULT NULL) RETURN VARCHAR2 IS
    FUNCTION Core (start_ IN TIMESTAMP, end_ IN TIMESTAMP DEFAULT SYSTIMESTAMP, syntax_ IN NUMBER DEFAULT NULL) RETURN VARCHAR2 IS
        day_ VARCHAR2(7); /* This means this FUNCTION only supports up to 99 days */
        hour_ VARCHAR2(9); /* This means this FUNCTION only supports up to 999 hours, which is over 41 days */
        minute_ VARCHAR2(12); /* This means this FUNCTION only supports up to 9999 minutes, which is over 17 days */
        second_ VARCHAR2(18); /* This means this FUNCTION only supports up to 999999 seconds, which is over 11 days */
        msecond_ VARCHAR2(22); /* This means this FUNCTION only supports up to 999999999 milliseconds, which is over 11 days */
        d1_ NUMBER;
        h1_ NUMBER;
        m1_ NUMBER;
        s1_ NUMBER;
        ms_ NUMBER;
        /* If you choose 1, you only get seconds. If you choose 2, you get minutes and seconds etc. */
        precision_ NUMBER; /* 0 => milliseconds; 1 => seconds; 2 => minutes; 3 => hours; 4 => days */
        format_ VARCHAR2(2) := ', ';
        return_ VARCHAR2(50);
    BEGIN
        IF (syntax_ IS NULL) THEN
            precision_ := 0;
        ELSE
            IF (syntax_ = 0) THEN
                precision_ := 0;
            ELSIF (syntax_ = 1) THEN
                precision_ := 1;
            ELSIF (syntax_ = 2) THEN
                precision_ := 2;
            ELSIF (syntax_ = 3) THEN
                precision_ := 3;
            ELSIF (syntax_ = 4) THEN
                precision_ := 4;
            ELSE 
                precision_ := 0;
            END IF;
        END IF;
        SELECT EXTRACT(DAY FROM (end_ - start_)) INTO d1_ FROM DUAL;
        SELECT EXTRACT(HOUR FROM (end_ - start_)) INTO h1_ FROM DUAL;
        SELECT EXTRACT(MINUTE FROM (end_ - start_)) INTO m1_ FROM DUAL;
        SELECT EXTRACT(SECOND FROM (end_ - start_)) INTO s1_ FROM DUAL;
        IF (precision_ = 4) THEN
            IF (d1_ = 1) THEN
                day_ := ' day';
            ELSE
                day_ := ' days';
            END IF;
            IF (h1_ = 1) THEN
                hour_ := ' hour';
            ELSE
                hour_ := ' hours';
            END IF;
            IF (m1_ = 1) THEN
                minute_ := ' minute';
            ELSE
                minute_ := ' minutes';
            END IF;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := d1_ || day_ || format_ || h1_ || hour_ || format_ || m1_ || minute_ || format_ || s1_ || second_;
            RETURN return_;
        ELSIF (precision_ = 3) THEN
            h1_ := (d1_ * 24) + h1_;
            IF (h1_ = 1) THEN
                hour_ := ' hour';
            ELSE
                hour_ := ' hours';
            END IF;
            IF (m1_ = 1) THEN
                minute_ := ' minute';
            ELSE
                minute_ := ' minutes';
            END IF;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := h1_ || hour_ || format_ || m1_ || minute_ || format_ || s1_ || second_;
            RETURN return_;
        ELSIF (precision_ = 2) THEN
            m1_ := (((d1_ * 24) + h1_) * 60) + m1_;
            IF (m1_ = 1) THEN
                minute_ := ' minute';
            ELSE
                minute_ := ' minutes';
            END IF;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := m1_ || minute_ || format_ || s1_ || second_;
            RETURN return_;
        ELSIF (precision_ = 1) THEN
            s1_ := (((((d1_ * 24) + h1_) * 60) + m1_) * 60) + s1_;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := s1_ || second_;
            RETURN return_;
        ELSE
            ms_ := ((((((d1_ * 24) + h1_) * 60) + m1_) * 60) + s1_) * 1000;
            IF (ms_ = 1) THEN
                msecond_ := ' millisecond';
            ELSE
                msecond_ := ' milliseconds';
            END IF;
            return_ := ms_ || msecond_;
            RETURN return_;
        END IF;
    END Core;
BEGIN
    RETURN(Core(start_, end_, syntax_));
END Return_Elapsed_Time;

For example, if I called this function right now (12.10.2018 11:17:00.00) using Return_Elapsed_Time(TO_TIMESTAMP('12.04.2017 12:00:00.00', 'DD.MM.YYYY HH24:MI:SS.FF'),SYSTIMESTAMP), it should return something like:

47344620000 milliseconds

How to open a workbook specifying its path

You can also open a required file through a prompt, This helps when you want to select file from different path and different file.

Sub openwb()
Dim wkbk As Workbook
Dim NewFile As Variant

NewFile = Application.GetOpenFilename("microsoft excel files (*.xlsm*), *.xlsm*")

If NewFile <> False Then
Set wkbk = Workbooks.Open(NewFile)
End If
End Sub

Apache 2.4 - Request exceeded the limit of 10 internal redirects due to probable configuration error

Solved this by adding following

RewriteCond %{ENV:REDIRECT_STATUS} 200 [OR]
 RewriteCond %{REQUEST_FILENAME} -f [OR]
 RewriteCond %{REQUEST_FILENAME} -d
 RewriteRule ^ - [L]

How to access List elements

Learn python the hard way ex 34

try this

animals = ['bear' , 'python' , 'peacock', 'kangaroo' , 'whale' , 'platypus']

# print "The first (1st) animal is at 0 and is a bear." 

for i in range(len(animals)):
    print "The %d animal is at %d and is a %s" % (i+1 ,i, animals[i])

# "The animal at 0 is the 1st animal and is a bear."

for i in range(len(animals)):
    print "The animal at %d is the %d and is a %s " % (i, i+1, animals[i])

Increasing the maximum post size

I had a situation when variables went missing from POST and all of the above answers didn't help. It turned out that

max_input_vars=1000

was set by default and POST in question had more than that. This may be a problem.

Linux delete file with size 0

find . -type f -empty -exec rm -f {} \;

What is the difference between AF_INET and PF_INET in socket programming?

In fact, AF_ and PF_ are the same thing. There are some words on Wikipedia will clear your confusion

The original design concept of the socket interface distinguished between protocol types (families) and the specific address types that each may use. It was envisioned that a protocol family may have several address types. Address types were defined by additional symbolic constants, using the prefix AF_ instead of PF_. The AF_-identifiers are intended for all data structures that specifically deal with the address type and not the protocol family. However, this concept of separation of protocol and address type has not found implementation support and the AF_-constants were simply defined by the corresponding protocol identifier, rendering the distinction between AF_ versus PF_ constants a technical argument of no significant practical consequence. Indeed, much confusion exists in the proper usage of both forms.

Allow multi-line in EditText view in Android?

 <EditText
           android:id="@id/editText" //id of editText
           android:gravity="start"   // Where to start Typing
           android:inputType="textMultiLine" // multiline
           android:imeOptions="actionDone" // Keyboard done button
           android:minLines="5" // Min Line of editText
           android:hint="@string/Enter Data" // Hint in editText
           android:layout_width="match_parent" //width editText
           android:layout_height="wrap_content" //height editText
           /> 

XPath Query: get attribute href from a tag

The answer shared by @mockinterface is correct. Although I would like to add my 2 cents to it.

If someone is using frameworks like scrapy the you will have to use /html/body//a[contains(@href,'com')][2]/@href along with get() like this:

response.xpath('//a[contains(@href,'com')][2]/@href').get()

How do I execute a MS SQL Server stored procedure in java/jsp, returning table data?

FWIW, sp_test will not be returning anything but an integer (all SQL Server stored procs just return an integer) and no result sets on the wire (since no SELECT statements). To get the output of the PRINT statements, you normally use the InfoMessage event on the connection (not the command) in ADO.NET.

Absolute position of an element on the screen using jQuery

For the absolute coordinates of any jquery element I wrote this function, it probably doesnt work for all css position types but maybe its a good start for someone ..

function AbsoluteCoordinates($element) {
    var sTop = $(window).scrollTop();
    var sLeft = $(window).scrollLeft();
    var w = $element.width();
    var h = $element.height();
    var offset = $element.offset(); 
    var $p = $element;
    while(typeof $p == 'object') {
        var pOffset = $p.parent().offset();
        if(typeof pOffset == 'undefined') break;
        offset.left = offset.left + (pOffset.left);
        offset.top = offset.top + (pOffset.top);
        $p = $p.parent();
    }

    var pos = {
          left: offset.left + sLeft,
          right: offset.left + w + sLeft,
          top:  offset.top + sTop,
          bottom: offset.top + h + sTop,
    }
    pos.tl = { x: pos.left, y: pos.top };
    pos.tr = { x: pos.right, y: pos.top };
    pos.bl = { x: pos.left, y: pos.bottom };
    pos.br = { x: pos.right, y: pos.bottom };
    //console.log( 'left: ' + pos.left + ' - right: ' + pos.right +' - top: ' + pos.top +' - bottom: ' + pos.bottom  );
    return pos;
}

How to sum a variable by group

using cast instead of recast (note 'Frequency' is now 'value')

df  <- data.frame(Category = c("First","First","First","Second","Third","Third","Second")
                  , value = c(10,15,5,2,14,20,3))

install.packages("reshape")

result<-cast(df, Category ~ . ,fun.aggregate=sum)

to get:

Category (all)
First     30
Second    5
Third     34

Java: Integer equals vs. ==

Integer refers to the reference, that is, when comparing references you're comparing if they point to the same object, not value. Hence, the issue you're seeing. The reason it works so well with plain int types is that it unboxes the value contained by the Integer.

May I add that if you're doing what you're doing, why have the if statement to begin with?

mismatch = ( cdiCt != null && cdsCt != null && !cdiCt.equals( cdsCt ) );

Git push failed, "Non-fast forward updates were rejected"

You can add --force-with-lease to the command, it will works.

git push --force-with-lease

--force is destructive because it unconditionally overwrites the remote repository with whatever you have locally. But --force-with-lease ensure you don't overwrite other's work.

See more info here.

Set Text property of asp:label in Javascript PROPER way

Use the following code

<span id="sptext" runat="server"></span>

Java Script

document.getElementById('<%=sptext'%>).innerHTML='change text';

C#

sptext.innerHTML

Find a value anywhere in a database

If you have phpMyAdmin installed use its Search feature.

Select your DataBase.

Be sure you do have selected DataBase, not a table, otherwise you'll get a completely different search dialog.

  1. Click Search tab
  2. List item Choose the search term you want
  3. Choose the tables to search

How to keep a Python script output window open?

Start the script from already open cmd window or at the end of script add something like this, in Python 2:

 raw_input("Press enter to exit ;)")

Or, in Python 3:

input("Press enter to exit ;)")

Find the closest ancestor element that has a specific class

@rvighne solution works well, but as identified in the comments ParentElement and ClassList both have compatibility issues. To make it more compatible, I have used:

function findAncestor (el, cls) {
    while ((el = el.parentNode) && el.className.indexOf(cls) < 0);
    return el;
}
  • parentNode property instead of the parentElement property
  • indexOf method on the className property instead of the contains method on the classList property.

Of course, indexOf is simply looking for the presence of that string, it does not care if it is the whole string or not. So if you had another element with class 'ancestor-type' it would still return as having found 'ancestor', if this is a problem for you, perhaps you can use regexp to find an exact match.

CSS container div not getting height

The best and the most bulletproof solution is to add ::before and ::after pseudoelements to the container. So if you have for example a list like:

<ul class="clearfix">
    <li></li>
    <li></li>
    <li></li>
</ul>

And every elements in the list has float:left property, then you should add to your css:

.clearfix::after, .clearfix::before {
     content: '';
     clear: both;
     display: table;
}

Or you could try display:inline-block; property, then you don't need to add any clearfix.

How can I add an item to a ListBox in C# and WinForms?

list.Items.add(new ListBoxItem("name", "value"));

The internal (default) data structure of the ListBox is the ListBoxItem.

Bash integer comparison

This script works!

#/bin/bash
if [[ ( "$#" < 1 ) || ( !( "$1" == 1 ) && !( "$1" == 0 ) ) ]] ; then
    echo this script requires a 1 or 0 as first parameter.
else
    echo "first parameter is $1"
    xinput set-prop 12 "Device Enabled" $0
fi

But this also works, and in addition keeps the logic of the OP, since the question is about calculations. Here it is with only arithmetic expressions:

#/bin/bash
if (( $# )) && (( $1 == 0 || $1 == 1 )); then
    echo "first parameter is $1"
    xinput set-prop 12 "Device Enabled" $0
else
    echo this script requires a 1 or 0 as first parameter.
fi

The output is the same1:

$ ./tmp.sh 
this script requires a 1 or 0 as first parameter.

$ ./tmp.sh 0
first parameter is 0

$ ./tmp.sh 1
first parameter is 1

$ ./tmp.sh 2
this script requires a 1 or 0 as first parameter.

[1] the second fails if the first argument is a string

Facebook page automatic "like" URL (for QR Code)

In my opinion, it is not possible for the like button (and I hope it is not possible).

But, you can trigger a custom OpenGraph v2 action, or display a like button linked to your facebook page.

What does "Could not find or load main class" mean?

I had a weird one:

Error: Could not find or load main class mypackage.App

It turned out I had a reference to POM (parent) coded up in my project's pom.xml file (my project's pom.xml was pointing to a parent pom.xml) and the relativePath was off/wrong.

Below is a partial of my project's pom.xml file:

<parent>
    <groupId>myGroupId</groupId>
    <artifactId>pom-parent</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <relativePath>../badPathHere/pom.xml</relativePath>
</parent>

Once I resolved the POM relativePath, the error went away.

Go figure.

How to get current user, and how to use User class in MVC5?

If you want the ApplicationUser object in one line of code (if you have the latest ASP.NET Identity installed), try:

ApplicationUser user = System.Web.HttpContext.Current.GetOwinContext().GetUserManager<ApplicationUserManager>().FindById(System.Web.HttpContext.Current.User.Identity.GetUserId());

You'll need the following using statements:

using Microsoft.AspNet.Identity;
using Microsoft.AspNet.Identity.Owin;

How to pass parameter to a promise function

You can use .bind() to pass the param(this) to the function.

var someFunction =function(resolve, reject) {
  /* get username, password*/
  var username=this.username;
  var password=this.password;
  if ( /* everything turned out fine */ ) {
    resolve("Stuff worked!");
  } else {
    reject(Error("It broke"));
  }
}
var promise=new Promise(someFunction.bind({username:"your username",password:"your password"}));

How to switch to new window in Selenium for Python?

window_handles should give you the references to all open windows.

this is what the docu has to say about switching windows.

What is the difference between background and background-color

background will supercede all previous background-color, background-image, etc. specifications. It's basically a shorthand, but a reset as well.

I will sometimes use it to overwrite previous background specifications in template customizations, where I would want the following:

background: white url(images/image1.jpg) top left repeat;

to be the following:

background: black;

So, all parameters (background-image, background-position, background-repeat) will reset to their default values.

how to bind img src in angular 2 in ngFor?

Angular 2, 4 and Angular 5 compatible!

You have provided so few details, so I'll try to answer your question without them.

You can use Interpolation:

<img src={{imagePath}} />

Or you can use a template expression:

<img [src]="imagePath" />

In a ngFor loop it might look like this:

<div *ngFor="let student of students">
   <img src={{student.ImagePath}} />
</div>

converting a base 64 string to an image and saving it

In a similar scenario what worked for me was the following:

byte[] bytes = Convert.FromBase64String(Base64String);    
ImageTagId.ImageUrl = "data:image/jpeg;base64," + Convert.ToBase64String(bytes);

ImageTagId is the ID of the ASP image tag.

Is it possible to disable scrolling on a ViewPager

A simple solution is to create your own subclass of ViewPager that has a private boolean flag, isPagingEnabled. Then override the onTouchEvent and onInterceptTouchEvent methods. If isPagingEnabled equals true invoke the super method, otherwise return.

public class CustomViewPager extends ViewPager {

    private boolean isPagingEnabled = true;

    public CustomViewPager(Context context) {
        super(context);
    }

    public CustomViewPager(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        return this.isPagingEnabled && super.onTouchEvent(event);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        return this.isPagingEnabled && super.onInterceptTouchEvent(event);
    }

    public void setPagingEnabled(boolean b) {
        this.isPagingEnabled = b;
    }
}

Then in your Layout.XML file replace any <com.android.support.V4.ViewPager> tags with <com.yourpackage.CustomViewPager> tags.

This code was adapted from this blog post.

Convert base64 string to ArrayBuffer

Goran.it's answer does not work because of unicode problem in javascript - https://developer.mozilla.org/en-US/docs/Web/API/WindowBase64/Base64_encoding_and_decoding.

I ended up using the function given on Daniel Guerrero's blog: http://blog.danguer.com/2011/10/24/base64-binary-decoding-in-javascript/

Function is listed on github link: https://github.com/danguer/blog-examples/blob/master/js/base64-binary.js

Use these lines

var uintArray = Base64Binary.decode(base64_string);  
var byteArray = Base64Binary.decodeArrayBuffer(base64_string); 

What is the meaning of ImagePullBackOff status on a Kubernetes pod?

I too had this problem, when I checked I image that I was pulling from a private registry was removed If we describe pod it will show pulling event and the image it's trying to pull

kubectl describe pod <POD_NAME>

Events:
 Type     Reason   Age                  From              Message
 ----     ------   ----                 ----              -------
 Normal   Pulling  18h (x35 over 20h)   kubelet, gsk-kub  Pulling image "registeryName:tag"
 Normal   BackOff  11m (x822 over 20h)  kubelet, gsk-kub  Back-off pulling image "registeryName:tag"
 Warning  Failed   91s (x858 over 20h)  kubelet, gsk-kub  Error: ImagePullBackOff

What's the difference between F5 refresh and Shift+F5 in Google Chrome browser?

It ignores the cached content when refreshing...

https://support.google.com/a/answer/3001912?hl=en

F5 or Control + R = Reload the current page
Control+Shift+R or Shift + F5 = Reload your current page, ignoring cached content

Count all duplicates of each value

This is quite simple.

Assuming the data is stored in a column called A in a table called T, you can use

select A, count(A) from T group by A