Programs & Examples On #Redirectstandardoutput

UTF-8 output from PowerShell

This is a bug in .NET. When PowerShell launches, it caches the output handle (Console.Out). The Encoding property of that text writer does not pick up the value StandardOutputEncoding property.

When you change it from within PowerShell, the Encoding property of the cached output writer returns the cached value, so the output is still encoded with the default encoding.

As a workaround, I would suggest not changing the encoding. It will be returned to you as a Unicode string, at which point you can manage the encoding yourself.

Caching example:

102 [C:\Users\leeholm]
>> $r1 = [Console]::Out

103 [C:\Users\leeholm]
>> $r1

Encoding                                          FormatProvider
--------                                          --------------
System.Text.SBCSCodePageEncoding                  en-US

104 [C:\Users\leeholm]
>> [Console]::OutputEncoding = [System.Text.Encoding]::UTF8

105 [C:\Users\leeholm]
>> $r1

Encoding                                          FormatProvider
--------                                          --------------
System.Text.SBCSCodePageEncoding                  en-US

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

In order to append to a file you'll need to use a slightly different approach. You can still redirect an individual process' standard error and standard output to a file, but in order to append it to a file you'll need to do one of these things:

  1. Read the stdout/stderr file contents created by Start-Process
  2. Not use Start-Process and use the call operator, &
  3. Not use Start-Process and start the process with .NET objects

The first way would look like this:

$myLog = "C:\File.log"
$stdErrLog = "C:\stderr.log"
$stdOutLog = "C:\stdout.log"
Start-Process -File myjob.bat -RedirectStandardOutput $stdOutLog -RedirectStandardError $stdErrLog -wait
Get-Content $stdErrLog, $stdOutLog | Out-File $myLog -Append

The second way would look like this:

& myjob.bat 2>&1 >> C:\MyLog.txt

Or this:

& myjob.bat 2>&1 | Out-File C:\MyLog.txt -Append

The third way:

$pinfo = New-Object System.Diagnostics.ProcessStartInfo
$pinfo.FileName = "myjob.bat"
$pinfo.RedirectStandardError = $true
$pinfo.RedirectStandardOutput = $true
$pinfo.UseShellExecute = $false
$pinfo.Arguments = ""
$p = New-Object System.Diagnostics.Process
$p.StartInfo = $pinfo
$p.Start() | Out-Null
$output = $p.StandardOutput.ReadToEnd()
$output += $p.StandardError.ReadToEnd()
$output | Out-File $myLog -Append

Capturing standard out and error with Start-Process

Here is my version of function that is returning standard System.Diagnostics.Process with 3 new properties

Function Execute-Command ($commandTitle, $commandPath, $commandArguments)
    Try {
        $pinfo = New-Object System.Diagnostics.ProcessStartInfo
        $pinfo.FileName = $commandPath
        $pinfo.RedirectStandardError = $true
        $pinfo.RedirectStandardOutput = $true
        $pinfo.UseShellExecute = $false
        $pinfo.WindowStyle = 'Hidden'
        $pinfo.CreateNoWindow = $True
        $pinfo.Arguments = $commandArguments
        $p = New-Object System.Diagnostics.Process
        $p.StartInfo = $pinfo
        $p.Start() | Out-Null
        $stdout = $p.StandardOutput.ReadToEnd()
        $stderr = $p.StandardError.ReadToEnd()
        $p | Add-Member "commandTitle" $commandTitle
        $p | Add-Member "stdout" $stdout
        $p | Add-Member "stderr" $stderr
    Catch {

Hide console window from Process.Start C#

This should work, try;

Add a System Reference.

using System.Diagnostics;

Then use this code to run your command in a hiden CMD Window.

Process cmd = new Process();
cmd.StartInfo.FileName = "cmd.exe";
cmd.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
cmd.StartInfo.Arguments = "Enter your command here";

How to start a Process as administrator mode in C#

This is a clear answer to your question: How do I force my .NET application to run as administrator?


Right Click on project -> Add new item -> Application Manifest File

Then in that file change a line like this:

<requestedExecutionLevel level="requireAdministrator" uiAccess="false" />

Compile and run!

Error in Process.Start() -- The system cannot find the file specified

Also, if your PATH's dir is enclosed in quotes, it will work from the command prompt but you'll get the same error message

I.e. this causes an issue with Process.Start() not finding your exe:

PATH="C:\my program\bin";c:\windows\system32

Maybe it helps someone.

How can I Convert HTML to Text in C#?

I have recently blogged on a solution that worked for me by using a Markdown XSLT file to transform the HTML Source. The HTML source will of course need to be valid XML first

How to execute an .SQL script file using c#

There are two points to considerate.

1) This source code worked for me:

private static string Execute(string credentials, string scriptDir, string scriptFilename)
  Process process = new Process();
  process.StartInfo.UseShellExecute = false;
  process.StartInfo.WorkingDirectory = scriptDir;
  process.StartInfo.RedirectStandardOutput = true;
  process.StartInfo.FileName = "sqlplus";
  process.StartInfo.Arguments = string.Format("{0} @{1}", credentials, scriptFilename);
  process.StartInfo.CreateNoWindow = true;

  string output = process.StandardOutput.ReadToEnd();

  return output;

I set the working directory to the script directory, so that sub scripts within the script also work.

Call it e.g. as Execute("usr/pwd@service", "c:\myscripts", "script.sql")

2) You have to finalize your SQL script with the statement EXIT;

How to execute a .bat file from a C# windows form app?

Here is what you are looking for:

Service hangs up at WaitForExit after calling batch file

It's about a question as to why a service can't execute a file, but it shows all the code necessary to do so.

How to spawn a process and capture its STDOUT in .NET?

The answer from Judah did not work for me (or is not complete) as the application was exiting after the first BeginOutputReadLine();

This works for me as a complete snippet, reading the constant output of a ping:

        var process = new Process();
        process.StartInfo.FileName = "ping";
        process.StartInfo.Arguments = " -t";
        process.StartInfo.RedirectStandardOutput = true;
        process.StartInfo.UseShellExecute = false;
        process.OutputDataReceived += (sender, a) => Console.WriteLine(a.Data);

ProcessStartInfo hanging on "WaitForExit"? Why?

This is a more modern awaitable, Task Parallel Library (TPL) based solution for .NET 4.5 and above.

Usage Example

    var exitCode = await StartProcess(
    Console.WriteLine($"Process Exited with Exit Code {exitCode}!");
catch (TaskCanceledException)
    Console.WriteLine("Process Timed Out!");


public static async Task<int> StartProcess(
    string filename,
    string arguments,
    string workingDirectory= null,
    int? timeout = null,
    TextWriter outputTextWriter = null,
    TextWriter errorTextWriter = null)
    using (var process = new Process()
        StartInfo = new ProcessStartInfo()
            CreateNoWindow = true,
            Arguments = arguments,
            FileName = filename,
            RedirectStandardOutput = outputTextWriter != null,
            RedirectStandardError = errorTextWriter != null,
            UseShellExecute = false,
            WorkingDirectory = workingDirectory
        var cancellationTokenSource = timeout.HasValue ?
            new CancellationTokenSource(timeout.Value) :
            new CancellationTokenSource();


        var tasks = new List<Task>(3) { process.WaitForExitAsync(cancellationTokenSource.Token) };
        if (outputTextWriter != null)
                x =>
                    process.OutputDataReceived += x;
                x => process.OutputDataReceived -= x,

        if (errorTextWriter != null)
                x =>
                    process.ErrorDataReceived += x;
                x => process.ErrorDataReceived -= x,

        await Task.WhenAll(tasks);
        return process.ExitCode;

/// <summary>
/// Waits asynchronously for the process to exit.
/// </summary>
/// <param name="process">The process to wait for cancellation.</param>
/// <param name="cancellationToken">A cancellation token. If invoked, the task will return
/// immediately as cancelled.</param>
/// <returns>A Task representing waiting for the process to end.</returns>
public static Task WaitForExitAsync(
    this Process process,
    CancellationToken cancellationToken = default(CancellationToken))
    process.EnableRaisingEvents = true;

    var taskCompletionSource = new TaskCompletionSource<object>();

    EventHandler handler = null;
    handler = (sender, args) =>
        process.Exited -= handler;
    process.Exited += handler;

    if (cancellationToken != default(CancellationToken))
            () =>
                process.Exited -= handler;

    return taskCompletionSource.Task;

/// <summary>
/// Reads the data from the specified data recieved event and writes it to the
/// <paramref name="textWriter"/>.
/// </summary>
/// <param name="addHandler">Adds the event handler.</param>
/// <param name="removeHandler">Removes the event handler.</param>
/// <param name="textWriter">The text writer.</param>
/// <param name="cancellationToken">The cancellation token.</param>
/// <returns>A task representing the asynchronous operation.</returns>
public static Task ReadAsync(
    this Action<DataReceivedEventHandler> addHandler,
    Action<DataReceivedEventHandler> removeHandler,
    TextWriter textWriter,
    CancellationToken cancellationToken = default(CancellationToken))
    var taskCompletionSource = new TaskCompletionSource<object>();

    DataReceivedEventHandler handler = null;
    handler = new DataReceivedEventHandler(
        (sender, e) =>
            if (e.Data == null)


    if (cancellationToken != default(CancellationToken))
            () =>

    return taskCompletionSource.Task;

.net Core 2.0 - Package was restored using .NetFramework 4.6.1 instead of target framework .netCore 2.0. The package may not be fully compatible

The package is not fully compatible with dotnetcore 2.0 for now.

eg, for 'Microsoft.AspNet.WebApi.Client' it maybe supported in version (5.2.4). See Consume new Microsoft.AspNet.WebApi.Client.5.2.4 package for details.

You could try the standard Client package as Federico mentioned.

If that still not work, then as a workaround you can only create a Console App (.Net Framework) instead of the .net core 2.0 console app.

Reference this thread: Microsoft.AspNet.WebApi.Client supported in .NET Core or not?

Python BeautifulSoup extract text between element

soup = BeautifulSoup(html)
for hit in soup.findAll(attrs={'class' : 'MYCLASS'}):
  hit = hit.text.strip()
  print hit

This will print: THIS IS MY TEXT Try this..

How to style a select tag's option element?

I actually discovered something recently that seems to work for styling individual <option></option> elements within Chrome, Firefox, and IE using pure CSS.

Maybe, try the following:


    <option value="blank">Blank</option>
    <option class="white" value="white">White</option>
    <option class="red" value="red">Red</option>
    <option class="blue" value="blue">Blue</option>


select {
    color: #FFF;

select * {

select *.red { /* This, miraculously, styles the '<option class="red"></option>' elements. */

select *.white {

select *.blue {

Strange what throwing caution to the wind does. It doesn't seem to support the :active :hover :focus :link :visited :after :before, though.

Example on JSFiddle:

How can I disable the UITableView selection?

To disable the highlighting of the UItableviewcell

cell.selectionStyle = UITableViewCellSelectionStyleNone;

And should not allow the user to interact with the cell.

cell.userInteractionEnabled = NO;

How to check if a variable is an integer in JavaScript?

For positive integer values without separators:

return ( data !== '' && data === data.replace(/\D/, '') );

Tests 1. if not empty and 2. if value is equal to the result of a replace of a non-digit char in its value.

Can I make a phone call from HTML on Android?

Generally on Android, if you simply display the phone number, and the user taps on it, it will pull it up in the dialer. So, you could simply do

For more information, call us at <b>416-555-1234</b>

When the user taps on the bold part, since it's formatted like a phone number, the dialer will pop up, and show 4165551234 in the phone number field. The user then just has to hit the call button.

You might be able to do

For more information, call us at <a href='tel:416-555-1234'>416-555-1234</a>

to cover both devices, but I'm not sure how well this would work. I'll give it a try shortly and let you know.

EDIT: I just gave this a try on my HTC Magic running a rooted Rogers 1.5 with SenseUI:

For more information, call us at <a href='tel:416-555-1234'>416-555-1234</a><br />
<br />
Call at <a href='tel:416-555-1234'>our number</a>
<br />
<br />
<a href='416-555-1234'>Blah</a>
<br />
<br />
For more info, call <b>416-555-1234</b>

The first one, surrounding with the link and printing the phone number, worked perfectly. Pulled up the dialer with the hyphens and all. The second, saying our number with the link, worked exactly the same. This means that using <a href='tel:xxx-xxx-xxxx'> should work across the board, but I wouldn't suggest taking my one test as conclusive.

Linking straight to the number did the expected: Tried to pull up the nonexistent file from the server.

The last one did as I mentioned above, and pulled up the dialer, but without the nice formatting hyphens.

How do I send an HTML Form in an Email .. not just MAILTO

<FORM Action="mailto:xyz?Subject=Test_Post" METHOD="POST">
    mailto: protocol test:
    <INPUT name="Subject" value="Test Subject">
    <TEXTAREA name="Body">
    <INPUT type="submit" value="Submit"> 

Python and SQLite: insert into table

Not a direct answer, but here is a function to insert a row with column-value pairs into sqlite table:

def sqlite_insert(conn, table, row):
    cols = ', '.join('"{}"'.format(col) for col in row.keys())
    vals = ', '.join(':{}'.format(col) for col in row.keys())
    sql = 'INSERT INTO "{0}" ({1}) VALUES ({2})'.format(table, cols, vals)
    conn.cursor().execute(sql, row)

Example of use:

sqlite_insert(conn, 'stocks', {
        'created_at': '2016-04-17',
        'type': 'BUY',
        'amount': 500,
        'price': 45.00})

Note, that table name and column names should be validated beforehand.

How to obfuscate Python code effectively?

The best way to do this is to first generate a .c file, and then compile it with tcc to a .pyd file
Note: Windows-only


  1. tcc
  2. pyobfuscate
  3. Cython


sudo pip install -U cython

To obfuscate your .py file: >

To generate a .c file,

  1. Add an init<filename>() function to your .py file Optional

  2. cython --embed

  3. cp Python.h tcc\include

  4. tcc file.c -o file.pyd -shared -I\path\to\Python\include -L\path\to\Python\lib

  5. import .pyd file into app.exe

Set form backcolor to custom color

With Winforms you can use Form.BackColor to do this.
From within the Form's code:

BackColor = Color.LightPink;

If you mean a WPF Window you can use the Background property.
From within the Window's code:

Background = Brushes.LightPink;

Rolling back bad changes with svn in Eclipse

If you want to do 1 file at a time you can go to the History view for the file assuming you have an Eclipse SVN plugin installed. "Team->Show History"

In the History view, find the last good version of that file, right click and choose "Get Contents". This will replace your current version with that version's contents. Then you can commit the changes when you've fixed it all up.

How to copy files between two nodes using ansible

If you need to sync files between two remote nodes via ansible you can use this:

- name: synchronize between nodes
    RSYNC_PASSWORD: "{{ input_user_password_if_needed }}"
    src: rsync://user@remote_server:/module/
    dest: /destination/directory/
    // if needed
       - "--include=what_needed"
       - "--exclude=**/**"
    mode: pull
    delegate_to: "{{ inventory_hostname }}"

when on remote_server you need to startup rsync with daemon mode. Simple example:

pid file = /var/run/
lock file = /var/run/rsync.lock
log file = /var/log/rsync.log
port = port

path = /path/to/needed/directory/
uid = nobody
gid = nobody
read only = yes
list = yes
auth users = user
secrets file = /path/to/secret/file

openssl s_client using a proxy

Even with openssl v1.1.0 I had some problems passing our proxy, e.g. s_client: HTTP CONNECT failed: 400 Bad Request That forced me to write a minimal Java-class to show the SSL-Handshake

    public static void main(String[] args) throws IOException, URISyntaxException {
    HttpHost proxy = new HttpHost("", 8080);
    DefaultProxyRoutePlanner routePlanner = new DefaultProxyRoutePlanner(proxy);
    CloseableHttpClient httpclient = HttpClients.custom()
    URI uri = new URIBuilder()
    HttpGet httpget = new HttpGet(uri);

With following dependency:


you can run it with Java SSL Logging turned on

This should produce nice output like

trustStore provider is :
init truststore
adding as trusted cert:
  Subject: CN=Equifax Secure Global eBusiness CA-1, O=Equifax Secure Inc., C=US
  Issuer:  CN=Equifax Secure Global eBusiness CA-1, O=Equifax Secure Inc., C=US
  Algorithm: RSA; Serial number: 0xc3517
  Valid from Mon Jun 21 06:00:00 CEST 1999 until Mon Jun 22 06:00:00 CEST 2020

adding as trusted cert:
  Subject: CN=SecureTrust CA, O=SecureTrust Corporation, C=US
  Issuer:  CN=SecureTrust CA, O=SecureTrust Corporation, C=US

How to do a newline in output

Use "\n" instead of '\n'

How to change legend size with matplotlib.pyplot

you can reduce the legend size setting:

plt.legend(labelspacing=y, handletextpad=x,fontsize)  

labelspacing is the vertical space between each label.

handletextpad is the distance between the actual legend and your label.

And fontsize is self-explanatory

Dynamically change bootstrap progress bar value when checkboxes checked

Bootstrap 4 progress bar

<div class="progress">
<div class="progress-bar" role="progressbar" style="" aria-valuenow="" aria-valuemin="0" aria-valuemax="100"></div>


change progress bar on next/previous page actions

var count = Number(document.getElementById('count').innerHTML); //set this on page load in a hidden field after an ajax call
var total = document.getElementById('total').innerHTML; //set this on initial page load
var pcg = Math.floor(count/total*100);        

How to make a new line or tab in <string> XML (eclipse/android)?

  • Include this line in your layout xmlns:tools=""
  • Now , use \n for new line and \t for space like tab.
  • Example :

    for \n : android:text="Welcome back ! \nPlease login to your account agilanbu"

    for \t : android:text="Welcome back ! \tPlease login to your account agilanbu"

How do I improve ASP.NET MVC application performance?

In your clamour to optimize the client side, don't forget about the database layer. We had an application that went from 5 seconds to load up to 50 seconds overnight.

On inspection, we'd made a whole bunch of schema changes. Once we refreshed the statistics, it suddenly became as responsive as before.

HTML table needs spacing between columns, not rows

<table cellpadding="pixels"cellspacing="pixels"></table>
<td align="position"valign="position"></td>

cellpadding="length in pixels" ~ The cellpadding attribute, used in the <table> tag, specifies how much blank space to display in between the content of each table cell and its respective border. The value is defined as a length in pixels. Hence, a cellpadding="10" attribute-value pair will display 10 pixels of blank space on all four sides of the content of each cell in that table.

cellspacing="length in pixels" ~ The cellspacing attribute, also used in the <table> tag, defines how much blank space to display in between adjacent table cells and in between table cells and the table border. The value is defined as a length in pixels. Hence, a cellspacing="10" attribute-value pair will horizontally and vertically separate all adjacent cells in the respective table by a length of 10 pixels. It will also offset all cells from the table's frame on all four sides by a length of 10 pixels.

Get the value of input text when enter key pressed

Something like this (not tested, but should work)

Pass this as parameter in Html:

<input type="text" placeholder="some text" class="search" onkeydown="search(this)"/>

And alert the value of the parameter passed into the search function:

function search(e){

How to obtain the query string from the current URL with JavaScript?

Try this one

 * Get the value of a querystring
 * @param  {String} field The field to get the value of
 * @param  {String} url   The URL to get the value from (optional)
 * @return {String}       The field value
var getQueryString = function ( field, url ) {
    var href = url ? url : window.location.href;
    var reg = new RegExp( '[?&]' + field + '=([^&#]*)', 'i' );
    var string = reg.exec(href);
    return string ? string[1] : null;

Let’s say your URL is You want to get the value of this, that, and another.

var thisOne = getQueryString('this'); // returns 'chicken'
var thatOne = getQueryString('that'); // returns 'sandwich'
var anotherOne = getQueryString('another'); // returns null

If you want to use a URL other than the one in the window, you can pass one in as a second argument.

var yetAnotherOne = getQueryString('example', ''); // returns 'something'


What is the difference between a pandas Series and a single-column DataFrame?

Import cars data

import pandas as pd

cars = pd.read_csv('cars.csv', index_col = 0)

Here is how the cars.csv file looks.

Print out drives_right column as Series:


    US      True
    AUS    False
    JAP    False
    IN     False
    RU      True
    MOR     True
    EG      True
    Name: drives_right, dtype: bool

The single bracket version gives a Pandas Series, the double bracket version gives a Pandas DataFrame.

Print out drives_right column as DataFrame


    US           True
    AUS         False
    JAP         False
    IN          False
    RU           True
    MOR          True
    EG           True

Adding a Series to another Series creates a DataFrame.

bash assign default value

The default value parameter expansion is often useful in build scripts like the example one below. If the user just calls the script as-is, perl will not be built in. The user has to explicitly set WITH_PERL to a value other than "no" to have it built in.

$ cat


if [[ "$WITH_PERL" != no ]]; then
    echo "building with perl"
    # ./configure --enable=perl
    echo "not building with perl"
    # ./configure

Build without Perl

$ ./
not building with perl

Build with Perl

$ WITH_PERL=yes ./
building with perl

Getting a HeadlessException: No X11 DISPLAY variable was set

I think you are trying to run some utility or shell script from UNIX\LINUX which has some GUI. Anyways

SOLUTION: dude all you need is an XServer & X11 forwarding enabled. I use XMing (XServer). You are already enabling X11 forwarding. Just Install it(XMing) and keep it running when you create the session with PuTTY.

Save Javascript objects in sessionStorage

This is a dynamic solution which works with all value types including objects :

class Session extends Map {
  set(id, value) {
    if (typeof value === 'object') value = JSON.stringify(value);
    sessionStorage.setItem(id, value);

  get(id) {
    const value = sessionStorage.getItem(id);
    try {
      return JSON.parse(value);
    } catch (e) {
      return value;

Then :

const session = new Session();

session.set('name', {first: 'Ahmed', last : 'Toumi'});

Pandas timeseries plot setting x-axis major and minor ticks and labels

Both pandas and matplotlib.dates use matplotlib.units for locating the ticks.

But while matplotlib.dates has convenient ways to set the ticks manually, pandas seems to have the focus on auto formatting so far (you can have a look at the code for date conversion and formatting in pandas).

So for the moment it seems more reasonable to use matplotlib.dates (as mentioned by @BrenBarn in his comment).

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt 
import matplotlib.dates as dates

idx = pd.date_range('2011-05-01', '2011-07-01')
s = pd.Series(np.random.randn(len(idx)), index=idx)

fig, ax = plt.subplots()
ax.plot_date(idx.to_pydatetime(), s, 'v-')
ax.xaxis.grid(True, which="minor")


(my locale is German, so that Tuesday [Tue] becomes Dienstag [Di])

How to sleep the thread in node.js without affecting other threads?

Please consider the deasync module, personally I don't like the Promise way to make all functions async, and keyword async/await anythere. And I think the official node.js should consider to expose the event loop API, this will solve the callback hell simply. Node.js is a framework not a language.

var node = require("deasync");
node.loop = node.runLoopOnce;

var done = 0;
// async call here
db.query("select * from ticket", (error, results, fields)=>{
    done = 1;

while (!done)

// Now, here you go

Set Locale programmatically

As of 2020 language management become easy! All you have to do is:

  1. Call to Activity.applyOverrideConfiguration
  2. And call to Locale.setDefault

You must call those from the activity constructor since you can call to applyOverrideConfiguration only once, and the system calls it pretty early.

And watch out from app-bundles, Google will split your APK by language resources automatically when using app-bundles. Check out the new API and the workaround here.

I created a helper class to help you with it. In my implementation is the application context. Also, I need to access resources from the app context so I use the Res class for it, this one is optional, but I provide its code as well.


public BaseActivity(){

public void changeLanguage(Local local){
    // you must recreat your activity after you call this
    LanguageUtillity.setDefaultLanguage(local, this);

Source code

public class LanguageUtility {

    private static Configuration configuration;

    public static void setDefaultLanguage(Locale locale, Context context) {

        context.getSharedPreferences("LocaleSettings", Context.MODE_PRIVATE)
                .putString("language", locale.getLanguage())
                .putString("country", locale.getCountry())
                .putString("variant", locale.getVariant())

        configuration = createConfiguration(context);

     * Used to update your app context in case you cache it.
    public static Context createConfigurationContext(Context context) {
        return context.createConfigurationContext(getConfiguration(context));

    public static void init(Activity activity) {
        // you can't access sharedPrefferences from activity constructor 
        // with activity context, so I used the app context.

    private static Configuration getConfiguration(Context context) {
        if (configuration == null) {
            configuration = createConfiguration(context);
        return configuration;

    private static Configuration createConfiguration(Context context) {
        Locale locale = getLocale(context);
        Configuration configuration = new Configuration();
        LanguageUtility.configuration = configuration;
        return configuration;

    private static Locale getLocale(Context context) {
        Locale aDefault = Locale.getDefault();
        SharedPreferences preferences =
                context.getSharedPreferences("LocaleSettings", Context.MODE_PRIVATE);
        String language = preferences.getString("language", aDefault.getLanguage());
        String country = preferences.getString("country", aDefault.getCountry());
        String variant = preferences.getString("variant", aDefault.getVariant());
        return new Locale(language, country, variant);

An optional Res class.

public class Res {

    public static Context appLocalContext = LanguageUtility.createConfigurationContext(;

    public static void updateContext() {
        appLocalContext = LanguageUtility.createConfigurationContext(;

    public static String getString(@StringRes int id, Object... formatArgs) {
        return appLocalContext.getResources().getString(id, formatArgs);

    public static int getColor(@ColorRes int id) {

jQuery iframe load() event?

If possible, you'd be better off handling the load event within the iframe's document and calling out to a function in the containing document. This has the advantage of working in all browsers and only running once.

In the main document:

function iframeLoaded() {
    alert("Iframe loaded!");

In the iframe document:

window.onload = function() {

How to get all columns' names for all the tables in MySQL?

I wrote this silly thing a long time ago and still actually use it now and then:

Basically, it does a "SHOW TABLES", then a "DESCRIBE " on each table, then spits it out as markdown.

Just edit below the "if name" and go. You'll need to have pymysql installed.

CSS: transition opacity on mouse-out?

I managed to find a solution using css/jQuery that I'm comfortable with. The original issue: I had to force the visibility to be shown while animating as I have elements hanging outside the area. Doing so, made large blocks of text now hang outside the content area during animation as well.

The solution was to start the main text elements with an opacity of 0 and use addClass to inject and transition to an opacity of 1. Then removeClass when clicked on again.

I'm sure there's an all jQquery way to do this. I'm just not the guy to do it. :)

So in it's most basic form...


Thanks for the help everyone.

How do I check if string contains substring?

You could use search or match for this. 'Yes' )

will return the position of the match, or -1 if it isn't found.

Retrofit 2 - Dynamic URL

As of Retrofit 2.0.0-beta2, if you have a service responding JSON from this URL : http://myhost/mypath

The following is not working :

public interface ClientService {
    Call<List<Client>> getClientList();

Retrofit retrofit = new Retrofit.Builder()

ClientService service = retrofit.create(ClientService.class);

Response<List<Client>> response = service.getClientList().execute();

But this is ok :

public interface ClientService {
    Call<List<Client>> getClientList(@Url String anEmptyString);

Retrofit retrofit = new Retrofit.Builder()

ClientService service = retrofit.create(ClientService.class);

Response<List<Client>> response = service.getClientList("").execute();

How to hide output of subprocess in Python 2.7

As of Python3 you no longer need to open devnull and can call subprocess.DEVNULL.

Your code would be updated as such:

import subprocess
text = 'Hello World.'
print(text)['espeak', text], stderr=subprocess.DEVNULL)

Why does "pip install" inside Python raise a SyntaxError?

Try upgrade pip with the below command and retry

python -m pip install -U pip

Didn't find class ""?

This is due to MultiDex.

Steps to solve:

  1. In gradle->dependencies->(compile'') Add this in dependencies

  2. In your project application class extends MultiDexApplication like this (public class MyApplication extends MultiDexApplication)

  3. Run and check

React Native Change Default iOS Simulator Device

You can also use npm for this by adding an entry to the scripts element of your package.json file. E.g.

"launch-ios": "react-native run-ios --simulator \"iPad Air 2\""

Then to use this: npm run launch-ios

See what's in a stash without applying it

From the man git-stash page:

The modifications stashed away by this command can be listed with git stash list, inspected with git stash show

show [<stash>]
       Show the changes recorded in the stash as a diff between the stashed state and
       its original parent. When no <stash> is given, shows the latest one. By default,
       the command shows the diffstat, but it will accept any format known to git diff
       (e.g., git stash show -p stash@{1} to view the second most recent stash in patch

To list the stashed modifications

git stash list

To show files changed in the last stash

git stash show

So, to view the content of the most recent stash, run

git stash show -p

To view the content of an arbitrary stash, run something like

git stash show -p stash@{1}

Easy way to make a confirmation dialog in Angular?

You could use sweetalert:

npm install sweetalert --save

Then, simply import it into your application:

import swal from 'sweetalert';

If you pass two arguments, the first one will be the modal's title, and the second one its text.

swal("Here's the title!", "...and here's the text!");

How to align an input tag to the center without specifying the width?

To have text-align:center work you need to add that style to the #siteInfo div or wrap the input in a paragraph and add text-align:center to the paragraph.

An Iframe I need to refresh every 30 seconds (but not the whole page)

add "id='myiframe'" to the iframe, then use this script :


function f1()
 var x=document.getElementById("myiframe");



android edittext onchange listener

I have done it using AutotextView:

AutotextView textView = (AutotextView) findViewById(;
textView.addTextChangedListener(new TextWatcher() {

    public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
        seq = cs;

    public void beforeTextChanged(CharSequence s, int arg1, int arg2, int arg3) {


    public void afterTextChanged(Editable arg0) {
        new SearchTask().execute(seq.toString().trim());


Python: Removing list element while iterating over list

You can still use filter, moving to an outside function the element modification (iterating just once)

def do_the_magic(x):
    return check(x)

# you can get a different filtered list

# or have it modified in place (as suggested by Steven Rumbalski, see comment)
yourList[:] = itertools.ifilter(do_the_magic, yourList)

print memory address of Python variable

According to the manual, in CPython id() is the actual memory address of the variable. If you want it in hex format, call hex() on it.

x = 5
print hex(id(x))

this will print the memory address of x.

onKeyDown event not working on divs in React

You're missing the binding of the method in the constructor. This is how React suggests that you do it:

class Whatever {
  constructor() {
    this.onKeyPressed = this.onKeyPressed.bind(this);

  onKeyPressed(e) {
    // your code ...

  render() {
    return (<div onKeyDown={this.onKeyPressed} />);

There are other ways of doing this, but this will be the most efficient at runtime.

How to "grep" out specific line ranges of a file

If you want lines instead of line ranges, you can do it with perl: eg. if you want to get line 1, 3 and 5 from a file, say /etc/passwd:

perl -e 'while(<>){if(++$l~~[1,3,5]){print}}' < /etc/passwd

show loading icon until the page is load?


    <div id="load"></div>
    <div id="contents">


document.onreadystatechange = function () {
  var state = document.readyState
  if (state == 'interactive') {
  } else if (state == 'complete') {


    background:url("") no-repeat center center rgba(0,0,0,0.25)

you wont see any loading gif if your page is loaded fast, so use this code on a page with high loading time, and i also recommend to put your js on the bottom of the page.

DEMO - with timeout(only for demo) - no timeout(use this for actual page)


Is there a developers api for

Craigslist does have a "bulk posting interface" which allows for multiple posts to happen at once through HTTPS POST. See:

How to concatenate strings in windows batch file for loop?

Try this, with strings:

set "var=string1string2string3"

and with string variables:

set "var=%string1%%string2%%string3%"

How to extract numbers from string in c?

Make a state machine that operates on one basic principle: is the current character a number.

  • When transitioning from non-digit to digit, you initialize your current_number := number.
  • when transitioning from digit to digit, you "shift" the new digit in:
    current_number := current_number * 10 + number;
  • when transitioning from digit to non-digit, you output the current_number
  • when from non-digit to non-digit, you do nothing.

Optimizations are possible.

Convert List(of object) to List(of string)

If you want more control over how the conversion takes place, you can use ConvertAll:

var stringList = myList.ConvertAll(obj => obj.SomeToStringMethod());

How can I run code on a background thread on Android?

IF you need to:

  1. execute code on a background Thread

  2. execute code that DOES NOT touch/update the UI

  3. execute (short) code which will take at most a few seconds to complete

THEN use the following clean and efficient pattern which uses AsyncTask:

AsyncTask.execute(new Runnable() {
   public void run() {
      //TODO your background code

Oracle - How to create a materialized view with FAST REFRESH and JOINS

Have you tried it without the ANSI join ?


Python: Remove division decimal

def division(a, b):
    return a / b if a % b else a // b

Remove trailing comma from comma-separated string

i am sharing code form my project using regular expression you can do this...

String ChildBelowList = "";

    if (!Childbelow.isEmpty()) {
        for (int iCB = 0; iCB < Childbelow.size(); iCB++) {

            ChildBelowList = ChildBelowList += Childbelow.get(iCB) + ",";

        ChildBelowList = ChildBelowList.replaceAll("(^(\\s*?\\,+)+\\s?)|(^\\s+)|(\\s+$)|((\\s*?\\,+)+\\s?$)", "");


    } else {

Angular Material: mat-select not selecting default

You should be binding it as [value] in the mat-option as below,

<mat-select placeholder="Panel color" [(value)]="selected2">
  <mat-option *ngFor="let option of options2" [value]="">
    {{ }}


How to detect input type=file "change" for the same file?

By default, the value property of input element cleared after selection of files if the input have multiple attributes. If you do not clean this property then "change" event will not be fired if you select the same file. You can manage this behavior using multiple attribute.

<!-- will be cleared -->
<input type="file" onchange="yourFunction()" multiple/>
<!-- won't be cleared -->
<input type="file" onchange="yourFunction()"/>


Go: panic: runtime error: invalid memory address or nil pointer dereference

According to the docs for func (*Client) Do:

"An error is returned if caused by client policy (such as CheckRedirect), or if there was an HTTP protocol error. A non-2xx response doesn't cause an error.

When err is nil, resp always contains a non-nil resp.Body."

Then looking at this code:

res, err := client.Do(req)
defer res.Body.Close()

if err != nil {
    return nil, err

I'm guessing that err is not nil. You're accessing the .Close() method on res.Body before you check for the err.

The defer only defers the function call. The field and method are accessed immediately.

So instead, try checking the error immediately.

res, err := client.Do(req)

if err != nil {
    return nil, err
defer res.Body.Close()

VMware Workstation and Device/Credential Guard are not compatible

the simplest solution for this issue is to download the "Device Guard and Credential Guard hardware readiness tool" to correct the incompatibility :

How to completely uninstall Android Studio on Mac?

Some of the files individually listed by Simon would also be found with something like the following command, but with some additional assurance about thoroughness, and without the recklessness of using rm -rf with wildcards:

find ~ \
  -path ~/Library/Caches/Metadata/Safari -prune -o \
  -iname \*android\*studio\* -print -prune

Also don't forget about the SDK, which is now separate from the application, and ~/.gradle/ (see vijay's answer).

Embed Google Map code in HTML with marker

I would suggest this way, one line iframe. no javascript needed at all. In query ?q=,

<iframe src=",77.627108&z=15&output=embed"></iframe>

How can I add C++11 support to Code::Blocks compiler?

  1. Go to Toolbar -> Settings -> Compiler
  2. In the Selected compiler drop-down menu, make sure GNU GCC Compiler is selected
  3. Below that, select the compiler settings tab and then the compiler flags tab underneath
  4. In the list below, make sure the box for "Have g++ follow the C++11 ISO C++ language standard [-std=c++11]" is checked
  5. Click OK to save

How to set column header text for specific column in Datagridview C#




Unable to load script from assets on windows

I encountered this issue not with a real device, but with an emulator. I fixed it by running react-native start in the terminal before trying to run the code with android studio. I never encountered this issue when running react-native run-android in the terminal.

How to set an environment variable in a running docker container

If you are running the container as a service using docker swarm, you can do:

docker service update --env-add <you environment variable> <service_name>

Also remove using --env-rm

To make sure it's addedd as you wanted, just run: docker exec -it <container id> env

how to Call super constructor in Lombok

As an option you can use com.fasterxml.jackson.databind.ObjectMapper to initialize a child class from parent

public class A {
    int x;
    int y;

public class B extends A {
    int z;

ObjectMapper MAPPER = new ObjectMapper(); //it's configurable
MAPPER.configure( DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false );
MAPPER.configure( SerializationFeature.FAIL_ON_EMPTY_BEANS, false );

//Then wherever you need to initialize child from parent:
A parent = new A(x, y);
B child = MAPPER.convertValue( parent, B.class);

You can still use any lombok annotations on A and B if you need.

Disable arrow key scrolling in users browser


Simply prevent the default browser action:

window.addEventListener("keydown", function(e) {
    // space and arrow keys
    if([32, 37, 38, 39, 40].indexOf(e.code) > -1) {
}, false);

If you need to support Internet Explorer or other older browsers, use e.keyCode instead of e.code, but keep in mind that keyCode is deprecated.

Original answer

I used the following function in my own game:

var keys = {};
        keys[e.code] = true;
            case 37: case 39: case 38:  case 40: // Arrow keys
            case 32: e.preventDefault(); break; // Space
            default: break; // do not block other keys
        keys[e.code] = false;

The magic happens in e.preventDefault();. This will block the default action of the event, in this case moving the viewpoint of the browser.

If you don't need the current button states you can simply drop keys and just discard the default action on the arrow keys:

var arrow_keys_handler = function(e) {
        case 37: case 39: case 38:  case 40: // Arrow keys
        case 32: e.preventDefault(); break; // Space
        default: break; // do not block other keys
window.addEventListener("keydown", arrow_keys_handler, false);

Note that this approach also enables you to remove the event handler later if you need to re-enable arrow key scrolling:

window.removeEventListener("keydown", arrow_keys_handler, false);


Remove HTML Tags in Javascript with Regex

my simple JavaScript library called FuncJS has a function called "strip_tags()" which does the task for you — without requiring you to enter any regular expressions.

For example, say that you want to remove tags from a sentence - with this function, you can do it simply like this:

strip_tags("This string <em>contains</em> <strong>a lot</strong> of tags!");

This will produce "This string contains a lot of tags!".

For a better understanding, please do read the documentation at GitHub FuncJS.

Additionally, if you'd like, please provide some feedback through the form. It would be very helpful to me!

set height of imageview as matchparent programmatically

For Kotlin Users

val params = mImageView?.layoutParams as FrameLayout.LayoutParams
params.width = FrameLayout.LayoutParams.MATCH_PARENT
params.height = FrameLayout.LayoutParams.MATCH_PARENT
mImageView?.layoutParams = params

Here I used FrameLayout.LayoutParams since my views( ImageView) parent is FrameLayout

How do you log content of a JSON object in Node.js?


Run: node app.js > output.txt


If you have a different flavour of the app, try uninstalling that first. This helped me when I had the same issue.

How to connect to SQL Server from another computer?

I'll edit my previous answer based on further info supplied. You can clearely ping the remote computer as you can use terminal services.

I've a feeling that port 1433 is being blocked by a firewall, hence your trouble. See TCP Ports Needed for Communication to SQL Server Through a Firewall by Microsoft.

Try using this application to ping your servers ip address and port 1433.

tcping your.server.ip.address 1433

And see if you get a "Port is open" response from tcping.

Ok, next to try is to check SQL Server. RDP onto the SQL Server computer. Start SSMS. Connect to the database. In object explorer (usually docked on the left) right click on the server and click properties.

alt text

Goto the Connections settings and make sure "Allow remote connections to this server" is ticket.

alt text

Send JavaScript variable to PHP variable

It depends on the way your page behaves. If you want this to happens asynchronously, you have to use AJAX. Try out "jQuery post()" on Google to find some tuts.

In other case, if this will happen when a user submits a form, you can send the variable in an hidden field or append ?variableName=someValue" to then end of the URL you are opening. :


This way, from PHP you can access this value as:

$phpVariableName = $_POST["variableName"];

for forms using POST method or:

$phpVariableName = $_GET["variableName"];

for forms using GET method or the append to url method I've mentioned above (querystring).

How to pass payload via JSON file for curl?

curl sends POST requests with the default content type of application/x-www-form-urlencoded. If you want to send a JSON request, you will have to specify the correct content type header:

$ curl -vX POST http://server/api/v1/places.json -d @testplace.json \
--header "Content-Type: application/json"

But that will only work if the server accepts json input. The .json at the end of the url may only indicate that the output is json, it doesn't necessarily mean that it also will handle json input. The API documentation should give you a hint on whether it does or not.

The reason you get a 401 and not some other error is probably because the server can't extract the auth_token from your request.

how to generate web service out of wsdl

How about using the wsdl /server or wsdl /serverinterface switches? As far as I understand the wsdl.exe command line properties, that's what you're looking for.



Server switch has been deprecated. Please use /serverInterface instead.
Generate an abstract class for an xml web service implementation using
ASP.NET based on the contracts. The default is to generate client proxy

On the other hand: why do you want to create obsolete technology solutions? Why not create this web service as a WCF service. That's the current and more modern, much more flexible way to do this!



When I use wsdl /server on a WSDL file, I get this file created:

public abstract partial class OneCrmServiceType : System.Web.Services.WebService 
    /// <remarks/>
    public abstract void OrderCreated(......);

This is basically almost exactly the same code that gets generated when you add an ASMX file to your solution (in the code behind file - "yourservice.asmx.cs"). I don't think you can get any closer to creating an ASMX file from a WSDL file.

You can always add the "yourservice.asmx" manually - it doesn't really contain much:

<%@ WebService Language="C#" CodeBehind="YourService.asmx.cs" 
      Class="YourServiceNamespace.YourServiceClass" %>

How to encrypt String in Java

You can use Jasypt

With Jasypt, encrypting and checking a password can be as simple as...

StrongTextEncryptor textEncryptor = new StrongTextEncryptor();


String myEncryptedText = textEncryptor.encrypt(myText);


String plainText = textEncryptor.decrypt(myEncryptedText);


compile group: 'org.jasypt', name: 'jasypt', version: '1.9.2'


Jasypt provides you with easy unidirectional (digest) and bidirectional encryption techniques.

Open API for use with any JCE provider, and not only the default Java VM one. Jasypt can be easily used with well-known providers like Bouncy Castle. Learn more.

Higher security for your users' passwords. Learn more.

Binary encryption support. Jasypt allows the digest and encryption of binaries (byte arrays). Encrypt your objects or files when needed (for being sent over the net, for example).

Number encryption support. Besides texts and binaries, it allows the digest and encryption of numeric values (BigInteger and BigDecimal, other numeric types are supported when encrypting for Hibernate persistence). Learn more.

Completely thread-safe.

Support for encryptor/digester pooling, in order to achieve high performance in multi-processor/multi-core systems.

Includes a lightweight ("lite") version of the library for better manageability in size-restrictive environments like mobile platforms.

Provides both easy, no-configuration encryption tools for users new to encryption, and also highly configurable standard encryption tools, for power-users.

Hibernate 3 and 4 optional integration for persisting fields of your mapped entities in an encrypted manner. Encryption of fields is defined in the Hibernate mapping files, and it remains transparent for the rest of the application (useful for sensitive personal data, databases with many read-enabled users...). Encrypt texts, binaries, numbers, booleans, dates... Learn more.

Seamlessly integrable into a Spring application, with specific integration features for Spring 2, Spring 3.0 and Spring 3.1. All the digesters and encryptors in jasypt are designed to be easily used (instantiated, dependency-injected...) from Spring. And, because of their being thread-safe, they can be used without synchronization worries in a singleton-oriented environment like Spring. Learn more: Spring 2, Spring 3.0, Spring 3.1.

Spring Security (formerly Acegi Security) optional integration for performing password encryption and matching tasks for the security framework, improving the security of your users' passwords by using safer password encryption mechanisms and providing you with a higher degree of configuration and control. Learn more.

Provides advanced functionality for encrypting all or part of an application's configuration files, including sensitive information like database passwords. Seamlessly integrate encrypted configuration into plain, Spring-based and/or Hibernate-enabled applications. Learn more.

Provides easy to use CLI (Command Line Interface) tools to allow developers initialise their encrypted data and include encryption/decryption/digest operations in maintenance tasks or scripts. Learn more.

Integrates into Apache Wicket, for more robust encryption of URLs in your secure applications.

Comprehensive guides and javadoc documentation, to allow developers to better understand what they are really doing to their data.

Robust charset support, designed to adequately encrypt and digest texts whichever the original charset is. Complete support for languages like Japanese, Korean, Arabic... with no encoding or platform issues.

Very high level of configuration capabilities: The developer can implement tricks like instructing an "encryptor" to ask a, for example, remote HTTPS server for the password to be used for encryption. It lets you meet your security needs.

SOAP-ERROR: Parsing WSDL: Couldn't load from - but works on WAMP

You cant blame code all the time sometime may be your url is wrong , double check urls

Unit Tests not discovered in Visual Studio 2017

Just had this problem with visual studio being unable to find my tests, couldn't see the button to run them besides the method, and they weren't picked up by running all tests in the project.

Turns out my test class wasn't public! Making it public allowed VS to discover the tests.

How do I generate a list with a specified increment step?

Executing seq(1, 10, 1) does what 1:10 does. You can change the last parameter of seq, i.e. by, to be the step of whatever size you like.

> #a vector of even numbers
> seq(0, 10, by=2) # Explicitly specifying "by" only to increase readability 
> [1]  0  2  4  6  8 10

Python: Ignore 'Incorrect padding' error when base64 decoding

In my case I faced that error while parsing an email. I got the attachment as base64 string and extract it via Eventually there was a strange additional substring at the end.



When I deleted --_=ic0008m4wtZ4TqBFd+sXC8-- and strip the string then parsing was fixed up.

So my advise is make sure that you are decoding a correct base64 string.

Java compile error: "reached end of file while parsing }"

You have to open and close your class with { ... } like:

public class mod_MyMod extends BaseMod
  public String Version()
    return "1.2_02";

  public void AddRecipes(CraftingManager recipes)
     recipes.addRecipe(new ItemStack(Item.diamond), new Object[] {
        "#", Character.valueOf('#'), Block.dirt });

How to hide first section header in UITableView (grouped style)

The answer was very funny for me and my team, and worked like a charm

  • In the Interface Builder, Just move the tableview under another view in the view hierarchy.


We observed that this happens only for the First View in the View Hierarchy, if this first view is a UITableView. So, all other similar UITableViews do not have this annoying section, except the first. We Tried moving the UITableView out of the first place in the view hierarchy, and everything was working as expected.

Case in Select Statement

I think these could be helpful for you .

Using a SELECT statement with a simple CASE expression

Within a SELECT statement, a simple CASE expression allows for only an equality check; no other comparisons are made. The following example uses the CASE expression to change the display of product line categories to make them more understandable.

USE AdventureWorks2012;
SELECT   ProductNumber, Category =
      CASE ProductLine
         WHEN 'R' THEN 'Road'
         WHEN 'M' THEN 'Mountain'
         WHEN 'T' THEN 'Touring'
         WHEN 'S' THEN 'Other sale items'
         ELSE 'Not for sale'
FROM Production.Product
ORDER BY ProductNumber;

Using a SELECT statement with a searched CASE expression

Within a SELECT statement, the searched CASE expression allows for values to be replaced in the result set based on comparison values. The following example displays the list price as a text comment based on the price range for a product.

USE AdventureWorks2012;
SELECT   ProductNumber, Name, "Price Range" = 
         WHEN ListPrice =  0 THEN 'Mfg item - not for resale'
         WHEN ListPrice < 50 THEN 'Under $50'
         WHEN ListPrice >= 50 and ListPrice < 250 THEN 'Under $250'
         WHEN ListPrice >= 250 and ListPrice < 1000 THEN 'Under $1000'
         ELSE 'Over $1000'
FROM Production.Product
ORDER BY ProductNumber ;

Using CASE in an ORDER BY clause

The following examples uses the CASE expression in an ORDER BY clause to determine the sort order of the rows based on a given column value. In the first example, the value in the SalariedFlag column of the HumanResources.Employee table is evaluated. Employees that have the SalariedFlag set to 1 are returned in order by the BusinessEntityID in descending order. Employees that have the SalariedFlag set to 0 are returned in order by the BusinessEntityID in ascending order. In the second example, the result set is ordered by the column TerritoryName when the column CountryRegionName is equal to 'United States' and by CountryRegionName for all other rows.

SELECT BusinessEntityID, SalariedFlag
FROM HumanResources.Employee
ORDER BY CASE SalariedFlag WHEN 1 THEN BusinessEntityID END DESC
        ,CASE WHEN SalariedFlag = 0 THEN BusinessEntityID END;

SELECT BusinessEntityID, LastName, TerritoryName, CountryRegionName
FROM Sales.vSalesPerson
ORDER BY CASE CountryRegionName WHEN 'United States' THEN TerritoryName
         ELSE CountryRegionName END;

Using CASE in an UPDATE statement

The following example uses the CASE expression in an UPDATE statement to determine the value that is set for the column VacationHours for employees with SalariedFlag set to 0. When subtracting 10 hours from VacationHours results in a negative value, VacationHours is increased by 40 hours; otherwise, VacationHours is increased by 20 hours. The OUTPUT clause is used to display the before and after vacation values.

USE AdventureWorks2012;
UPDATE HumanResources.Employee
SET VacationHours = 
    ( CASE
         WHEN ((VacationHours - 10.00) < 0) THEN VacationHours + 40
         ELSE (VacationHours + 20.00)
OUTPUT Deleted.BusinessEntityID, Deleted.VacationHours AS BeforeValue, 
       Inserted.VacationHours AS AfterValue
WHERE SalariedFlag = 0; 

Using CASE in a HAVING clause

The following example uses the CASE expression in a HAVING clause to restrict the rows returned by the SELECT statement. The statement returns the the maximum hourly rate for each job title in the HumanResources.Employee table. The HAVING clause restricts the titles to those that are held by men with a maximum pay rate greater than 40 dollars or women with a maximum pay rate greater than 42 dollars.

USE AdventureWorks2012;
SELECT JobTitle, MAX(ph1.Rate)AS MaximumRate
FROM HumanResources.Employee AS e
JOIN HumanResources.EmployeePayHistory AS ph1 ON e.BusinessEntityID = ph1.BusinessEntityID
        THEN ph1.Rate 
        ELSE NULL END) > 40.00
     OR MAX(CASE WHEN Gender  = 'F' 
        THEN ph1.Rate  
        ELSE NULL END) > 42.00)
ORDER BY MaximumRate DESC;

For more details description of these example visit the source.

Also visit here and here for some examples with great details.

How do I round a float upwards to the nearest int in C#?

Do I use one of these then cast to an Int?

Yes. There is no problem doing that. Decimals and doubles can represent integers exactly, so there will be no representation error. (You won't get a case, for instance, where Round returns 4.999... instead of 5.)

Count lines in large files

Your limiting speed factor is the I/O speed of your storage device, so changing between simple newlines/pattern counting programs won't help, because the execution speed difference between those programs are likely to be suppressed by the way slower disk/storage/whatever you have.

But if you have the same file copied across disks/devices, or the file is distributed among those disks, you can certainly perform the operation in parallel. I don't know specifically about this Hadoop, but assuming you can read a 10gb the file from 4 different locations, you can run 4 different line counting processes, each one in one part of the file, and sum their results up:

$ dd bs=4k count=655360 if=/path/to/copy/on/disk/1/file | wc -l &
$ dd bs=4k skip=655360 count=655360 if=/path/to/copy/on/disk/2/file | wc -l &
$ dd bs=4k skip=1310720 count=655360 if=/path/to/copy/on/disk/3/file | wc -l &
$ dd bs=4k skip=1966080 if=/path/to/copy/on/disk/4/file | wc -l &

Notice the & at each command line, so all will run in parallel; dd works like cat here, but allow us to specify how many bytes to read (count * bs bytes) and how many to skip at the beginning of the input (skip * bs bytes). It works in blocks, hence, the need to specify bs as the block size. In this example, I've partitioned the 10Gb file in 4 equal chunks of 4Kb * 655360 = 2684354560 bytes = 2.5GB, one given to each job, you may want to setup a script to do it for you based on the size of the file and the number of parallel jobs you will run. You need also to sum the result of the executions, what I haven't done for my lack of shell script ability.

If your filesystem is smart enough to split big file among many devices, like a RAID or a distributed filesystem or something, and automatically parallelize I/O requests that can be paralellized, you can do such a split, running many parallel jobs, but using the same file path, and you still may have some speed gain.

EDIT: Another idea that occurred to me is, if the lines inside the file have the same size, you can get the exact number of lines by dividing the size of the file by the size of the line, both in bytes. You can do it almost instantaneously in a single job. If you have the mean size and don't care exactly for the the line count, but want an estimation, you can do this same operation and get a satisfactory result much faster than the exact operation.

Scroll to bottom of div?

using jQuery animate:

  scrollTop: $('#DebugContainer')[0].scrollHeight
}, 800);

Is it possible to do a sparse checkout without checking out the whole repository first?

I found the answer I was looking for from the one-liner posted earlier by pavek (thanks!) so I wanted to provide a complete answer in a single reply that works on Linux (GIT 1.7.1):

1--> mkdir myrepo
2--> cd myrepo
3--> git init
4--> git config core.sparseCheckout true
5--> echo 'path/to/subdir/' > .git/info/sparse-checkout
6--> git remote add -f origin ssh://...
7--> git pull origin master

I changed the order of the commands a bit but that does not seem to have any impact. The key is the presence of the trailing slash "/" at the end of the path in step 5.

Maintain model of scope when changing between views in AngularJS

I had the same problem, This is what I did: I have a SPA with multiple views in the same page (without ajax), so this is the code of the module:

var app = angular.module('otisApp', ['chieffancypants.loadingBar', 'ngRoute']);

app.config(['$routeProvider', function($routeProvider){
    $routeProvider.when('/:page', {
        templateUrl: function(page){return + '.html';},

I have only one controller for all views, but, the problem is the same as the question, the controller always refresh data, in order to avoid this behavior I did what people suggest above and I created a service for that purpose, then pass it to the controller as follows:

app.factory('otisService', function($http){
    var service = {            

    return service;

app.controller('otisCtrl', ['$scope', '$window', 'otisService', '$routeParams',  
function($scope, $window, otisService, $routeParams){        
    $scope.message = "Hello from page: " + $;
    $scope.update = function(answer){

Now I can call the update function from any of my views, pass values and update my model, I haven't no needed to use html5 apis for persistence data (this is in my case, maybe in other cases would be necessary to use html5 apis like localstorage and other stuff).

Get $_POST from multiple checkboxes

you have to name your checkboxes accordingly:

<input type="checkbox" name="check_list[]" value="…" />

you can then access all checked checkboxes with

// loop over checked checkboxes
foreach($_POST['check_list'] as $checkbox) {
   // do something

ps. make sure to properly escape your output (htmlspecialchars())

Convert Little Endian to Big Endian

You could do this:

int x = 0x12345678;

x = ( x >> 24 ) | (( x << 8) & 0x00ff0000 )| ((x >> 8) & 0x0000ff00) | ( x << 24)  ; 

printf("value = %x", x);  // x will be printed as 0x78563412

Adding author name in Eclipse automatically to existing files

To old files I don't know how to do it... I think you will need a script to go thru all files and add the header.

To change the new ones you can do this.

Go to Eclipse menu bar

  1. Window menu.
  2. Preferences
  3. search for Templates
  4. go to Code templates
  5. click on +code
  6. Click on New Java files
  7. Click Edit
  8. add


And it's done every new File will have your name on it !

Cassandra cqlsh - connection refused

Got into this issue for [cqlsh 5.0.1 | Cassandra 3.11.4 | CQL spec 3.4.4 | Native protocol v4] had to set start_native_transport: true in cassandra.yaml file.

For verification,

  • try opening tailf /var/log/cassandra/system.log file in one-tab
  • update cassandra.yaml
  • restart cassandra sudo service cassandra restart

In logfile is shows.

INFO  [main] 2019-03-15 19:53:06,156 - Starting listening for CQL clients on / (unencrypted)...

Sending SMS from PHP

You need to subscribe to a SMS gateway. There are thousands of those (try searching with google) and they are usually not free. For example this one has support for PHP.

How do you create optional arguments in php?

The default value of the argument must be a constant expression. It can't be a variable or a function call.

If you need this functionality however:

function foo($foo, $bar = false)
        $bar = $foo;

Assuming $bar isn't expected to be a boolean of course.

JavaScript: replace last occurrence of text in a string

Couldn't you just reverse the string and replace only the first occurrence of the reversed search pattern? I'm thinking . . .

var list = ['one', 'two', 'three', 'four'];
var str = 'one two, one three, one four, one';
for ( var i = 0; i < list.length; i++)
     if (str.endsWith(list[i])
         var reversedHaystack = str.split('').reverse().join('');
         var reversedNeedle = list[i].split('').reverse().join('');

         reversedHaystack = reversedHaystack.replace(reversedNeedle, 'hsinif');
         str = reversedHaystack.split('').reverse().join('');

How do I add a placeholder on a CharField in Django?

You can use this code to add placeholder attr for every TextInput field in you form. Text for placeholders will be taken from model field labels.

class PlaceholderDemoForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super(PlaceholderDemoForm, self).__init__(*args, **kwargs)
        for field_name in self.fields:
            field = self.fields.get(field_name)  
            if field:
                if type(field.widget) in (forms.TextInput, forms.DateInput):
                    field.widget = forms.TextInput(attrs={'placeholder': field.label})

    class Meta:
        model = DemoModel

How to show x and y axes in a MATLAB graph?

Inspired by @Luisa's answer, I made a function, axes0

x = linspace(-2,2,101);

Example output for axes0

You can follow the link above to download the function and get more details on usage

How to preview a part of a large pandas DataFrame, in iPython notebook?

Here's a quick way to preview a large table without having it run too wide:

Display function:

# display large dataframes in an html iframe
def ldf_display(df, lines=500):
    txt = ("<iframe " +
           "srcdoc='" + df.head(lines).to_html() + "' " +
           "width=1000 height=500>" +

    return IPython.display.HTML(txt)

Now just run this in any cell:


This will convert the dataframe to html then display it in an iframe. The advantage is that you can control the output size and have easily accessible scroll bars.

Worked for my purposes, maybe it will help someone else.

TypeError: 'tuple' object does not support item assignment when swapping values

Evaluating "1,2,3" results in (1, 2, 3), a tuple. As you've discovered, tuples are immutable. Convert to a list before processing.

anaconda/conda - install a specific package version

If any of these characters, '>', '<', '|' or '*', are used, a single or double quotes must be used

conda install [-y] package">=version"
conda install [-y] package'>=low_version, <=high_version'
conda install [-y] "package>=low_version, <high_version"

conda install -y torchvision">=0.3.0"
conda install  openpyxl'>=2.4.10,<=2.6.0'
conda install "openpyxl>=2.4.10,<3.0.0"

where option -y, --yes Do not ask for confirmation.

Here is a summary:

Format         Sample Specification     Results
Exact          qtconsole==4.5.1         4.5.1
Fuzzy          qtconsole=4.5            4.5.0, 4.5.1, ..., etc.
>=, >, <, <=  "qtconsole>=4.5"          4.5.0 or higher
               qtconsole"<4.6"          less than 4.6.0

OR            "qtconsole=4.5.1|4.5.2"   4.5.1, 4.5.2
AND           "qtconsole>=4.3.1,<4.6"   4.3.1 or higher but less than 4.6.0

Potion of the above information credit to Conda Cheat Sheet

Tested on conda 4.7.12

How to draw border around a UILabel?

Swift version:

myLabel.layer.borderWidth = 0.5
myLabel.layer.borderColor = UIColor.greenColor().CGColor

For Swift 3:

myLabel.layer.borderWidth = 0.5
myLabel.layer.borderColor =

$_POST not working. "Notice: Undefined index: username..."

first of all,

be sure that there is a post

if(isset($_POST['username'])) { 
    // check if the username has been set

second, and most importantly, sanitize the data, meaning that

$query = "SELECT password FROM users WHERE username='".$_POST['username']."'";

is deadly dangerous, instead use

$query = "SELECT password FROM users WHERE username='".mysql_real_escape_string($_POST['username'])."'";

and please research the subject sql injection

What are some reasons for jquery .focus() not working?

You need to either put the code below the HTML or load if using the document load event:

<input type="text" id="goal-input" name="goal" />
<script type="text/javascript">


Switching divs doesn't trigger the document load event since everything already have been loaded. You need to focus it when you switch div:

if (goal) {
      step1.fadeOut('fast', function() {
          step2.fadeIn('fast', function() {  

Run a PHP file in a cron job using CPanel

It is actually very simple,

php -q /home/username/public_html/cron/cron.php

A JOIN With Additional Conditions Using Query Builder or Eloquent

If you have some params, you can do this.

    $results = DB::table('rooms')
    ->leftJoin('bookings', function($join) use ($param1, $param2)
        $join->on('', '=', 'bookings.room_type_id');

    ->where('bookings.room_type_id', '=', NULL)

and then return your query

return $results;

Using success/error/finally/catch with Promises in AngularJS

Promises are an abstraction over statements that allow us to express ourselves synchronously with asynchronous code. They represent a execution of a one time task.

They also provide exception handling, just like normal code, you can return from a promise or you can throw.

What you'd want in synchronous code is:

      var res = $http.getSync("url");
      res = someProcessingOf(res);
  } catch (e) {
      console.log("Got an error!",e);
      throw e; // rethrow to not marked as handled
  // do more stuff with res
} catch (e){
     // handle errors in processing or in error.

The promisified version is very similar:

   console.log("got an error in initial processing",e);
   throw e; // rethrow to not marked as handled, 
            // in $q it's better to `return $q.reject(e)` here
    // do more stuff
    // handle errors in processing or in error.

Rename a dictionary key

For a regular dict, you can use:

mydict[k_new] = mydict.pop(k_old)

This will move the item to the end of the dict, unless k_new was already existing in which case it will overwrite the value in-place.

For a Python 3.7+ dict where you additionally want to preserve the ordering, the simplest is to rebuild an entirely new instance. For example, renaming key 2 to 'two':

>>> d = {0:0, 1:1, 2:2, 3:3}
>>> {"two" if k == 2 else k:v for k,v in d.items()}
{0: 0, 1: 1, 'two': 2, 3: 3}

The same is true for an OrderedDict, where you can't use dict comprehension syntax, but you can use a generator expression:

OrderedDict((k_new if k == k_old else k, v) for k, v in od.items())

Modifying the key itself, as the question asks for, is impractical because keys are hashable which usually implies they're immutable and can't be modified.

setHintTextColor() in EditText

Use this to change the hint color. -


Solution for your problem -

editText.addTextChangedListener(new TextWatcher() {
    public void onTextChanged(CharSequence arg0, int arg1, int arg2,int arg3){
        //do something

    public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) {
        //do something

    public void afterTextChanged(Editable arg0) {
        if(arg0.toString().length() <= 0) //check if length is equal to zero

How to access route, post, get etc. parameters in Zend Framework 2

require_once 'lib/Zend/Loader/StandardAutoloader.php';
$loader = new Zend\Loader\StandardAutoloader(array('autoregister_zf' => true));

$loader->registerNamespace('Http\PhpEnvironment', 'lib/Zend/Http'); 

// Register with spl_autoload:

$a = new Zend\Http\PhpEnvironment\Request();
print_r($a->getQuery()->get()); exit;

How do I remove leading whitespace in Python?

The function strip will remove whitespace from the beginning and end of a string.

my_str = "   text "
my_str = my_str.strip()

will set my_str to "text".

Android Studio update -Error:Could not run build action using Gradle distribution

I had same issue. I have tried many things but nothing worked Until I try following:

  1. Close Android Studio
  2. Delete any directory matching gradle-[version]-all within C:\Users\<username>\.gradle\wrapper\dists\. If you encounter a "File in use" error (or similar), terminate any running Java executables.
  3. Open Android Studio as Administrator.
  4. Try to sync project files.
  5. If the above does not work, try restarting your computer and/or delete the project's .gradle directory.
  6. Open the problem project and trigger a Gradle sync.

Javascript Drag and drop for touch devices

You can use the Jquery UI for drag and drop with an additional library that translates mouse events into touch which is what you need, the library I recommend is, with this your drag and drop from Jquery UI should work on touch devises

or you can use this code which I am using, it also converts mouse events into touch and it works like magic.

function touchHandler(event) {
    var touch = event.changedTouches[0];

    var simulatedEvent = document.createEvent("MouseEvent");
        touchstart: "mousedown",
        touchmove: "mousemove",
        touchend: "mouseup"
    }[event.type], true, true, window, 1,
        touch.screenX, touch.screenY,
        touch.clientX, touch.clientY, false,
        false, false, false, 0, null);;

function init() {
    document.addEventListener("touchstart", touchHandler, true);
    document.addEventListener("touchmove", touchHandler, true);
    document.addEventListener("touchend", touchHandler, true);
    document.addEventListener("touchcancel", touchHandler, true);

And in your document.ready just call the init() function

code found from Here

Error: Unexpected value 'undefined' imported by the module

My problem was a misspelled component name inside the component.ts.

The import statement didn't show an error but the declaration did, which misled me.

How to install mod_ssl for Apache httpd?

Try installing mod_ssl using following command:

yum install mod_ssl

and then reload and restart your Apache server using following commands:

systemctl reload httpd.service
systemctl restart httpd.service

This should work for most of the cases.

Enter export password to generate a P12 certificate

The selected answer apparently does not work anymore in 2019 (at least for me).

I was trying to export a certificate using openssl (version 1.1.0) and the parameter -password doesn't work.

According to that link in the original answer (the same info is in man openssl), openssl has two parameter for passwords and they are -passin for the input parts and -passout for output files.

For the -export command, I used -passin for the password of my key file and -passout to create a new password for my P12 file.

So the complete command without any prompt was like below:

openssl pkcs12 -export -in /tmp/MyCert.crt -inkey /tmp/MyKey.key -out /tmp/MyP12.p12 -name alias -passin pass:keypassphrase -passout pass:certificatepassword

If you does not want a password, you can use pass: like below:

openssl pkcs12 -export -in /tmp/MyCert.crt -inkey /tmp/MyKey.key -out /tmp/MyP12.p12 -name alias -passin pass: -passout pass:

It will works fine with a key without password and the output certificate will be created without password too.

How to change border color of textarea on :focus

you need just in scss varible

$input-btn-focus-width:       .05rem !default;

How to keep the console window open in Visual C++?

Another option is to use

#include <process.h>

Though this is not very portable because it will only work on Windows, but it will automatically print

Press any key to continue...

Android : Capturing HTTP Requests with non-rooted android device

Set a as proxy on a same LAN

  • Open Source
  • Built in python 3
  • Installable via pip

cut or awk command to print first field of first row

sed -n 1p /etc/*release |cut -d " " -f1

if tab delimited:

sed -n 1p /etc/*release |cut -f1

How to test the type of a thrown exception in Jest

I haven't tried it myself, but I would suggest using Jest's toThrow assertion. So I guess your example would look something like this:

it('should throw Error with message \'UNKNOWN ERROR\' when no parameters were passed', (t) => {
  const error = t.throws(() => {
  }, TypeError);

  expect(t).toThrowError('UNKNOWN ERROR');

Again, I haven't test it, but I think it should work.

Does MS SQL Server's "between" include the range boundaries?

The BETWEEN operator is inclusive.

From Books Online:

BETWEEN returns TRUE if the value of test_expression is greater than or equal to the value of begin_expression and less than or equal to the value of end_expression.

DateTime Caveat

NB: With DateTimes you have to be careful; if only a date is given the value is taken as of midnight on that day; to avoid missing times within your end date, or repeating the capture of the following day's data at midnight in multiple ranges, your end date should be 3 milliseconds before midnight on of day following your to date. 3 milliseconds because any less than this and the value will be rounded up to midnight the next day.

e.g. to get all values within June 2016 you'd need to run:

where myDateTime between '20160601' and DATEADD(millisecond, -3, '20160701')


where myDateTime between '20160601 00:00:00.000' and '20160630 23:59:59.997'

datetime2 and datetimeoffset

Subtracting 3 ms from a date will leave you vulnerable to missing rows from the 3 ms window. The correct solution is also the simplest one:

where myDateTime >= '20160601' AND myDateTime < '20160701'

With android studio no jvm found, JAVA_HOME has been set

Just delete the folder highlighted below. Depending on your Android Studio version, mine is 3.5 and reopen Android studio.

enter image description here

C# : assign data to properties via constructor vs. instantiating

Both approaches call a constructor, they just call different ones. This code:

var albumData = new Album 
                     Name = "Albumius",
                     Artist = "Artistus",
                     Year = 2013

is syntactic shorthand for this equivalent code:

var albumData = new Album();
albumData.Name = "Albumius";
albumData.Artist = "Artistus";
albumData.Year = 2013;

The two are almost identical after compilation (close enough for nearly all intents and purposes). So if the parameterless constructor wasn't public:

public Album() { }

then you wouldn't be able to use the object initializer at all anyway. So the main question isn't which to use when initializing the object, but which constructor(s) the object exposes in the first place. If the object exposes two constructors (like the one in your example), then one can assume that both ways are equally valid for constructing an object.

Sometimes objects don't expose parameterless constructors because they require certain values for construction. Though in cases like that you can still use the initializer syntax for other values. For example, suppose you have these constructors on your object:

private Album() { }
public Album(string name)
    this.Name = name;

Since the parameterless constructor is private, you can't use that. But you can use the other one and still make use of the initializer syntax:

var albumData = new Album("Albumius")
                     Artist = "Artistus",
                     Year = 2013

The post-compilation result would then be identical to:

var albumData = new Album("Albumius");
albumData.Artist = "Artistus";
albumData.Year = 2013;

Can someone explain Microsoft Unity?

Unity is a library like many others that allows you to get an instance of a requested type without having to create it yourself. So given.

public interface ICalculator
    void Add(int a, int b);

public class Calculator : ICalculator
    public void Add(int a, int b)
        return a + b;

You would use a library like Unity to register Calculator to be returned when the type ICalculator is requested aka IoC (Inversion of Control) (this example is theoretical, not technically correct).


So now when you want an instance of an ICalculator you just...

Calculator calc = IoCLibrary.Resolve<ICalculator>();

IoC libraries can usually be configured to either hold a singleton or create a new instance every time you resolve a type.

Now let's say you have a class that relies on an ICalculator to be present you could have..

public class BankingSystem
    public BankingSystem(ICalculator calc)
        _calc = calc;

    private ICalculator _calc;

And you can setup the library to inject a object into the constructor when it's created.

So DI or Dependency Injection means to inject any object another might require.

How to get a MemoryStream from a Stream in .NET?

You can simply do:

var ms = new MemoryStream(File.ReadAllBytes(filePath));

Stream position is 0 and ready to use.

How to create a JavaScript callback for knowing when an image is loaded?

these functions will solve the problem, you need to implement the DrawThumbnails function and have a global variable to store the images. I love to get this to work with a class object that has the ThumbnailImageArray as a member variable, but am struggling!

called as in addThumbnailImages(10);

var ThumbnailImageArray = [];

function addThumbnailImages(MaxNumberOfImages)
    var imgs = [];

    for (var i=1; i<MaxNumberOfImages; i++)

    preloadimages(imgs).done(function (images){
            var c=0;

            for(var i=0; i<images.length; i++)
                if(images[i].width >0) 
                    if(c != i)
                        images[c] = images[i];

            images.length = c;


function preloadimages(arr)
    var loadedimages=0
    var postaction=function(){}
    var arr=(typeof arr!="object")? [arr] : arr

    function imageloadpost()
        if (loadedimages==arr.length)
            postaction(ThumbnailImageArray); //call postaction and pass in newimages array as parameter

    for (var i=0; i<arr.length; i++)
        ThumbnailImageArray[i]=new Image();
        ThumbnailImageArray[i].onload=function(){ imageloadpost();};
        ThumbnailImageArray[i].onerror=function(){ imageloadpost();};
    //return blank object with done() method    
    //remember user defined callback functions to be called when images load
    return  { done:function(f){ postaction=f || postaction } };

How to validate domain credentials?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security;
using System.DirectoryServices.AccountManagement;

public struct Credentials
    public string Username;
    public string Password;

public class Domain_Authentication
    public Credentials Credentials;
    public string Domain;

    public Domain_Authentication(string Username, string Password, string SDomain)
        Credentials.Username = Username;
        Credentials.Password = Password;
        Domain = SDomain;

    public bool IsValid()
        using (PrincipalContext pc = new PrincipalContext(ContextType.Domain, Domain))
            // validate the credentials
            return pc.ValidateCredentials(Credentials.Username, Credentials.Password);

LaTeX table positioning

Not necessary to use \restylefloat and destroys other options, like caption placement. just use [H] or [!h] after \begin{table}.

Got a NumberFormatException while trying to parse a text file for objects

The problem might be your split() call. Try just split(" ") without the square brackets.

.NET Core vs Mono

Providing an actual answer.

What is the difference between .Net Core and Mono?

.NET Core now officially is the future of .NET. It started for most part with a re-write of the ASP.NET MVC framework and console applications, which of course includes server applications. (Since it's Turing-complete and supports interop with C dlls, you could, if you absolutely wanted to, also write your own desktop applications with it, for example through 3rd-party libraries like Avalonia, which were a bit very basic at the time I first wrote this, which meant you were pretty much limited to web or server stuff.) Over time, many APIs have been added to .NET Core, so much so that after version 3.1, .NET Core will jump to version 5.0, be known as .NET 5.0 without the "Core", and that then will be the future of the .NET Framework. What used to be the full .NET Framework will linger around in maintenance mode as Full .NET Framework 4.8.x for a few decades, until it will die (maybe there are still going to be some upgrades, but I doubt it). In other words, .NET Core is the future of .NET, and Full .NET Framework will go the way of the Dodo/Silverlight/WindowsPhone.

The main point of .NET Core, apart from multi-platform support, is to improve performance, and to enable "native compilation"/self-contained-deployment (so you don't need .NET framework/VM installed on the target machine.
On the one hand, this means support on Linux, and on the other, self-contained deployment is useful in "cloud-computing", since then you can just use whatever version of the dotnet-CORE framework you like, and you don't have to worry about which version(s) of the .NET framework the sysadmin has actually installed.

While the .NET Core runtime supports multiple operating systems and processors, the SDK is a different story. And while the SDK supports multiple OS, ARM support for the SDK is/was still work in progress. .NET Core is supported by Microsoft. Dotnet-Core did not come with WinForms or WPF or anything like that.

  • As of version 3.0, WinForms and WPF is also supported by .NET Core, but only on Windows, and only by C#. Not by VB.NET (VB.NET support planned for v5 in 2020). And there is no Forms Designer in .NET Core: it's being shipped with a Visual Studio update later, at an unspecified time.
  • WebForms are still not supported by .NET Core, and there are no plans to support them, ever (Blazor is the new kid in town for that).
  • .NET Core also comes with System.Runtime, which replaces mscorelib.
  • Oftentimes, .NET Core is mixed up with NetStandard, which is a bit of a wrapper around System.Runtime/mscorelib (and some others), that allows you to write libraries that target .NET Core, Full .NET Framework and Xamarin (iOS/Android), all at the same time.
  • the .NET Core SDK does not/did not work on ARM, at least not last time I checked.

"The Mono Project" is much older than .NET Core.
Mono is Spanish and means Monkey, and as a side-remark, the name has nothing to do with mononucleosis (hint: you could get a list of staff under
Mono was started in 2005 by Miguel de Icaza (the guy that started GNOME - and a few others) as an implementation of the .NET Framework for Linux (Ximian/SuSe/Novell). Mono includes Web-Forms, Winforms, MVC, Olive, and an IDE called MonoDevelop (also knows as Xamarin Studio or Visual Studio Mac). Basically the equivalent of (OpenJDK) JVM and (OpenJDK) JDK/JRE (as opposed to SUN/Oracle JDK). You can use it to get ASP.NET-WebForms + WinForms + ASP.NET-MVC applications to work on Linux.

Mono is supported by Xamarin (the new company name of what used to be Ximian, when they focused on the Mobile market, instead of the Linux market), and not by Microsoft.
(since Xamarin was bought by Microsoft, that's technically [but not culturally] Microsoft.)
You will usually get your C# stuff to compile on mono, but not the VB.NET stuff.
Mono misses some advanced features, like WSE/WCF and WebParts.
Many of the Mono implementations are incomplete (e.g. throw NotImplementedException in ECDSA encryption), buggy (e.g. ODBC/ADO.NET with Firebird), behave differently than on .NET (for example XML-serialization) or otherwise unstable (ASP.NET MVC) and unacceptably slow (Regex). On the upside, the Mono toolchain also works on ARM.

As far as .NET Core is concerned, when they say cross-platform, don't expect that cross-platform means that you could actually just apt-get install .NET Core on ARM-Linux, like you can with ElasticSearch. You'll have to compile the entire framework from source.
That is, if you have that space (e.g. on a Chromebook, which has a 16 to 32 GB total HD).
It also used to have issues of incompatibility with OpenSSL 1.1 and libcurl.
Those have been rectified in the latest version of .NET Core Version 2.2.
So much for cross-platform.

I found a statement on the official site that said, "Code written for it is also portable across application stacks, such as Mono".

As long as that code doesn't rely on WinAPI-calls, Windows-dll-pinvokes, COM-Components, a case-insensitive file system, the default-system-encoding (codepage) and doesn't have directory separator issues, that's correct. However, .NET Core code runs on .NET Core, and not on Mono. So mixing the two will be difficult. And since Mono is quite unstable and slow (for web applications), I wouldn't recommend it anyway. Try image-processing on .NET core, e.g. WebP or moving GIF or multipage-tiff or writing text on an image, you'll be nastily surprised.

As of .NET Core 2.0, there is System.Drawing.Common (NuGet), which contains most of the functionality of System.Drawing. It should be more or less feature-complete in .NET-Core 2.1. However, System.Drawing.Common uses GDI+, and therefore won't work on Azure (System.Drawing libraries are available in Azure Cloud Service [basically just a VM], but not in Azure Web App [basically shared hosting?])
So far, System.Drawing.Common works fine on Linux/Mac, but has issues on iOS/Android - if it works at all, there.
Prior to .NET Core 2.0, that is to say sometime mid-February 2017, you could use SkiaSharp for imaging (example) (you still can).
Post .net-core 2.0, you'll notice that SixLabors ImageSharp is the way to go, since System.Drawing is not necessarely secure, and has a lot of potential or real memory leaks, which is why you shouldn't use GDI in web-applications; Note that SkiaSharp is a lot faster than ImageSharp, because it uses native-libraries (which can also be a drawback). Also, note that while GDI+ works on Linux & Mac, that doesn't mean it works on iOS/Android.

Code not written for .NET (non-Core) is not portable to .NET Core.
Meaning, if you want a non-GPL C# library like PDFSharp to create PDF-documents (very commonplace), you're out of luck (at the moment) (not anymore). Never mind ReportViewer control, which uses Windows-pInvokes (to encrypt, create mcdf documents via COM, and to get font, character, kerning, font embedding information, measure strings and do line-breaking, and for actually drawing tiffs of acceptable quality), and doesn't even run on Mono on Linux
(I'm working on that).

Also, code written in .NET Core is not portable to Mono, because Mono lacks the .NET Core runtime libraries (so far).

My goal is to use C#, LINQ, EF7, visual studio to create a website that can be ran/hosted in linux.

EF in any version that I tried so far was so goddamn slow (even on such simple things like one table with one left-join), I wouldn't recommend it ever - not on Windows either.
I would particularly not recommend EF if you have a database with unique-constrains, or varbinary/filestream/hierarchyid columns. (Not for schema-update either.)
And also not in a situation where DB-performance is critical (say 10+ to 100+ concurrent users).
Also, running a website/web-application on Linux will sooner or later mean you'll have to debug it.
There is no debugging support for .NET Core on Linux. (Not anymore, but requires JetBrains Rider.)
MonoDevelop does not (yet) support debugging .NET Core projects.
If you have problems, you're on your own. You'll have to use extensive logging.
Be careful, be advised extensive logging will fill your disk in no time, particularly if your program enters an infinite loop or recursion.
This is especially dangerous if your web-app runs as root, because log-in requires logfile-space - if there's no free space left, you won't be able to login anymore.
(Normally, about 5% of diskspace is reserved for user root [aka administrator on Windows], so at least the administrator can still log in if the disk is almost full. But if your applications run as root, that restriction does not apply for their disk usage, and so their logfiles can use 100% of the remaining free space, so not even the administrator can log in any more.)
It's therefore better not to encrypt that disk, that is, if you value your data/system.

Someone told me that he wanted it to be "in Mono", but I don't know what that means.

It either means he doesn't want to use .NET Core, or he just wants to use C# on Linux/Mac. My guess is he just wants to use C# for a Web-App on Linux. .NET Core is the way to go for that, if you absolutely want to do it in C#. Don't go with "Mono proper"; on the surface, it would seem to work at first - but believe me you will regret it because Mono's ASP.NET MVC isn't stable when your server runs long-term (longer than 1 day) - you have now been warned. See also the "did not complete" references when measuring Mono performance on the techempower benchmarks.


I know I want to use the .Net Core 1.0 framework with the technologies I listed above. He also said he wanted to use "fast cgi". I don't know what that means either.

It means he wants to use a high-performance full-featured WebServer like nginx (Engine-X), possibly Apache.
Then he can run mono/dotnetCore with virtual name based hosting (multiple domain names on the same IP) and/or load-balancing. He can also run other websites with other technologies, without requiring a different port-number on the web-server. It means your website runs on a fastcgi-server, and nginx forwards all web-requests for a certain domain via the fastcgi-protocol to that server. It also means your website runs in a fastcgi-pipeline, and you have to be careful what you do, e.g. you can't use HTTP 1.1 when transmitting files.
Otherwise, files will be garbled at the destination.
See also here and here.

To conclude:
.NET Core at present (2016-09-28) is not really portable, nor is is really cross-platform (in particular the debug-tools).
Nor is native-compilation easy, especially for ARM.
And to me, it also does not look like its development is "really finished", yet.
For example, System.Data.DataTable/DataAdaper.Update is missing... (not anymore with .NET Core 2.0)
Together with the System.Data.Common.IDB* interfaces. (not anymore with .NET Core 1.1)
if there ever was one class that is often used, DataTable/DataAdapter would be it...
Also, the Linux-installer (.deb) fails, at least on my machine, and I'm sure I'm not the only one that has that problem.
Debug, maybe with Visual Studio Code, if you can build it on ARM (I managed to do that - do NOT follow Scott Hanselman's blog-post if you do that - there's a howto in the wiki of VS-Code on github), because they don't offer the executable.
Yeoman also fails. (I guess it has something to do with the nodejs version you installed - VS Code requires one version, Yeoman another... but it should run on the same computer. pretty lame
Never mind that it should run on the node version shipped by default on the OS.
Never mind that there should be no dependency on NodeJS in the first place.
The kestell server is also work in progress.
And judging by my experience with the mono-project, I highly doubt they ever tested .NET Core on FastCGI, or that they have any idea what FastCGI-support means for their framework, let alone that they tested it to make sure "everything works". In fact, I just tried making a fastcgi-application with .NET Core and just realized there is no FastCGI library for .NET Core "RTM"...

So when you're going to run .NET Core "RTM" behind nginx, you can only do it by proxying requests to kestrell (that semi-finished nodeJS-derived web-server) - there's no fastcgi support at present in .NET Core "RTM", AFAIK. Since there is no .net core fastcgi library, and no samples, it's also highly unlikely that anybody did any testing on the framework to make sure fastcgi works as expected.

I also question the performance.
In the (preliminary) techempower-benchmark (round 13), aspnetcore-linux ranks on 25% relative to the best performance, while comparable frameworks like Go (golang) rank at 96.9% of peak performance (and that is when returning plaintext without file-system access only). .NET Core does a little better on JSON-serialization, but it does not look compelling either (go reaches 98.5% of peak, .NET core 65%). That said, it can't possibly be worse than "mono proper".

Also, since it's still relatively new, not all of the major libraries have been ported (yet), and I doubt that some of them will ever be ported.
Imaging support is also questionable at best.
For anything encryption, use BouncyCastle instead.

Can you help me make sense of all these terms and if my expectations are realistic?

I hope i helped you making more sense with all these terms.
As far as your expecations go:
Developing a Linux application without knowing anything about Linux is a really stupid idea in the first place, and it's also bound to fail in some horrible way one way or the other. That said, because Linux comes at no licensing costs, it's a good idea in principle, BUT ONLY IF YOU KNOW WHAT YOU DO.
Developing an application for a platform where you can't debug your application on is another really bad idea.
Developing for fastcgi without knowing what consequences there are is yet another really bad idea.

Doing all these things on a "experimental" platform without any knowledge of that platform's specifics and without debugging support is suicide, if your project is more than just a personal homepage. On the other hand, I guess doing it with your personal homepage for learning purposes would probably be a very good experience - then you get to know what the framework and what the non-framework problems are.
You can for example (programmatically) loop-mount a case-insensitive fat32, hfs or JFS for your application, to get around the case-sensitivity issues (loop-mount not recommended in production).

To summarize
At present (2016-09-28), I would stay away from .NET Core (for production usage). Maybe in one to two years, you can take another look, but probably not before.
If you have a new web-project that you develop, start it in .NET Core, not mono.

If you want a framework that works on Linux (x86/AMD64/ARMhf) and Windows and Mac, that has no dependencies, i.e. only static linking and no dependency on .NET, Java or Windows, use Golang instead. It's more mature, and its performance is proven (Baidu uses it with 1 million concurrent users), and golang has a significantly lower memory footprint. Also golang is in the repositories, the .deb installs without problems, the sourcecode compiles - without requiring changes - and golang (in the meantime) has debugging support with delve and JetBrains Gogland on Linux (and Windows and Mac). Golang's build process (and runtime) also doesn't depend on NodeJS, which is yet another plus.

As far as mono goes, stay away from it.
It is nothing short of amazing how far mono has come, but unfortunately that's no substitute for its performance/scalability and stability issues for production applications.
Also, mono-development is quite dead, they largely only develop the parts relevant to Android and iOS anymore, because that's where Xamarin makes their money.
Don't expect Web-Development to be a first-class Xamarin/mono citizen.
.NET Core might be worth it, if you start a new project, but for existing large web-forms projects, porting over is largely out of the question, the changes required are huge. If you have a MVC-project, the amount of changes might be manageable, if your original application design was sane, which is mostly not the case for most existing so-called "historically grown" applications.

December 2016 Update:
Native compilation has been removed from .NET Core preview, as it is not yet ready...

Seems like they have improved pretty heavily on the raw text-file benchmark, but on the other hand, it's gotten pretty buggy. Also, it further deteriorated in the JSON benchmarks. Curious also that entity framework shall be faster for updates than Dapper - although both at record slowness. This is very unlikely to be true. Looks like there still are more than just a few bugs to hunt.

Also, there seems to be relief coming on the Linux IDE front.
JetBrains released "Project Rider", an early access preview of a C#/.NET Core IDE for Linux (and Mac and Windows), that can handle Visual Studio Project files. Finally a C# IDE that is usable & that isn't slow as hell.

Conclusion: .NET Core still is pre-release quality software as we march into 2017. Port your libraries, but stay away from it for production usage, until framework quality stabilizes.
And keep an eye on Project Rider.

buggy .net core

2017 Update
Have migrated my (brother's) homepage to .NET Core for now.
So far, the runtime on Linux seems to be stable enough (at least for small projects) - it survived a load test with ease - mono never did.
Also, it looks like I mixed up .NET-Core-native and .NET-Core-self-contained-deployment. Self-contained deployment works, but it is a bit underdocumented, although it's super easy (the build/publish tools are a bit unstable, yet - if you encounter "Positive number required. - Build FAILED." - run the same command again, and it works).

You can run

dotnet restore -r win81-x64
dotnet build -r win81-x64
dotnet publish -f netcoreapp1.1 -c Release -r win81-x64

Note: As per .NET Core 3, you can publish everything minified as a single file:

dotnet publish -r win-x64 -c Release /p:PublishSingleFile=true
dotnet publish -r linux-x64 -c Release /p:PublishSingleFile=true

However, unlike go, it's not a statically linked executable, but a self-extracting zip file, so when deploying, you might run into problems, especially if the temp directory is locked down by group policy, or some other issues. Works fine for a hello-world program, though. And if you don't minify, the executable size will clock in at something around 100 MB.

And you get a self-contained .exe-file (in the publish directory), which you can move to a Windows 8.1 machine without .NET framework installed and let it run. Nice. It's here that dotNET-Core just starts to get interesting. (mind the gaps, SkiaSharp doesn't work on Windows 8.1 / Windows Server 2012 R2, [yet] - the ecosystem has to catch up first - but interestingly, the Skia-dll-load-fail doesn't crash the entire server/application - so everything else works)

(Note: SkiaSharp on Windows 8.1 is missing the appropriate VC runtime files - msvcp140.dll and vcruntime140.dll. Copy them into the publish-directory, and Skia will work on Windows 8.1.)

August 2017 Update
.NET Core 2.0 released.
Be careful - comes with (huge breaking) changes in authentication...
On the upside, it brought the DataTable/DataAdaper/DataSet classes back, and many more.
Realized .NET Core is still missing support for Apache SparkSQL, because Mobius isn't yet ported. That's bad, because that means no SparkSQL support for my IoT Cassandra Cluster, so no joins...
Experimental ARM support (runtime only, not SDK - too bad for devwork on my Chromebook - looking forward to 2.1 or 3.0).
PdfSharp is now experimentally ported to .NET Core.
JetBrains Rider left EAP. You can now use it to develop & debug .NET Core on Linux - though so far only .NET Core 1.1 until the update for .NET Core 2.0 support goes live.

May 2018 Update
.NET Core 2.1 release imminent. Maybe this will fix NTLM-authentication on Linux (NTLM authentication doesn't work on Linux {and possibly Mac} in .NET-Core 2.0 with multiple authenticate headers, such as negotiate, commonly sent with ms-exchange, and they're apparently only fixing it in v2.1, no bugfix release for 2.0).
But I'm not installing preview releases on my machine. So waiting.
v2.1 is also said to greatly reduce compile times. That would be good.

Also, note that on Linux, .NET Core is 64-Bit only !
There is no, and there will be no, x86-32 version of .NET Core on Linux.
And the ARM port is ARM-32 only. No ARM-64, yet.
And on ARM, you (at present) only have the runtime, not the dotnet-SDK.

And one more thing:
Because .NET-Core uses OpenSSL 1.0, .NET Core on Linux doesn't run on Arch Linux, and by derivation not on Manjaro (the most popular Linux distro by far at this point in time), because Arch Linux uses OpenSSL 1.1. So if you're using Arch Linux, you're out of luck (with Gentoo, too).


Latest version of .NET Core 2.2+ supports OpenSSL 1.1. So you can use it on Arch or (k)Ubuntu 19.04+. You might have to use the .NET-Core install script though, because there are no packages, yet.

On the upside, performance has definitely improved: fortunes


.NET Core 3:
.NET-Core v 3.0 is said to bring WinForms and WPF to .NET-Core.
However, while WinForms and WPF will be .NET Core, WinForms and WPF in .NET-Core will run on Windows only, because WinForms/WPF will use the Windows-API.

.NET Core 3.0 is now out (RTM), and there is WinForms and WPF support, but only for C# (on Windows). There is no WinForms-Core-Designer. The designer will, eventually, come with a Visual Studio update, somewhen. WinForms support for VB.NET is not supported, but is planned for .NET 5.0 somewhen in 2020.


echo "DOTNET_CLI_TELEMETRY_OPTOUT=1" >> /etc/environment

If you've used it on windows, you probably never saw this:

The .NET Core tools collect usage data in order to improve your experience.
The data is anonymous and does not include command-line arguments.
The data is collected by Microsoft and shared with the community.
You can opt out of telemetry by setting a DOTNET_CLI_TELEMETRY_OPTOUT environment variable to 1 using your favorite shell.
You can read more about .NET Core tools telemetry @

I thought I'd mention that I think monodevelop (aka Xamarin Studio, the Mono IDE, or Visual Studio Mac as it is now called on Mac) has evolved quite nicely, and is - in the meantime - largely usable.
However, JetBrains Rider (2018 EAP at this point in time) is definitely a lot nicer and more reliable (and the included decompiler is a life-safer), that is to say, if you develop .NET-Core on Linux or Mac. MonoDevelop does not support Debug-StepThrough on Linux in .NET Core, though, since MS does not license their debugging API dll (except for VisualStudio Mac ... ). However, you can use the Samsung debugger for .NET Core through the .NET Core debugger extension for Samsung Debugger for MonoDevelop

I don't use Mac, so I can't say if what I wrote here applies to FreeBSD-Unix based Mac as well. I am refering to the Linux (Debian/Ubuntu/Mint) version of JetBrains Rider, mono, MonoDevelop/VisualStudioMac/XamarinStudio and .NET-Core. Also, Apple is contemplating a move from Intel-processors to self-manufactured ARM(ARM-64?)-based processors, so much of what applies to Mac right now might not apply to Mac in the future (2020+).

Also, when I write "mono is quite unstable and slow", the unstable relates to WinFroms & WebForms applications, specifically executing web-applications via fastcgi or with XSP (on the 4.x version of mono), as well as XML-serialization-handling peculiarities, and the quite-slow relates to WinForms, and regular expressions in particular (ASP.NET-MVC uses regular expressions for routing as well).

When I write about my experience about mono 2.x, 3.x and 4.x, that also does not necessarely mean these issues haven't been resolved by now, or by the time you are reading this, nor that if they are fixed now, that there can't be a regression later that reintroduces any of these bugs/features. Nor does that mean that if you embed the mono-runtime, you'll get the same results as when you use the (dev) system's mono runtime. It also doesn't mean that embedding the mono-runtime (anywhere) is necessarely free.

All that doesn't necessarely mean mono is ill-suited for iOS or Android, or that it has the same issues there. I don't use mono on Android or IOS, so I'm in no positon to say anything about stability, usability, costs and performance on these platforms. Obviously, if you use .NET on Android, you have some other costs considerations to do as well, such as weighting xamarin-costs vs. costs and time for porting existing code to Java. One hears mono on Android and IOS shall be quite good. Take it with a grain of salt. For one, don't expect the default-system-encoding to be the same on android/ios vs. Windows, and don't expect the android filesystem to be case-insensitive, and don't expect any windows fonts to be present.

How to return a resolved promise from an AngularJS Service using $q?

Return your promise , return deferred.promise.
It is the promise API that has the 'then' method.$q

Calling resolve does not return a promise it only signals the promise that the promise is resolved so it can execute the 'then' logic.

Basic pattern as follows, rinse and repeat

<!DOCTYPE html>

  <script data-require="angular.js@*" data-semver="1.3.0-beta.5" 
  <link rel="stylesheet" href="style.css" />
  <script src="script.js"></script>


<div ng-controller="test">
  <button ng-click="test()">test</button>
  var app = angular.module("app",[]);


    $scope.$test = function(){
      var deferred = $q.defer();
      return deferred.promise;




Text size and different android screen sizes

I know it's late but this might help someone...


        android:text="Your text goes here!"
        app:layout_constraintWidth_percent="0.50" />

Also, if you want to adjust the text size then try changing


That's all.

Sorting an ArrayList of objects using a custom sorting order

By using lambdaj you can sort a collection of your contacts (for example by their name) as it follows

sort(contacts, on(Contact.class).getName());

or by their address:

sort(contacts, on(Contacts.class).getAddress());

and so on. More in general, it offers a DSL to access and manipulate your collections in many ways, like filtering or grouping your contacts based on some conditions, aggregate some of their property values, etc.

Using Excel VBA to run SQL query

Below is code that I currently use to pull data from a MS SQL Server 2008 into VBA. You need to make sure you have the proper ADODB reference [VBA Editor->Tools->References] and make sure you have Microsoft ActiveX Data Objects 2.8 Library checked, which is the second from the bottom row that is checked (I'm using Excel 2010 on Windows 7; you might have a slightly different ActiveX version, but it will still begin with Microsoft ActiveX):

References required for SQL

Sub Module for Connecting to MS SQL with Remote Host & Username/Password

Sub Download_Standard_BOM()
'Initializes variables
Dim cnn As New ADODB.Connection
Dim rst As New ADODB.Recordset
Dim ConnectionString As String
Dim StrQuery As String

'Setup the connection string for accessing MS SQL database
   'Make sure to change:
       '1: PASSWORD
       '2: USERNAME
       '4: DATABASE
    ConnectionString = "Provider=SQLOLEDB.1;Password=PASSWORD;Persist Security Info=True;User ID=USERNAME;Data Source=REMOTE_IP_ADDRESS;Use Procedure for Prepare=1;Auto Translate=True;Packet Size=4096;Use Encryption for Data=False;Tag with column collation when possible=False;Initial Catalog=DATABASE"

    'Opens connection to the database
    cnn.Open ConnectionString
    'Timeout error in seconds for executing the entire query; this will run for 15 minutes before VBA timesout, but your database might timeout before this value
    cnn.CommandTimeout = 900

    'This is your actual MS SQL query that you need to run; you should check this query first using a more robust SQL editor (such as HeidiSQL) to ensure your query is valid
    StrQuery = "SELECT TOP 10 * FROM tbl_table"

    'Performs the actual query
    rst.Open StrQuery, cnn
    'Dumps all the results from the StrQuery into cell A2 of the first sheet in the active workbook
    Sheets(1).Range("A2").CopyFromRecordset rst
End Sub

jQuery - Disable Form Fields

The jQuery docs say to use prop() for things like disabled, checked, etc. Also the more concise way is to use their selectors engine. So to disable all form elements in a div or form parent.


And to enable again you could do


How to rebase local branch onto remote master

Step 1:

git fetch origin

Step 2:

git rebase origin/master

Step 3:(Fix if any conflicts)

git add .

Step 4:

git rebase --continue

Step 5:

git push --force

Count Vowels in String Python


S = "Combination"

import re
print re.findall('a|e|i|o|u', S)

Prints: ['o', 'i', 'a', 'i', 'o']

For your case in a sentence (Case1):

txt = "blah blah blah...."

import re
txt = re.sub('[\r\t\n\d\,\.\!\?\\\/\(\)\[\]\{\}]+', " ", txt)
txt = re.sub('\s{2,}', " ", txt)
txt = txt.strip()
words = txt.split(' ')

for w in words:
    print w, len(re.findall('a|e|i|o|u', w))


import re,  from nltk.tokenize import word_tokenize

for w in work_tokenize(txt):
        print w, len(re.findall('a|e|i|o|u', w))

How to check if BigDecimal variable == 0 in java?

There is a static constant that represents 0:


You should do this instead of:


in order to avoid the case where selectPrice is null.

sprintf like functionality in Python

Two approaches are to write to a string buffer or to write lines to a list and join them later. I think the StringIO approach is more pythonic, but didn't work before Python 2.6.

from io import StringIO

with StringIO() as s:
   print("Hello", file=s)
   print("Goodbye", file=s)
   # And later...
   with open('myfile', 'w') as f:

You can also use these without a ContextMananger (s = StringIO()). Currently, I'm using a context manager class with a print function. This fragment might be useful to be able to insert debugging or odd paging requirements:

class Report:
    ... usual init/enter/exit
    def print(self, *args, **kwargs):
        with StringIO() as s:
            print(*args, **kwargs, file=s)
            out = s.getvalue()
        ... stuff with out

with Report() as r:
   r.print(f"This is {}!", 'Yikes!', end=':')

Remove all constraints affecting a UIView

Based on previous answers (swift 4)

You can use immediateConstraints when you don't want to crawl entire hierarchies.

extension UIView {
 * Deactivates immediate constraints that target this view (self + superview)
func deactivateImmediateConstraints(){
 * Deactivates all constrains that target this view
func deactiveAllConstraints(){
 * Gets self.constraints + superview?.constraints for this particular view
var immediateConstraints:[NSLayoutConstraint]{
    let constraints = self.superview?.constraints.filter{
        $0.firstItem as? UIView === self || $0.secondItem as? UIView === self
        } ?? []
    return self.constraints + constraints
 * Crawls up superview hierarchy and gets all constraints that affect this view
var allConstraints:[NSLayoutConstraint] {
    var view: UIView? = self
    var constraints:[NSLayoutConstraint] = []
    while let currentView = view {
        constraints += currentView.constraints.filter {
            return $0.firstItem as? UIView === self || $0.secondItem as? UIView === self
        view = view?.superview
    return constraints

How to add include and lib paths to configure/make cycle?

Set LDFLAGS and CFLAGS when you run make:

$ LDFLAGS="-L/home/me/local/lib" CFLAGS="-I/home/me/local/include" make

If you don't want to do that a gazillion times, export these in your .bashrc (or your shell equivalent). Also set LD_LIBRARY_PATH to include /home/me/local/lib:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/me/local/lib

Add a properties file to IntelliJ's classpath

This is one of the dumb mistakes I've done. I spent a lot of time trying to debug this problem and tried all the responses posted above, but in the end, it was one of my many dumb mistakes.

I was using org.apache.logging.log4j.Logger (:fml:) whereas I should have used org.apache.log4j.Logger. Using this correct logger saved my evening.

Disabling Log4J Output in Java

In addition, it is also possible to turn logging off programmatically:



Logger.getRootLogger().addAppender(new NullAppender());

These use imports:

import org.apache.log4j.Logger;
import org.apache.log4j.Level;
import org.apache.log4j.NullAppender;

Fatal error: Call to undefined function pg_connect()

If you got php5.6 using the ppa repository,

then you should install the package using:

sudo apt install php5.6-pgsql

Finally, if you use apache2, restart it:

sudo service apache2 restart

How to use OrderBy with findAll in Spring Data

Please have a look at the Spring Data JPA - Reference Documentation, section 5.3. Query Methods, especially at section 5.3.2. Query Creation, in "Table 3. Supported keywords inside method names" (links as of 2019-05-03).

I think it has exactly what you need and same query as you stated should work...

How to concatenate properties from multiple JavaScript objects

function Collect(a, b, c) {
    for (property in b)
        a[property] = b[property];

    for (property in c)
        a[property] = c[property];

    return a;

Notice: Existing properties in previous objects will be overwritten.

@Html.DisplayFor - DateFormat ("mm/dd/yyyy")

Maybe try simply

@(Model.AuditDate.HasValue ? Model.AuditDate.ToString("mm/dd/yyyy") : String.Empty)

also you can use many type of string format like .ToString("dd MMM, yyyy") .ToString("d") etc

use localStorage across subdomains

This is how:

[November 2020 Update: This solution relies on being able to set document.domain. The ability to do that has now been deprecated, unfortunately.]

For sharing between subdomains of a given superdomain (e.g., there's a technique you can use in that situation. It can be applied to localStorage, IndexedDB, SharedWorker, BroadcastChannel, etc, all of which offer shared functionality between same-origin pages, but for some reason don't respect any modification to document.domain that would let them use the superdomain as their origin directly.

(1) Pick one "main" domain to for the data to belong to: i.e. either or will hold your localStorage data. Let's say you pick

(2) Use localStorage normally for that chosen domain's pages.

(3) On all pages (the other domain), use javascript to set document.domain = "";. Then also create a hidden <iframe>, and navigate it to some page on the chosen domain (It doesn't matter what page, as long as you can insert a very little snippet of javascript on there. If you're creating the site, just make an empty page specifically for this purpose. If you're writing an extension or a Greasemonkey-style userscript and so don't have any control over pages on the server, just pick the most lightweight page you can find and insert your script into it. Some kind of "not found" page would probably be fine).

(4) The script on the hidden iframe page need only (a) set document.domain = "";, and (b) notify the parent window when this is done. After that, the parent window can access the iframe window and all its objects without restriction! So the minimal iframe page is something like:

<!doctype html>
    document.domain = "";
    window.parent.iframeReady();  // function defined & called on parent window

If writing a userscript, you might not want to add externally-accessible functions such as iframeReady() to your unsafeWindow, so instead a better way to notify the main window userscript might be to use a custom event:

    window.parent.dispatchEvent(new CustomEvent("iframeReady"));

Which you'd detect by adding a listener for the custom "iframeReady" event to your main page's window.

(NOTE: You need to set document.domain = "" even if the iframe's domain is already Assigning a value to document.domain implicitly sets the origin's port to null, and both ports must match for the iframe and its parent to be considered same-origin. See the note here:

(5) Once the hidden iframe has informed its parent window that it's ready, script in the parent window can just use iframe.contentWindow.localStorage, iframe.contentWindow.indexedDB, iframe.contentWindow.BroadcastChannel, iframe.contentWindow.SharedWorker instead of window.localStorage, window.indexedDB, etc. ...and all these objects will be scoped to the chosen origin - so they'll have the this same shared origin for all of your pages!

The most awkward part of this technique is that you have to wait for the iframe to load before proceeding. So you can't just blithely start using localStorage in your DOMContentLoaded handler, for example. Also you might want to add some error handling to detect if the hidden iframe fails to load correctly.

Obviously, you should also make sure the hidden iframe is not removed or navigated during the lifetime of your page... OTOH I don't know what the result of that would be, but very likely bad things would happen.

And, a caveat: setting/changing document.domain can be blocked using the Feature-Policy header, in which case this technique will not be usable as described.

However, there is a significantly more-complicated generalization of this technique, that can't be blocked by Feature-Policy, and that also allows entirely unrelated domains to share data, communications, and shared workers (i.e. not just subdomains off a common superdomain). @Mayank Jain already described it in their answer, namely:

The general idea is that, just as above, you create a hidden iframe to provide the correct origin for access; but instead of then just grabbing the iframe window's properties directly, you use script inside the iframe to do all of the work, and you communicate between the iframe and your main window only using postMessage() and addEventListener("message",...).

This works because postMessage() can be used even between different-origin windows. But it's also significantly more complicated because you have to pass everything through some kind of messaging infrastructure that you create between the iframe and the main window, rather than just using the localStorage, IndexedDB, etc. APIs directly in your main window's code.

System.web.mvc missing

Easiest way to solve this problem is install ASP.NET MVC 3 from Web Platforms installer.

enter image description here

Or by using Nuget command

Install-Package Microsoft.AspNet.Mvc -Version 3.0.50813.1

Git: How to squash all commits on branch

Although this answer is a bit verbose it does allow you to create a single commit branch by doing a single merge with another branch. (No rebasing/squashing/merging individual commits).

Since we don't care about the in-between commits we can use a simple solution:

# Merge and resolve conflicts
git merge origin/master

# Soft reset and create a HEAD with the version you want
git reset --soft origin/master
git commit -m "Commit message"
git push origin your-branch -f

... then to remove the history...

# Get the most up-to-date master
git checkout master
git reset --hard

# Create a temporary branch
git checkout -b temp-branch

# Retrieve the diff between master and your-branch and commit with a single commit
git checkout origin/your-branch
git commit -m "Feature commit"

# Force push to the feature branch
git push origin temp-branch:your-branch -f

# Clean up
git checkout your-branch
git branch -D temp-branch

This can all be put into a bash function with 3 params like so squashall --their master --mine your-branch --msg "Feature commit" and it will work as long as you have the correct version of files locally.

Wait on the Database Engine recovery handle failed. Check the SQL server error log for potential causes

This post is high up when you google that error message, which I got when installing security patch KB4505224 on SQL Server 2017 Express i.e. None of the above worked for me, but did consume several hours trying.

The solution for me, partly from here was:

  1. uninstall SQL Server
  2. in Regional Settings / Management / System Locale, "Beta: UTF-8 support" should be OFF
  3. re-install SQL Server
  4. Let Windows install the patch.

And all was well.

More on this here.

Why use multiple columns as primary keys (composite primary key)

Using a primary key on multiple tables comes in handy when you're using an intermediate table in a relational database.

I'll use a database I once made for an example and specifically three tables within that table. I creäted a database for a webcomic some years ago. One table was called "comics"—a listing of all comics, their titles, image file name, etc. The primary key was "comicnum".

The second table was "characters"—their names and a brief description. The primary key was on "charname".

Since each comic—with some exceptions—had multiple characters and each character appeared within multiple comics, it was impractical to put a column in either "characters" or "comics" to reflect that. Instead, I creäted a third table was called "comicchars", and that was a listing of which characters appeared in which comics. Since this table essentially joined the two tables, it needed but two columns: charname and comicnum, and the primary key was on both.

PHP Swift mailer: Failed to authenticate on SMTP using 2 possible authenticators

First check if there is any connectivity problem and you can reach the SMTP server:

In terminal type:

telnet servername portnumber 

If you receive the 220 response you can reach the SMTP server and there is no connectivity problem but if the connection to the server failed see what's wrong in your network.

If the server needs auth try to authenticate on the server by username and password and see if something goes wrong.

At last see if the server requires encryption and if yes openssl and other stuff are configured correctly.

How to find and replace all occurrences of a string recursively in a directory tree?

Try this:

grep -rl 'SearchString' ./ | xargs sed -i 's/REPLACESTRING/WITHTHIS/g'

grep -rl will recursively search for the SEARCHSTRING in the directories ./ and will replace the strings using sed.


Replacing a name TOM with JERRY using search string as SWATKATS in directory CARTOONNETWORK

grep -rl 'SWATKATS' CARTOONNETWORK/ | xargs sed -i 's/TOM/JERRY/g'

This will replace TOM with JERRY in all the files and subdirectories under CARTOONNETWORK wherever it finds the string SWATKATS.

Checking if a key exists in a JavaScript object?

While this doesn't necessarily check if a key exists, it does check for the truthiness of a value. Which undefined and null fall under.


This solution works best for me because I use typescript, and using strings like so 'foo' in obj or obj.hasOwnProperty('foo') to check whether a key exists or not does not provide me with intellisense.

How to read a file in Groovy into a string?

String fileContents = new File('/path/to/file').text

If you need to specify the character encoding, use the following instead:

String fileContents = new File('/path/to/file').getText('UTF-8')

Check if returned value is not null and if so assign it, in one line, with one method call

Since Java 9 you have Objects#requireNonNullElse which does:

public static <T> T requireNonNullElse(T obj, T defaultObj) {
    return (obj != null) ? obj : requireNonNull(defaultObj, "defaultObj");

Your code would be

dinner = Objects.requireNonNullElse(cage.getChicken(), getFreeRangeChicken());

Which is 1 line and calls getChicken() only once, so both requirements are satisfied.

Note that the second argument cannot be null as well; this method forces non-nullness of the returned value.

Consider also the alternative Objects#requireNonNullElseGet:

public static <T> T requireNonNullElseGet(T obj, Supplier<? extends T> supplier)

which does not even evaluate the second argument if the first is not null, but does have the overhead of creating a Supplier.

OperationalError, no such column. Django

I see we have the same problem here, I have the same error. I want to write this for the future user who will experience the same error. After making changes to your class Snippet model like @Burhan Khalid said, you must migrate tables:

python makemigrations snippets
python migrate

And that should resolve the error. Enjoy.

Variable length (Dynamic) Arrays in Java

I answered this question and no you do not need an arraylist or any other thing this was an assignment and I completed it so yes arrays can increase in size. Here is the link How to use Java Dynamic Array and here is the link for my question which i answered Java Dynamic arrays

How to detect when WIFI Connection has been established in Android?

You can start a wifi connection if you give the user a choice to override the normal behavior of asking each time.

I choose to use three methods...

public boolean isOnline() 
 ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
 NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
 return (networkInfo != null && networkInfo.isConnected());

This is quick check if there is an internet connect either Wifi or CellData. From here you can choose what action you want to take. Is it in Airplane mode needs to be checked also.

On a separate thread. I set a variable IpAddress to = " " And poll until I have a valid an ip address.

  WifiManager wifi;
  wifi = (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
  WifiInfo wifiInfo = wifi.getConnectionInfo();
  int ipAddress = wifiInfo.getIpAddress();
  String ip = null;
  ip = String.format("%d.%d.%d.%d",
  (ipAddress & 0xff),
  (ipAddress >> 8 & 0xff),
  (ipAddress >> 16 & 0xff),
  (ipAddress >> 24 & 0xff));
  Log.e(" >>IP number Begin ",ip);

Another code snippet... If its not on turn it on (with users prior permission)


Python popen command. Wait until the command is finished

wait() works fine for me. The subprocesses p1, p2 and p3 are executed at the same. Therefore, all processes are done after 3 seconds.

import subprocess

processes = []

p1 = subprocess.Popen("sleep 3", stdout=subprocess.PIPE, shell=True)
p2 = subprocess.Popen("sleep 3", stdout=subprocess.PIPE, shell=True)
p3 = subprocess.Popen("sleep 3", stdout=subprocess.PIPE, shell=True)


for p in processes:
    if p.wait() != 0:
        print("There was an error")

print("all processed finished")

Disable single warning error

#pragma push/pop are often a solution for this kind of problems, but in this case why don't you just remove the unreferenced variable?

    // ...
catch(const your_exception_type &) // type specified but no variable declared
    // ...

What is a unix command for deleting the first N characters of a line?

tail -f logfile | grep org.springframework | cut -c 900-

would remove the first 900 characters

cut uses 900- to show the 900th character to the end of the line

however when I pipe all of this through grep I don't get anything

Initialization of all elements of an array to one default value in C++?

For the case of an array of single-byte elements, you can use memset to set all elements to the same value.

There's an example here.

how to always round up to the next integer

I think the easiest way is to divide two integers and increase by one :

int r = list.Count() / 10;
r += (list.Count() % 10 == 0 ? 0 : 1);

No need of libraries or functions.

edited with the right code.

C: printf a float value

Use %.6f. This will print 6 decimals.

in python how do I convert a single digit number into a double digits string?

Based on what @user225312 said, you can use .zfill() to add paddng to numbers converted to strings.

My approach is to leave number as a number until the moment you want to convert it into string:

>>> num = 11
>>> padding = 3
>>> print(str(num).zfill(padding))

Out-File -append in Powershell does not produce a new line and breaks string into characters

Add-Content is default ASCII and add new line however Add-Content brings locked files issues too.

How do I return multiple values from a function in C?

One approach is to use macros. Place this in a header file multitype.h

#include <stdlib.h>

/* ============================= HELPER MACROS ============================= */

/* __typeof__(V) abbreviation */

#define TOF(V) __typeof__(V)

/* Expand variables list to list of typeof and variable names */

#define TO3(_0,_1,_2,_3) TOF(_0) v0; TOF(_1) v1; TOF(_2) v2; TOF(_3) v3;
#define TO2(_0,_1,_2)    TOF(_0) v0; TOF(_1) v1; TOF(_2) v2;
#define TO1(_0,_1)       TOF(_0) v0; TOF(_1) v1;
#define TO0(_0)          TOF(_0) v0;

#define TO_(_0,_1,_2,_3,TO_MACRO,...) TO_MACRO

#define TO(...) TO_(__VA_ARGS__,TO3,TO2,TO1,TO0)(__VA_ARGS__)

/* Assign to multitype */

#define MTA3(_0,_1,_2,_3) _0 = mtr.v0; _1 = mtr.v1; _2 = mtr.v2; _3 = mtr.v3;
#define MTA2(_0,_1,_2)    _0 = mtr.v0; _1 = mtr.v1; _2 = mtr.v2;
#define MTA1(_0,_1)       _0 = mtr.v0; _1 = mtr.v1;
#define MTA0(_0)          _0 = mtr.v0;

#define MTA_(_0,_1,_2,_3,MTA_MACRO,...) MTA_MACRO

#define MTA(...) MTA_(__VA_ARGS__,MTA3,MTA2,MTA1,MTA0)(__VA_ARGS__)

/* Return multitype if multiple arguments, return normally if only one */

#define MTR1(...) {                                                           \
    typedef struct mtr_s {                                                    \
      TO(__VA_ARGS__)                                                         \
    } mtr_t;                                                                  \
    mtr_t *mtr = malloc(sizeof(mtr_t));                                       \
    *mtr = (mtr_t){__VA_ARGS__};                                              \
    return mtr;                                                               \

#define MTR0(_0) return(_0)

#define MTR_(_0,_1,_2,_3,MTR_MACRO,...) MTR_MACRO

/* ============================== API MACROS =============================== */

/* Declare return type before function */

typedef void* multitype;

#define multitype(...) multitype

/* Assign return values to variables */

#define let(...)                                                              \
  for(int mti = 0; !mti;)                                                     \
    for(multitype mt; mti < 2; mti++)                                         \
      if(mti) {                                                               \
        typedef struct mtr_s {                                                \
          TO(__VA_ARGS__)                                                     \
        } mtr_t;                                                              \
        mtr_t mtr = *(mtr_t*)mt;                                              \
        MTA(__VA_ARGS__)                                                      \
        free(mt);                                                             \
      } else                                                                  \

/* Return */

#define RETURN(...) MTR_(__VA_ARGS__,MTR1,MTR1,MTR1,MTR0)(__VA_ARGS__)

This makes it possible to return up to four variables from a function and assign them to up to four variables. As an example, you can use them like this:

multitype (int,float,double) fun() {
    int a = 55;
    float b = 3.9;
    double c = 24.15;

    RETURN (a,b,c);

int main(int argc, char *argv[]) {
    int x;
    float y;
    double z;

    let (x,y,z) = fun();

    printf("(%d, %f, %g\n)", x, y, z);

    return 0;

This is what it prints:

(55, 3.9, 24.15)

The solution may not be as portable because it requires C99 or later for variadic macros and for-statement variable declarations. But I think it was interesting enough to post here. Another issue is that the compiler will not warn you if you assign them the wrong values, so you have to be careful.

Additional examples, and a stack-based version of the code using unions, are available at my github repository.

How to link 2 cell of excel sheet?

I Found Solution Of You Question But In Stack Not Allow to Upload Video See the link below it show better explain

How to link two (multiple) workbooks and cells in Excel...

Android - Set text to TextView

Well, @+id/listaVista ListView is drawn after @+id/texto and on top of it. So change in ListView from:




Also, since the list is drawn after textview, I find it dangerous to have android:layout_alignRight="@+id/listaVista" in TextView. So remove it and find another way of aligning.

EDIT Taking a second look at your layout I think this is what you really want to have:

<RelativeLayout xmlns:android=""
    tools:context=".EnviarMensaje" >

        android:text="Escriba el mensaje y luego clickee el canal a ser enviado"
        android:textSize="20sp" />

        android:inputType="text" />

        android:text="TextView" />

        android:layout_below="@+id/editText1" >


How To Set Text In An EditText

You can set android:text="your text";


Find MongoDB records where array field is not empty

Use the $elemMatch operator: according to the documentation

The $elemMatch operator matches documents that contain an array field with at least one element that matches all the specified query criteria.

$elemMatches makes sure that the value is an array and that it is not empty. So the query would be something like

ME.find({ pictures: { $elemMatch: {$exists: true }}})

PS A variant of this code is found in MongoDB University's M121 course.

Binding value to input in Angular JS

Use ng-value for set value of input box after clicking on a button:

"input type="email"  class="form-control" id="email2" ng-value="myForm.email2" placeholder="Email"


Set Value as:

 $scope.myForm.email2 = $scope.names[0].success;

Python mysqldb: Library not loaded: libmysqlclient.18.dylib

On new El Capitan installation where SIP(rootless prevents access to usr/lib/) is on by default and you cannot create the symlink unless you are in recovery mode. As @yannisxu said you can disable SIP and do your symlink to /usr/lib/local and this will work.

you can use the following command on MAC OSX El Capitan instead of turning off SIP:

sudo ln -s /usr/local/mysql/lib/libmysqlclient.18.dylib /usr/local/lib/libmysqlclient.18.dylib

There used to be an option where you can login as root and this can disable SIP but in the final release that is now obsolete, you can read more about it here:


There is a nvram boot-args command available in Developer Beta 1 which can disable SIP when run with root privileges:

nvram boot-args="rootless=0"

Will this option of disabling SIP also be available in the El Capitan release version? Or is this strictly for the Developer Builds?


This nvram boot-args command will be going away. It will not be available in the El Capitan release version and may disappear before the end of the Developer Betas. Keep an eye on the release notes for future Developer Betas.

Count number of rows within each group

The simple option to use with aggregate is the length function which will give you the length of the vector in the subset. Sometimes a little more robust is to use function(x) sum( ! ).

update package.json version automatically

As an addition to npm version you can use the --no-git-tag-version flag if you want a version bump but no tag or a new commit:

npm --no-git-tag-version version patch

how to update spyder on anaconda

One way to avoid errors during installing or updating packages is to run the Anaconda prompt as Administrator. Hope it helps!

detect key press in python?

As OP mention about raw_input - that means he want cli solution. Linux: curses is what you want (windows PDCurses). Curses, is an graphical API for cli software, you can achieve more than just detect key events.

This code will detect keys until new line is pressed.

import curses
import os

def main(win):
    win.addstr("Detected key:")
    while 1:          
           key = win.getkey()         
           win.addstr("Detected key:")
           if key == os.linesep:
        except Exception as e:
           # No input   


How to execute a bash command stored as a string with quotes and asterisk

Use an array, not a string, as given as guidance in BashFAQ #50.

Using a string is extremely bad security practice: Consider the case where password (or a where clause in the query, or any other component) is user-provided; you don't want to eval a password containing $(rm -rf .)!

Just Running A Local Command

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )

Printing Your Command Unambiguously

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
printf 'Proposing to run: '
printf '%q ' "${cmd[@]}"
printf '\n'

Running Your Command Over SSH (Method 1: Using Stdin)

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
printf -v cmd_str '%q ' "${cmd[@]}"
ssh other_host 'bash -s' <<<"$cmd_str"

Running Your Command Over SSH (Method 2: Command Line)

cmd=( mysql AMORE -u username -ppassword -h localhost -e "SELECT  host  FROM amoreconfig" )
printf -v cmd_str '%q ' "${cmd[@]}"
ssh other_host "bash -c $cmd_str"

Avoid browser popup blockers

Based on Jason Sebring's very useful tip, and on the stuff covered here and there, I found a perfect solution for my case:

Pseudo code with Javascript snippets:

  1. immediately create a blank popup on user action

     var importantStuff ='', '_blank');

    (Enrich the call to with whatever additional options you need.)

    Optional: add some "waiting" info message. Examples:

    a) An external HTML page: replace the above line with

     var importantStuff ='', '_blank');

    b) Text: add the following line below the above one:

     importantStuff.document.write('Loading preview...');
  2. fill it with content when ready (when the AJAX call is returned, for instance)

     importantStuff.location.href = '';

    Alternatively, you could close the window here if you don't need it after all (if ajax request fails, for example - thanks to @Goose for the comment):


I actually use this solution for a mailto redirection, and it works on all my browsers (windows 7, Android). The _blank bit helps for the mailto redirection to work on mobile, btw.

Is there an easy way to check the .NET Framework version?

Environment.Version() is giving the correct answer for a different question. The same version of the CLR is used in .NET 2.0, 3, and 3.5. I suppose you could check the GAC for libraries that were added in each of those subsequent releases.

What is the difference between Left, Right, Outer and Inner Joins?

Check out Join (SQL) on Wikipedia

  • Inner join - Given two tables an inner join returns all rows that exist in both tables
  • left / right (outer) join - Given two tables returns all rows that exist in either the left or right table of your join, plus the rows from the other side will be returned when the join clause is a match or null will be returned for those columns

  • Full Outer - Given two tables returns all rows, and will return nulls when either the left or right column is not there

  • Cross Joins - Cartesian join and can be dangerous if not used carefully

Is it possible to compile a program written in Python?

Python, as a dynamic language, cannot be "compiled" into machine code statically, like C or COBOL can. You'll always need an interpreter to execute the code, which, by definition in the language, is a dynamic operation.

You can "translate" source code in bytecode, which is just an intermediate process that the interpreter does to speed up the load of the code, It converts text files, with comments, blank spaces, words like 'if', 'def', 'in', etc in binary code, but the operations behind are exactly the same, in Python, not in machine code or any other language. This is what it's stored in .pyc files and it's also portable between architectures.

Probably what you need it's not "compile" the code (which it's not possible) but to "embed" an interpreter (in the right architecture) with the code to allow running the code without an external installation of the interpreter. To do that, you can use all those tools like py2exe or cx_Freeze.

Maybe I'm being a little pedantic on this :-P

setting y-axis limit in matplotlib

This worked at least in matplotlib version 2.2.2:

plt.axis([None, None, 0, 100])

Probably this is a nice way to set up for example xmin and ymax only, etc.

How can I print each command before executing?

set -x is fine.

Another way to print each executed command is to use trap with DEBUG. Put this line at the beginning of your script :

trap 'echo "# $BASH_COMMAND"' DEBUG

You can find a lot of other trap usages here.

Regarding C++ Include another class

you need to forward declare the name of the class if you don't want a header:

class ClassTwo;

Important: This only works in some cases, see Als's answer for more information..

Git pull a certain branch from GitHub

The best way is:

git checkout -b <new_branch> <remote repo name>/<new_branch>

mysql update multiple columns with same now()

You can put the following code on the default value of the timestamp column: CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, so on update the two columns take the same value.

Parsing JSON in Excel VBA

Another Regex based JSON parser (decode only)

Private Enum JsonStep
End Enum

Private regexp As Object

Private Function JsonStepName(ByVal json_step As JsonStep) As String
    Select Case json_step
        Case jsonString: JsonStepName = "'STRING'"
        Case jsonNumber: JsonStepName = "'NUMBER'"
        Case jsonTrue: JsonStepName = "true"
        Case jsonFalse: JsonStepName = "false"
        Case jsonNull: JsonStepName = "null"
        Case jsonOpeningBrace: JsonStepName = "'{'"
        Case jsonClosingBrace: JsonStepName = "'}'"
        Case jsonOpeningBracket: JsonStepName = "'['"
        Case jsonClosingBracket: JsonStepName = "']'"
        Case jsonComma: JsonStepName = "','"
        Case jsonColon: JsonStepName = "':'"
    End Select
End Function

Private Function Unescape(ByVal str As String) As String
    Dim match As Object

    str = Replace$(str, "\""", """")
    str = Replace$(str, "\\", "\")
    str = Replace$(str, "\/", "/")
    str = Replace$(str, "\b", vbBack)
    str = Replace$(str, "\f", vbFormFeed)
    str = Replace$(str, "\n", vbCrLf)
    str = Replace$(str, "\r", vbCr)
    str = Replace$(str, "\t", vbTab)
    With regexp
        .Global = True
        .IgnoreCase = False
        .MultiLine = False
        .Pattern = "\\u([0-9a-fA-F]{4})"
        For Each match In .Execute(str)
            str = Replace$(str, match.value, ChrW$(Val("&H" + match.SubMatches(0))), match.FirstIndex + 1, 1)
        Next match
    End With
    Unescape = str
End Function

Private Function ParseStep(ByVal str As String, _
                           ByRef index As Long, _
                           ByRef value As Variant, _
                           ByVal json_step As JsonStep, _
                           ByVal expected As Boolean) As Boolean
    Dim match As Object

    With regexp
        .Global = False
        .IgnoreCase = False
        .MultiLine = False
        Select Case json_step
            'Case jsonString: .Pattern = "^\s*""(([^\\""]+|\\[""\\/bfnrt]|\\u[0-9a-fA-F]{4})*)""\s*"
            Case jsonString: .Pattern = "^\s*""([^\\""]+|([^\\""]+|\\[""\\/bfnrt]|\\u[0-9a-fA-F]{4})*)""\s*"
            Case jsonNumber: .Pattern = "^\s*(-?(0|[1-9]\d*)(\.\d+)?([eE][-+]?\d+)?)\s*"
            Case jsonTrue: .Pattern = "^\s*(true)\s*"
            Case jsonFalse: .Pattern = "^\s*(false)\s*"
            Case jsonNull: .Pattern = "^\s*(null)\s*"
            Case jsonOpeningBrace: .Pattern = "^\s*(\{)\s*"
            Case jsonClosingBrace: .Pattern = "^\s*(\})\s*"
            Case jsonOpeningBracket: .Pattern = "^\s*(\[)\s*"
            Case jsonClosingBracket: .Pattern = "^\s*(\])\s*"
            Case jsonComma: .Pattern = "^\s*(\,)\s*"
            Case jsonColon: .Pattern = "^\s*(:)\s*"
        End Select
        Set match = .Execute(Mid$(str, index))
    End With
    If match.Count > 0 Then
        index = index + match(0).Length
        Select Case json_step
            Case jsonString
                If match(0).SubMatches(1) = Empty Then
                    value = match(0).SubMatches(0)
                    value = Unescape(match(0).SubMatches(0))
                End If
            Case jsonNumber: value = Val(match(0).SubMatches(0))
            Case jsonTrue: value = True
            Case jsonFalse: value = False
            Case jsonNull: value = Null
            Case Else: value = Empty
        End Select
        ParseStep = True
    ElseIf expected Then
        Err.Raise 10001, "ParseJson", "Expecting " & JsonStepName(json_step) & " at char " & index & "."
    End If
End Function

Private Function ParseValue(ByRef str As String, _
                            ByRef index As Long, _
                            ByRef value As Variant, _
                            ByVal expected As Boolean) As Boolean
    ParseValue = True
    If ParseStep(str, index, value, jsonString, False) Then Exit Function
    If ParseStep(str, index, value, jsonNumber, False) Then Exit Function
    If ParseObject(str, index, value, False) Then Exit Function
    If ParseArray(str, index, value, False) Then Exit Function
    If ParseStep(str, index, value, jsonTrue, False) Then Exit Function
    If ParseStep(str, index, value, jsonFalse, False) Then Exit Function
    If ParseStep(str, index, value, jsonNull, False) Then Exit Function
    ParseValue = False
    If expected Then
        Err.Raise 10001, "ParseJson", "Expecting " & JsonStepName(jsonString) & ", " & JsonStepName(jsonNumber) & ", " & JsonStepName(jsonTrue) & ", " & JsonStepName(jsonFalse) & ", " & JsonStepName(jsonNull) & ", " & JsonStepName(jsonOpeningBrace) & ", or " & JsonStepName(jsonOpeningBracket) & " at char " & index & "."
    End If
End Function

Private Function ParseObject(ByRef str As String, _
                             ByRef index As Long, _
                             ByRef obj As Variant, _
                             ByVal expected As Boolean) As Boolean
    Dim key As Variant
    Dim value As Variant

    ParseObject = ParseStep(str, index, Empty, jsonOpeningBrace, expected)
    If ParseObject Then
        Set obj = CreateObject("Scripting.Dictionary")
        If ParseStep(str, index, Empty, jsonClosingBrace, False) Then Exit Function
            If ParseStep(str, index, key, jsonString, True) Then
                If ParseStep(str, index, Empty, jsonColon, True) Then
                    If ParseValue(str, index, value, True) Then
                        If IsObject(value) Then
                            Set obj.Item(key) = value
                            obj.Item(key) = value
                        End If
                    End If
                End If
            End If
        Loop While ParseStep(str, index, Empty, jsonComma, False)
        ParseObject = ParseStep(str, index, Empty, jsonClosingBrace, True)
    End If
End Function

Private Function ParseArray(ByRef str As String, _
                            ByRef index As Long, _
                            ByRef arr As Variant, _
                            ByVal expected As Boolean) As Boolean
    Dim key As Variant
    Dim value As Variant

    ParseArray = ParseStep(str, index, Empty, jsonOpeningBracket, expected)
    If ParseArray Then
        Set arr = New Collection
        If ParseStep(str, index, Empty, jsonClosingBracket, False) Then Exit Function
            If ParseValue(str, index, value, True) Then
                arr.Add value
            End If
        Loop While ParseStep(str, index, Empty, jsonComma, False)
        ParseArray = ParseStep(str, index, Empty, jsonClosingBracket, True)
    End If
End Function

Public Function ParseJson(ByVal str As String) As Object
    If regexp Is Nothing Then
        Set regexp = CreateObject("VBScript.RegExp")
    End If
    If ParseObject(str, 1, ParseJson, False) Then Exit Function
    If ParseArray(str, 1, ParseJson, False) Then Exit Function
    Err.Raise 10001, "ParseJson", "Expecting " & JsonStepName(jsonOpeningBrace) & " or " & JsonStepName(jsonOpeningBracket) & "."
End Function