Programs & Examples On #Command execution

How to display a database table on to the table in the JSP page

The problem here is very simple. If you want to display value in JSP, you have to use <%= %> tag instead of <% %>, here is the solved code:

<tr> <td><%=rs.getInt("ID") %></td> <td><%=rs.getString("NAME") %></td> <td><%=rs.getString("SKILL") %></td> </tr>

load external css file in body tag

No, it is not okay to put a link element in the body tag. See the specification (links to the HTML4.01 specs, but I believe it is true for all versions of HTML):

“This element defines a link. Unlike A, it may only appear in the HEAD section of a document, although it may appear any number of times.”

Linux/Unix command to determine if process is running?

I use pgrep -l httpd but not sure it is present on any platform...
Who can confirm on OSX?

PHPmailer sending HTML CODE

do like this-paste your html code inside your separate html file using GET method.

    $mail->WordWrap = 70;                                 
    $mail->addAttachment= $_GET['addattachment']; $mail->AltBody   
    =$_GET['AltBody'];  $mail->Subject = $_GET['subject']; $mail->Body = $_GET['body'];

excel VBA run macro automatically whenever a cell is changed

I was creating a form in which the user enters an email address used by another macro to email a specific cell group to the address entered. I patched together this simple code from several sites and my limited knowledge of VBA. This simply watches for one cell (In my case K22) to be updated and then kills any hyperlink in that cell.

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim KeyCells As Range

    ' The variable KeyCells contains the cells that will
    ' cause an alert when they are changed.
    Set KeyCells = Range("K22")

    If Not Application.Intersect(KeyCells, Range(Target.Address)) _
           Is Nothing Then


    End If 
End Sub

Filter Pyspark dataframe column with None value

isNull()/isNotNull() will return the respective rows which have dt_mvmt as Null or !Null.

method_1 = df.filter(df['dt_mvmt'].isNotNull()).count()
method_2 = df.filter(df.dt_mvmt.isNotNull()).count()

Both will return the same result

How to "scan" a website (or page) for info, and bring it into my program?

This is referred to as screen scraping, wikipedia has this article on the more specific web scraping. It can be a major challenge because there's some ugly, mess-up, broken-if-not-for-browser-cleverness HTML out there, so good luck.

How to specify maven's distributionManagement organisation wide?

The best solution for this is to create a simple parent pom file project (with packaging 'pom') generically for all projects from your organization.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="" xmlns:xsi=""




This can be built, released, and deployed to your local nexus so everyone has access to its artifact.

Now for all projects which you wish to use it, simply include this section:


This solution will allow you to easily add other common things to all your company's projects. For instance if you wanted to standardize your JUnit usage to a specific version, this would be the perfect place for that.

If you have projects that use multi-module structures that have their own parent, Maven also supports chaining inheritance so it is perfectly acceptable to make your project's parent pom file refer to your company's parent pom and have the project's child modules not even aware of your company's parent.

I see from your example project structure that you are attempting to put your parent project at the same level as your aggregator pom. If your project needs its own parent, the best approach I have found is to include the parent at the same level as the rest of the modules and have your aggregator pom.xml file at the root of where all your modules' directories exist.

- pom.xml (aggregator)
    - project-parent
    - project-module1
    - project-module2

What you do with this structure is include your parent module in the aggregator and build everything with a mvn install from the root directory.

We use this exact solution at my organization and it has stood the test of time and worked quite well for us.

Choosing a file in Python with simple Dialog

Another option to consider is Zenity:

I had a situation where I was developing a Python server application (no GUI component) and hence didn't want to introduce a dependency on any python GUI toolkits, but I wanted some of my debug scripts to be parameterized by input files and wanted to visually prompt the user for a file if they didn't specify one on the command line. Zenity was a perfect fit. To achieve this, invoke "zenity --file-selection" using the subprocess module and capture the stdout. Of course this solution isn't Python-specific.

Zenity supports multiple platforms and happened to already be installed on our dev servers so it facilitated our debugging/development without introducing an unwanted dependency.

How to execute an oracle stored procedure?

Have you tried to correct the syntax like this?:

create or replace procedure temp_proc AS

Python reading from a file and saving to utf-8

You can also get through it by the code below:


How to capture no file for fs.readFileSync()?

Basically, fs.readFileSync throws an error when a file is not found. This error is from the Error prototype and thrown using throw, hence the only way to catch is with a try / catch block:

var fileContents;
try {
  fileContents = fs.readFileSync('');
} catch (err) {
  // Here you get the error when the file was not found,
  // but you also get any other error

Unfortunately you can not detect which error has been thrown just by looking at its prototype chain:

if (err instanceof Error)

is the best you can do, and this will be true for most (if not all) errors. Hence I'd suggest you go with the code property and check its value:

if (err.code === 'ENOENT') {
  console.log('File not found!');
} else {
  throw err;

This way, you deal only with this specific error and re-throw all other errors.

Alternatively, you can also access the error's message property to verify the detailed error message, which in this case is:

ENOENT, no such file or directory ''

Hope this helps.

Can I delete data from the iOS DeviceSupport directory?

The ~/Library/Developer/Xcode/iOS DeviceSupport folder is basically only needed to symbolicate crash logs.

You could completely purge the entire folder. Of course the next time you connect one of your devices, Xcode would redownload the symbol data from the device.

I clean out that folder once a year or so by deleting folders for versions of iOS I no longer support or expect to ever have to symbolicate a crash log for.

Error: Could not find or load main class

You must ensure that you add the location of your .class file to your classpath. So, if its in the current folder, add . to your classpath. Note that the Windows classpath separator is a semi-colon, i.e. a ;.

How to generate graphs and charts from mysql database in php

I use Google Chart Tools It's well documented and the charts look great. Being javascript, you can feed it json data via ajax.

bash script use cut command at variable and store result at another variable

The awk solution is what I would use, but if you want to understand your problems with bash, here is a revised version of your script.

#!/bin/bash -vx

##config file with ip addresses like

while read line ; do
  ##this line is not correct, should strip :port and store to ip var
  ip=$( echo "$line" |cut -d\: -f1 )
  ping $ip
done < ${file}

You could write your top line as

for line in $(cat $file) ; do ...

(but not recommended).

You needed command substitution $( ... ) to get the value assigned to $ip

reading lines from a file is usually considered more efficient with the while read line ... done < ${file} pattern.

I hope this helps.

Why Doesn't C# Allow Static Methods to Implement an Interface?

To the extent that interfaces represent "contracts", it seems quiet reasonable for static classes to implement interfaces.

The above arguments all seem to miss this point about contracts.

TypeError: Missing 1 required positional argument: 'self'

You can call the method like pump.getPumps(). By adding @classmethod decorator on the method. A class method receives the class as the implicit first argument, just like an instance method receives the instance.

class Pump:

def __init__(self):
    print ("init") # never prints

def getPumps(cls):
            # Open database connection
            # some stuff here that never gets executed because of error

So, simply call Pump.getPumps() .

In java, it is termed as static method.

How do I pass parameters into a PHP script through a webpage?

Presumably you're passing the arguments in on the command line as follows:

php /path/to/wwwpublic/path/to/script.php arg1 arg2

... and then accessing them in the script thusly:

// $argv[0] is '/path/to/wwwpublic/path/to/script.php'
$argument1 = $argv[1];
$argument2 = $argv[2];

What you need to be doing when passing arguments through HTTP (accessing the script over the web) is using the query string and access them through the $_GET superglobal:

Go to

... and access:

$argument1 = $_GET['argument1'];
$argument2 = $_GET['argument2'];

If you want the script to run regardless of where you call it from (command line or from the browser) you'll want something like the following:

EDIT: as pointed out by Cthulhu in the comments, the most direct way to test which environment you're executing in is to use the PHP_SAPI constant. I've updated the code accordingly:

if (PHP_SAPI === 'cli') {
    $argument1 = $argv[1];
    $argument2 = $argv[2];
else {
    $argument1 = $_GET['argument1'];
    $argument2 = $_GET['argument2'];

How to copy Outlook mail message into excel using VBA or Macros

Since you have not mentioned what needs to be copied, I have left that section empty in the code below.

Also you don't need to move the email to the folder first and then run the macro in that folder. You can run the macro on the incoming mail and then move it to the folder at the same time.

This will get you started. I have commented the code so that you will not face any problem understanding it.

First paste the below mentioned code in the outlook module.


  1. Click on Tools~~>Rules and Alerts
  2. Click on "New Rule"
  3. Click on "start from a blank rule"
  4. Select "Check messages When they arrive"
  5. Under conditions, click on "with specific words in the subject"
  6. Click on "specific words" under rules description.
  7. Type the word that you want to check in the dialog box that pops up and click on "add".
  8. Click "Ok" and click next
  9. Select "move it to specified folder" and also select "run a script" in the same box
  10. In the box below, specify the specific folder and also the script (the macro that you have in module) to run.
  11. Click on finish and you are done.

When the new email arrives not only will the email move to the folder that you specify but data from it will be exported to Excel as well.


Const xlUp As Long = -4162

Sub ExportToExcel(MyMail As MailItem)
    Dim strID As String, olNS As Outlook.Namespace
    Dim olMail As Outlook.MailItem
    Dim strFileName As String

    '~~> Excel Variables
    Dim oXLApp As Object, oXLwb As Object, oXLws As Object
    Dim lRow As Long

    strID = MyMail.EntryID
    Set olNS = Application.GetNamespace("MAPI")
    Set olMail = olNS.GetItemFromID(strID)

    '~~> Establish an EXCEL application object
    On Error Resume Next
    Set oXLApp = GetObject(, "Excel.Application")

    '~~> If not found then create new instance
    If Err.Number <> 0 Then
        Set oXLApp = CreateObject("Excel.Application")
    End If
    On Error GoTo 0

    '~~> Show Excel
    oXLApp.Visible = True

    '~~> Open the relevant file
    Set oXLwb = oXLApp.Workbooks.Open("C:\Sample.xls")

    '~~> Set the relevant output sheet. Change as applicable
    Set oXLws = oXLwb.Sheets("Sheet1")

    lRow = oXLws.Range("A" & oXLApp.Rows.Count).End(xlUp).Row + 1

    '~~> Write to outlook
    With oXLws
        '~~> Code here to output data from email to Excel File
        '~~> For example
        .Range("A" & lRow).Value = olMail.Subject
        .Range("B" & lRow).Value = olMail.SenderName
    End With

    '~~> Close and Clean up Excel
    oXLwb.Close (True)
    Set oXLws = Nothing
    Set oXLwb = Nothing
    Set oXLApp = Nothing

    Set olMail = Nothing
    Set olNS = Nothing
End Sub


To extract the contents from your email body, you can split it using SPLIT() and then parsing out the relevant information from it. See this example

Dim MyAr() As String

MyAr = Split(olMail.body, vbCrLf)

For i = LBound(MyAr) To UBound(MyAr)
    '~~> This will give you the contents of your email
    '~~> on separate lines
    Debug.Print MyAr(i)
Next i

How to add an ORDER BY clause using CodeIgniter's Active Record methods?

function getProductionGroupItems($itemId){

    /*********** order by *********** */
     $this->db->order_by("id", "asc");

         foreach($q->result() as $row){
         return $data;
    return false;

Adding click event handler to iframe

iframe doesn't have onclick event but we can implement this by using iframe's onload event and javascript like this...

function iframeclick() {
document.getElementById("theiframe").contentWindow.document.body.onclick = function() {

<iframe id="theiframe" src="youriframe.html" style="width: 100px; height: 100px;" onload="iframeclick()"></iframe>

I hope it will helpful to you....

What is Linux’s native GUI API?

In Linux the graphical user interface is not a part of the operating system. The graphical user interface found on most Linux desktops is provided by software called the X Window System, which defines a device independent way of dealing with screens, keyboards and pointer devices.

X Window defines a network protocol for communication, and any program that knows how to "speak" this protocol can use it. There is a C library called Xlib that makes it easier to use this protocol, so Xlib is kind of the native GUI API. Xlib is not the only way to access an X Window server; there is also XCB.

Toolkit libraries such as GTK+ (used by GNOME) and Qt (used by KDE), built on top of Xlib, are used because they are easier to program with. For example they give you a consistent look and feel across applications, make it easier to use drag-and-drop, provide components standard to a modern desktop environment, and so on.

How X draws on the screen internally depends on the implementation. has a device independent part and a device dependent part. The former manages screen resources such as windows, while the latter communicates with the graphics card driver, usually a kernel module. The communication may happen over direct memory access or through system calls to the kernel. The driver translates the commands into a form that the hardware on the card understands.

As of 2013, a new window system called Wayland is starting to become usable, and many distributions have said they will at some point migrate to it, though there is still no clear schedule. This system is based on OpenGL/ES API, which means that in the future OpenGL will be the "native GUI API" in Linux. Work is being done to port GTK+ and QT to Wayland, so that current popular applications and desktop systems would need minimal changes. The applications that cannot be ported will be supported through an X11 server, much like OS X supports X11 apps through Xquartz. The GTK+ port is expected to be finished within a year, while Qt 5 already has complete Wayland support.

To further complicate matters, Ubuntu has announced they are developing a new system called Mir because of problems they perceive with Wayland. This window system is also based on the OpenGL/ES API.

How to write a simple Java program that finds the greatest common divisor between two numbers?

Now, I just started programing about a week ago, so nothing fancy, but I had this as a problem and came up with this, which may be easier for people who are just getting into programing to understand. It uses Euclid's method like in previous examples.

public class GCD {
  public static void main(String[] args){
    int x = Math.max(Integer.parseInt(args[0]),Integer.parseInt(args[1]));    
    int y = Math.min(Integer.parseInt(args[0]),Integer.parseInt(args[1]));     
    for (int r = x % y; r != 0; r = x % y){
      x = y;
      y = r;

'Invalid update: invalid number of rows in section 0

Here is some code from above added with actual action code (point 1 and 2);

func tableView(_ tableView: UITableView, trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration? {
    let deleteAction = UIContextualAction(style: .destructive, title: "Delete") { _, _, completionHandler in

        // 1. remove object from your array
        scannedItems.remove(at: indexPath.row)
        // 2. reload the table, otherwise you get an index out of bounds crash

    deleteAction.backgroundColor = .systemOrange
    let configuration = UISwipeActionsConfiguration(actions: [deleteAction])
    configuration.performsFirstActionWithFullSwipe = true
    return configuration

HTML - How to do a Confirmation popup to a Submit button and then send the request?

The most compact version:

<input type="submit" onclick="return confirm('Are you sure?')" />

The key thing to note is the return


Because there are many ways to skin a cat, here is another alternate method:


<input type="submit" onclick="clicked(event)" />


function clicked(e)
    if(!confirm('Are you sure?')) {

Showing line numbers in IPython/Jupyter Notebooks

You can also find Toggle Line Numbers under View on the top toolbar of the Jupyter notebook in your browser. This adds/removes the lines numbers in all notebook cells.

For me, Esc+l only added/removed the line numbers of the active cell.

MySQL count occurrences greater than 2

SELECT count(word) as count 
FROM words 
HAVING count >= 2;

When to use MyISAM and InnoDB?

Read about Storage Engines.


The MyISAM storage engine in MySQL.

  • Simpler to design and create, thus better for beginners. No worries about the foreign relationships between tables.
  • Faster than InnoDB on the whole as a result of the simpler structure thus much less costs of server resources. -- Mostly no longer true.
  • Full-text indexing. -- InnoDB has it now
  • Especially good for read-intensive (select) tables. -- Mostly no longer true.
  • Disk footprint is 2x-3x less than InnoDB's. -- As of Version 5.7, this is perhaps the only real advantage of MyISAM.


The InnoDB storage engine in MySQL.

  • Support for transactions (giving you support for the ACID property).
  • Row-level locking. Having a more fine grained locking-mechanism gives you higher concurrency compared to, for instance, MyISAM.
  • Foreign key constraints. Allowing you to let the database ensure the integrity of the state of the database, and the relationships between tables.
  • InnoDB is more resistant to table corruption than MyISAM.
  • Support for large buffer pool for both data and indexes. MyISAM key buffer is only for indexes.
  • MyISAM is stagnant; all future enhancements will be in InnoDB. This was made abundantly clear with the roll out of Version 8.0.

MyISAM Limitations:

  • No foreign keys and cascading deletes/updates
  • No transactional integrity (ACID compliance)
  • No rollback abilities
  • 4,284,867,296 row limit (2^32) -- This is old default. The configurable limit (for many versions) has been 2**56 bytes.
  • Maximum of 64 indexes per table

InnoDB Limitations:

  • No full text indexing (Below-5.6 mysql version)
  • Cannot be compressed for fast, read-only (5.5.14 introduced ROW_FORMAT=COMPRESSED)
  • You cannot repair an InnoDB table

For brief understanding read below links:

  1. MySQL Engines: InnoDB vs. MyISAM – A Comparison of Pros and Cons
  2. MySQL Engines: MyISAM vs. InnoDB
  3. What are the main differences between InnoDB and MyISAM?
  4. MyISAM versus InnoDB
  5. What's the difference between MyISAM and InnoDB?
  6. MySql: MyISAM vs. Inno DB!

How to unescape a Java string literal in Java?

org.apache.commons.lang3.StringEscapeUtils from commons-lang3 is marked deprecated now. You can use org.apache.commons.text.StringEscapeUtils#unescapeJava(String) instead. It requires an additional Maven dependency:


and seems to handle some more special cases, it e.g. unescapes:

  • escaped backslashes, single and double quotes
  • escaped octal and unicode values
  • \\b, \\n, \\t, \\f, \\r

How to prevent Browser cache for php site

Prevent browser cache is not a good idea depending on the case. Looking for a solution I found solutions like this:

<link rel="stylesheet" type="text/css" href="meu.css?v=<?=filemtime($file);?>">

the problem here is that if the file is overwritten during an update on the server, which is my scenario, the cache is ignored because timestamp is modified even the content of the file is the same.

I use this solution to force browser to download assets only if its content is modified:

<link rel="stylesheet" type="text/css" href="meu.css?v=<?=hash_file('md5', $file);?>">

Defining a HTML template to append using JQuery

Very good answer from DevWL about using the native HTML5 template element. To contribute to this good question from the OP I would like to add on how to use this template element using jQuery, for example:

$($('template').html()).insertAfter( $('#somewhere_else') );

The content of the template is not html, but just treated as data, so you need to wrap the content into a jQuery object to then access jQuery's methods.

how concatenate two variables in batch script?

Enabling delayed variable expansion solves you problem, the script produces "hi":

setlocal EnableDelayedExpansion

set var1=A
set var2=B

set AB=hi

set newvar=!%var1%%var2%!

echo %newvar%

String concatenation: concat() vs "+" operator

No, not quite.

Firstly, there's a slight difference in semantics. If a is null, then a.concat(b) throws a NullPointerException but a+=b will treat the original value of a as if it were null. Furthermore, the concat() method only accepts String values while the + operator will silently convert the argument to a String (using the toString() method for objects). So the concat() method is more strict in what it accepts.

To look under the hood, write a simple class with a += b;

public class Concat {
    String cat(String a, String b) {
        a += b;
        return a;

Now disassemble with javap -c (included in the Sun JDK). You should see a listing including:

java.lang.String cat(java.lang.String, java.lang.String);
   0:   new     #2; //class java/lang/StringBuilder
   3:   dup
   4:   invokespecial   #3; //Method java/lang/StringBuilder."<init>":()V
   7:   aload_1
   8:   invokevirtual   #4; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
   11:  aload_2
   12:  invokevirtual   #4; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
   15:  invokevirtual   #5; //Method java/lang/StringBuilder.toString:()Ljava/lang/    String;
   18:  astore_1
   19:  aload_1
   20:  areturn

So, a += b is the equivalent of

a = new StringBuilder()

The concat method should be faster. However, with more strings the StringBuilder method wins, at least in terms of performance.

The source code of String and StringBuilder (and its package-private base class) is available in of the Sun JDK. You can see that you are building up a char array (resizing as necessary) and then throwing it away when you create the final String. In practice memory allocation is surprisingly fast.

Update: As Pawel Adamski notes, performance has changed in more recent HotSpot. javac still produces exactly the same code, but the bytecode compiler cheats. Simple testing entirely fails because the entire body of code is thrown away. Summing System.identityHashCode (not String.hashCode) shows the StringBuffer code has a slight advantage. Subject to change when the next update is released, or if you use a different JVM. From @lukaseder, a list of HotSpot JVM intrinsics.

How to find Max Date in List<Object>?

Just use Kotlin!

val list = listOf(user1, user2, user3)
val maxDate = list.maxBy { }?.date

How to disable "prevent this page from creating additional dialogs"?

function alertWithoutNotice(message){
    }, 1000);

How do I escape a reserved word in Oracle?

you have to rename the column to an other name because TABLE is reserved by Oracle.

You can see all reserved words of Oracle in the oracle view V$RESERVED_WORDS.

How do I show multiple recaptchas on a single page?

I would use invisible recaptcha. Then on your button use a tag like " formname='yourformname' " to specify which form is to be submitted and hide a submit form input.

The advantage of this is it allows for you to keep the html5 form validation intact, one recaptcha, but multiple button interfaces. Just capture the "captcha" input value for the token key generated by recaptcha.

<script src="" async defer ></script>

<div class="g-recaptcha" data-sitekey="yours" data-callback="onSubmit" data-size="invisible"></div>
var formanme = ''
$('button').on('click', function () { formname = '#'+$(this).attr('formname');
    if ( $(formname)[0].checkValidity() == true) { grecaptcha.execute(); }
    else { $(formname).find('input[type="submit"]').click() }

var onSubmit = function(token) {
    $(formname).append("<input type='hidden' name='captcha' value='"+token+"' />");

I find this FAR simpler and easier to manage.

fcntl substitute on Windows

The substitute of fcntl on windows are win32api calls. The usage is completely different. It is not some switch you can just flip.

In other words, porting a fcntl-heavy-user module to windows is not trivial. It requires you to analyze what exactly each fcntl call does and then find the equivalent win32api code, if any.

There's also the possibility that some code using fcntl has no windows equivalent, which would require you to change the module api and maybe the structure/paradigm of the program using the module you're porting.

If you provide more details about the fcntl calls people can find windows equivalents.

How do I strip all spaces out of a string in PHP?

Do you just mean spaces or all whitespace?

For just spaces, use str_replace:

$string = str_replace(' ', '', $string);

For all whitespace (including tabs and line ends), use preg_replace:

$string = preg_replace('/\s+/', '', $string);

(From here).

Auto-Submit Form using JavaScript

Try this,

HtmlElement head = _windowManager.ActiveBrowser.Document.GetElementsByTagName("head")[0];
HtmlElement scriptEl = _windowManager.ActiveBrowser.Document.CreateElement("script");
IHTMLScriptElement element = (IHTMLScriptElement)scriptEl.DomElement;
element.text = "window.onload = function() { document.forms[0].submit(); }";
strAdditionalHeader = "";

Understanding the Linux oom-killer's logs

This webpage have an explanation and a solution.

The solution is:

To fix this problem the behavior of the kernel has to be changed, so it will no longer overcommit the memory for application requests. Finally I have included those mentioned values into the /etc/sysctl.conf file, so they get automatically applied on start-up:

vm.overcommit_memory = 2

vm.overcommit_ratio = 80

How to find out the username and password for mysql database

There are two easy ways:

  1. In your cpanel Go to cpanel/ softaculous/ wordpress, under the current installation, you will see the websites you have installed with the wordpress. Click the "edit detail" of the particular website and you will see your SQL database username and password.

  2. In your server Access your FTP and view the wp-config.php

SQL select join: is it possible to prefix all columns as 'prefix.*'?

It seems the answer to your question is no, however one hack you can use is to assign a dummy column to separate each new table. This works especially well if you're looping through a result set for a list of columns in a scripting language such as Python or PHP.

SELECT '' as table1_dummy, table1.*, '' as table2_dummy, table2.*, '' as table3_dummy, table3.* FROM table1
JOIN table2 ON table2.table1id =
JOIN table3 ON table3.table1id =

I realize this doesn't answer your question exactly, but if you're a coder this is a great way to separate tables with duplicate column names. Hope this helps somebody.

How to change status bar color in Flutter?

I can't comment directly in the thread since I don't have the requisite reputation yet, but the author asked the following:

the only issue is that the background is white but the clock, wireless and other text and icons are also in white .. I am not sure why!!

For anyone else who comes to this thread, here's what worked for me. The text color of the status bar is decided by the Brightness constant in flutter/material.dart. To change this, adjust the SystemChrome solution like so to configure the text:

      statusBarBrightness: Brightness.dark,

Your possible values for Brightness are Brightness.dark and Brightness.light.


Flatten List in LINQ

Try SelectMany()

var result = iList.SelectMany( i => i );

What is compiler, linker, loader?

  • Compiler: A language translator that converts a complete program into machine language to produce a program that the computer can process in its entirety.
  • Linker: Utility program which takes one or more compiled object files and combines them into an executable file or another object file.
  • Loader: loads the executable code into memory ,creates the program and data stack , initializes the registers and starts the code running.

Order by multiple columns with Doctrine

In Doctrine 2.x you can't pass multiple order by using doctrine 'orderBy' or 'addOrderBy' as above examples. Because, it automatically adds the 'ASC' at the end of the last column name when you left the second parameter blank, such as in the 'orderBy' function.

For an example ->orderBy('a.fist_name ASC, a.last_name ASC') will output SQL something like this 'ORDER BY first_name ASC, last_name ASC ASC'. So this is SQL syntax error. Simply because default of the orderBy or addOrderBy is 'ASC'.

To add multiple order by's you need to use 'add' function. And it will be like this.

->add('orderBy','first_name ASC, last_name ASC'). This will give you the correctly formatted SQL.

More info on add() function.

Hope this helps. Cheers!

mongodb count num of distinct values per field/key

Here is example of using aggregation API. To complicate the case we're grouping by case-insensitive words from array property of the document.

        $match: {
            keywords: { $not: {$size: 0} }
    { $unwind: "$keywords" },
        $group: {
            _id: {$toLower: '$keywords'},
            count: { $sum: 1 }
        $match: {
            count: { $gte: 2 }
    { $sort : { count : -1} },
    { $limit : 100 }

that give result such as

{ "_id" : "inflammation", "count" : 765 }
{ "_id" : "obesity", "count" : 641 }
{ "_id" : "epidemiology", "count" : 617 }
{ "_id" : "cancer", "count" : 604 }
{ "_id" : "breast cancer", "count" : 596 }
{ "_id" : "apoptosis", "count" : 570 }
{ "_id" : "children", "count" : 487 }
{ "_id" : "depression", "count" : 474 }
{ "_id" : "hiv", "count" : 468 }
{ "_id" : "prognosis", "count" : 428 }

Disable/Enable button in Excel/VBA

The following works for me (Excel 2010)

Dim b1 As Button

Set b1 = ActiveSheet.Buttons("Button 1")

b1.Font.ColorIndex = 15
b1.Enabled = False
Application.Cursor = xlWait
Call aLongAction
b1.Enabled = True
b1.Font.ColorIndex = 1
Application.Cursor = xlDefault

Be aware that .enabled = False does not gray out a button.

The font color has to be set explicitely to get it grayed.

SQL datetime format to date only

After perusing your previous questions I eventually determined you are probably on SQL Server 2005. For US format you would use style 101

select Subject, 
       CONVERT(varchar,DeliveryDate,101) as DeliveryDate
from Email_Administration 
where MerchantId =@MerchantID 

Java NIO FileChannel versus FileOutputstream performance / usefulness

I tested the performance of FileInputStream vs. FileChannel for decoding base64 encoded files. In my experients I tested rather large file and traditional io was alway a bit faster than nio.

FileChannel might have had an advantage in prior versions of the jvm because of synchonization overhead in several io related classes, but modern jvm are pretty good at removing unneeded locks.

How to return value from an asynchronous callback function?

If you happen to be using jQuery, you might want to give this a shot:

It allows you to defer the execution of your callback function until the ajax request (or any async operation) is completed. This can also be used to call a callback once several ajax requests have all completed.

"Bitmap too large to be uploaded into a texture"

As pointed by Larcho, starting from API level 10, you can use BitmapRegionDecoder to load specific regions from an image and with that, you can accomplish to show a large image in high resolution by allocating in memory just the needed regions. I've recently developed a lib that provides the visualisation of large images with touch gesture handling. The source code and samples are available here.

Why do I need an IoC container as opposed to straightforward DI code?

You don't need an IoC container.

But if you're rigorously following a DI pattern, you'll find that having one will remove a ton of redundant, boring code.

That's often the best time to use a library/framework, anyway - when you understand what it's doing and could do it without the library.

Iterating through all the cells in Excel VBA or VSTO 2005

You can use a For Each to iterate through all the cells in a defined range.

Public Sub IterateThroughRange()

Dim wb As Workbook
Dim ws As Worksheet
Dim rng As Range
Dim cell As Range

Set wb = Application.Workbooks(1)
Set ws = wb.Sheets(1)
Set rng = ws.Range("A1", "C3")

For Each cell In rng.Cells
    cell.Value = cell.Address
Next cell

End Sub

Adding images to an HTML document with javascript

With a little research i found that javascript does not know that a Document Object Exist unless the Object has Already loaded before the script code (As javascript reads down a page).

    <script type="text/javascript">
        function insert(){
            var src = document.getElementById("gamediv");
            var img = document.createElement("img");
            img.src = "img/eqp/"+this.apparel+"/"+this.facing+"_idle.png";
     <div id="gamediv">
         <script type="text/javascript">

Read a text file in R line by line

I suggest you check out chunked and disk.frame. They both have functions for reading in CSVs chunk-by-chunk.

In particular, disk.frame::csv_to_disk.frame may be the function you are after?

Execute php file from another php

It's trying to run it as a shell script, which interprets your <?php token as bash, which is a syntax error. Just use include() or one of its friends:

For example, in a.php put:

print "one";
include 'b.php';
print "three";

In b.php put:

print "two";


eric@dev ~ $ php a.php

How to convert all tables in database to one collation?

Following on from G H I've added the user and host parameters incase you need to do this on a remote server


    # <database> <user> <password> [<host> <charset> <collation>]
    # changes MySQL/MariaDB charset and collation for one database - all tables and
    # all columns in all tables


    [ -n "$DB" ] || exit 1
    [ -n "$USER" ] || exit 1
    [ -n "$PW" ] || exit 1
    [ -n "$HOST" ] || HOST="localhost"
    [ -n "$CHARSET" ] || CHARSET="utf8mb4"
    [ -n "$COLL" ] || COLL="utf8mb4_general_ci"


    echo $DB

    echo "USE $DB; SHOW TABLES;" | mysql  "$HOST" "$USER" "$PW" | (
        while read TABLE; do
            echo $DB.$TABLE


How to create a new branch from a tag?

If you simply want to create a new branch without immediately changing to it, you could do the following:

git branch newbranch v1.0

How can I fix assembly version conflicts with JSON.NET after updating NuGet package references in a new ASP.NET MVC 5 project?

I had similar issue and just wanted to post an answer for others in my situation.

I have a solution running a ASP.NET Web Application with multiple other C# class lib projects.

My ASP.NET Web Application wasn't using json, but other projects where.

This is how I fixed it:

  1. I made sure all projects where using latest version (6) using NuGet Update on all projects currently using any version of json - this didn't fix the issue
  2. I added json to the web application using NuGet - this fixed the issue (let me dive into why):

Step 2 was first of all adding a configuration information for json, that suggest that all projects, use the latest version (6) no matter what version they have. Adding the assembly binding to Web.Config is most likely the fix.

However, step 2 also cleaned up som legacy code. It turned out we have previously used an old version (5) of json in our Web Application and the NuGet folders wasn't deleted when the reference was (I suspect: manually) removed. Adding the latest json (6), removed the old folders (json v5). This might be part of the fix as well.

How can I refresh c# dataGridView after update ?

I don't know if this has really been solved or not... but by looking at all the other answers, nothing seems quite clear. The best way I found to do this is to put the same code, that was used to populate your datagridview into a method and pass it your form's datagridview, as so:

public void ConnectAndPopulateDataGridView(DataGridView dataGridView)
{ }

The code within the method is the exact same as the code used to populate the datagirdview originally, except for the datagridview name changing to whatever you called it in your method.

Now this method is called in your parent form.

The child form is launched via a .ShowDialog() then the method is called after so that it is called right after the child for is closed... as so:



Java 256-bit AES Password-Based Encryption

Share the password (a char[]) and salt (a byte[]—8 bytes selected by a SecureRandom makes a good salt—which doesn't need to be kept secret) with the recipient out-of-band. Then to derive a good key from this information:

/* Derive the key, given password and salt. */
SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA256");
KeySpec spec = new PBEKeySpec(password, salt, 65536, 256);
SecretKey tmp = factory.generateSecret(spec);
SecretKey secret = new SecretKeySpec(tmp.getEncoded(), "AES");

The magic numbers (which could be defined as constants somewhere) 65536 and 256 are the key derivation iteration count and the key size, respectively.

The key derivation function is iterated to require significant computational effort, and that prevents attackers from quickly trying many different passwords. The iteration count can be changed depending on the computing resources available.

The key size can be reduced to 128 bits, which is still considered "strong" encryption, but it doesn't give much of a safety margin if attacks are discovered that weaken AES.

Used with a proper block-chaining mode, the same derived key can be used to encrypt many messages. In Cipher Block Chaining (CBC), a random initialization vector (IV) is generated for each message, yielding different cipher text even if the plain text is identical. CBC may not be the most secure mode available to you (see AEAD below); there are many other modes with different security properties, but they all use a similar random input. In any case, the outputs of each encryption operation are the cipher text and the initialization vector:

/* Encrypt the message. */
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secret);
AlgorithmParameters params = cipher.getParameters();
byte[] iv = params.getParameterSpec(IvParameterSpec.class).getIV();
byte[] ciphertext = cipher.doFinal("Hello, World!".getBytes(StandardCharsets.UTF_8));

Store the ciphertext and the iv. On decryption, the SecretKey is regenerated in exactly the same way, using using the password with the same salt and iteration parameters. Initialize the cipher with this key and the initialization vector stored with the message:

/* Decrypt the message, given derived key and initialization vector. */
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, secret, new IvParameterSpec(iv));
String plaintext = new String(cipher.doFinal(ciphertext), StandardCharsets.UTF_8);

Java 7 included API support for AEAD cipher modes, and the "SunJCE" provider included with OpenJDK and Oracle distributions implements these beginning with Java 8. One of these modes is strongly recommended in place of CBC; it will protect the integrity of the data as well as their privacy.

A with the message "Illegal key size or default parameters" means that the cryptography strength is limited; the unlimited strength jurisdiction policy files are not in the correct location. In a JDK, they should be placed under ${jdk}/jre/lib/security

Based on the problem description, it sounds like the policy files are not correctly installed. Systems can easily have multiple Java runtimes; double-check to make sure that the correct location is being used.

How to export a CSV to Excel using Powershell

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

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

How to split a python string on new line characters

? Splitting line in Python:

Have you tried using str.splitlines() method?:

From the docs:


Return a list of the lines in the string, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true.

For example:

>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()
['Line 1', '', 'Line 3', 'Line 4']

>>> 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines(True)
['Line 1\n', '\n', 'Line 3\r', 'Line 4\r\n']

Which delimiters are considered?

This method uses the universal newlines approach to splitting lines.

The main difference between Python 2.X and Python 3.X is that the former uses the universal newlines approach to splitting lines, so "\r", "\n", and "\r\n" are considered line boundaries for 8-bit strings, while the latter uses a superset of it that also includes:

  • \v or \x0b: Line Tabulation (added in Python 3.2).
  • \f or \x0c: Form Feed (added in Python 3.2).
  • \x1c: File Separator.
  • \x1d: Group Separator.
  • \x1e: Record Separator.
  • \x85: Next Line (C1 Control Code).
  • \u2028: Line Separator.
  • \u2029: Paragraph Separator.

splitlines VS split:

Unlike str.split() when a delimiter string sep is given, this method returns an empty list for the empty string, and a terminal line break does not result in an extra line:

>>> ''.splitlines()

>>> 'Line 1\n'.splitlines()
['Line 1']

While str.split('\n') returns:

>>> ''.split('\n')

>>> 'Line 1\n'.split('\n')
['Line 1', '']

?? Removing additional whitespace:

If you also need to remove additional leading or trailing whitespace, like spaces, that are ignored by str.splitlines(), you could use str.splitlines() together with str.strip():

>>> [str.strip() for str in 'Line 1  \n  \nLine 3 \rLine 4 \r\n'.splitlines()]
['Line 1', '', 'Line 3', 'Line 4']

? Removing empty strings (''):

Lastly, if you want to filter out the empty strings from the resulting list, you could use filter():

>>> # Python 2.X:
>>> filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines())
['Line 1', 'Line 3', 'Line 4']

>>> # Python 3.X:
>>> list(filter(bool, 'Line 1\n\nLine 3\rLine 4\r\n'.splitlines()))
['Line 1', 'Line 3', 'Line 4']

Additional comment regarding the original question:

As the error you posted indicates and Burhan suggested, the problem is from the print. There's a related question about that could be useful to you: UnicodeEncodeError: 'charmap' codec can't encode - character maps to <undefined>, print function

What to put in a python module docstring?

To quote the specifications:

The docstring of a script (a stand-alone program) should be usable as its "usage" message, printed when the script is invoked with incorrect or missing arguments (or perhaps with a "-h" option, for "help"). Such a docstring should document the script's function and command line syntax, environment variables, and files. Usage messages can be fairly elaborate (several screens full) and should be sufficient for a new user to use the command properly, as well as a complete quick reference to all options and arguments for the sophisticated user.

The docstring for a module should generally list the classes, exceptions and functions (and any other objects) that are exported by the module, with a one-line summary of each. (These summaries generally give less detail than the summary line in the object's docstring.) The docstring for a package (i.e., the docstring of the package's module) should also list the modules and subpackages exported by the package.

The docstring for a class should summarize its behavior and list the public methods and instance variables. If the class is intended to be subclassed, and has an additional interface for subclasses, this interface should be listed separately (in the docstring). The class constructor should be documented in the docstring for its __init__ method. Individual methods should be documented by their own docstring.

The docstring of a function or method is a phrase ending in a period. It prescribes the function or method's effect as a command ("Do this", "Return that"), not as a description; e.g. don't write "Returns the pathname ...". A multiline-docstring for a function or method should summarize its behavior and document its arguments, return value(s), side effects, exceptions raised, and restrictions on when it can be called (all if applicable). Optional arguments should be indicated. It should be documented whether keyword arguments are part of the interface.

How to solve "Kernel panic - not syncing - Attempted to kill init" -- without erasing any user data

I just came across this problem when I replaced a failing disk. I had copied over the system files to the new disk, and was good about replacing the old disk's UUID entry with the new disk's UUID in fstab.

However I had not replaced the UUID in the grub.conf (sometimes menu.lst) file in /boot/grub. So check your grub.conf file, and if the "kernel" line has something like

kernel ... root=UUID=906eaa97-f66a-4d39-a39d-5091c7095987 

it likely has the old disk's UUID. Replace it with the new disk's UUID and run grub-install (if you're in a live CD rescue you may need to chroot or specify the grub directory).

PHP: Limit foreach() statement?

You can either use



foreach() if ($tmp++ < 2) {

(the second solution is even worse)

How can I sort generic list DESC and ASC?

Very simple way to sort List with int values in Descending order:

li.Sort((a,b)=> b-a);

Hope that this helps!

How to create a GUID in Excel?

I am using the following function in v.2013 excel vba macro code

Public Function GetGUID() As String 
    GetGUID = Mid$(CreateObject("Scriptlet.TypeLib").GUID, 2, 36) 
End Function 

Highlight label if checkbox is checked

This is an example of using the :checked pseudo-class to make forms more accessible. The :checked pseudo-class can be used with hidden inputs and their visible labels to build interactive widgets, such as image galleries. I created the snipped for the people that wanna test.

input[type=checkbox] + label {_x000D_
  color: #ccc;_x000D_
  font-style: italic;_x000D_
} _x000D_
input[type=checkbox]:checked + label {_x000D_
  color: #f00;_x000D_
  font-style: normal;_x000D_
<input type="checkbox" id="cb_name" name="cb_name"> _x000D_
<label for="cb_name">CSS is Awesome</label> 

How To Remove Outline Border From Input Button

using outline:none; we can remove that border in chrome

    border: none;

Uncaught TypeError: (intermediate value)(...) is not a function

  **Error Case:**

var handler = function(parameters) {

(function() {     //IIFE
 // some code

Output: TypeError: (intermediate value)(intermediate value) is not a function *How to Fix IT -> because you are missing semi colan(;) to separate expressions;


var handler = function(parameters) {
}; // <--- Add this semicolon(if you miss that semi colan .. 
   //error will occurs )

(function() {     //IIFE
 // some code

why this error comes?? Reason : specific rules for automatic semicolon insertion which is given ES6 stanards

How do I get JSON data from RESTful service using Python?

If you desire to use Python 3, you can use the following:

import json
import urllib.request
req = urllib.request.Request('url')
with urllib.request.urlopen(req) as response:
    result = json.loads(response.readall().decode('utf-8'))

console.log timestamps in Chrome?

I originally added this as a comment, but I wanted to add a screenshot as at least one person could not find the option (or maybe it was not available in their particular version for some reason).

On Chrome 68.0.3440.106 (and now checked in 72.0.3626.121) I had to

  • open dev tools (F12)
  • click the three-dot menu in the top right
  • click settings
  • select Preferences in the left menu
  • check show timestamps in the Console section of the settings screen

Settings > Preferences > Console > Show timestamps

checking if number entered is a digit in jquery

Forget regular expressions. JavaScript has a builtin function for this: isNaN():

isNaN(123)           // false
isNaN(-1.23)         // false
isNaN(5-2)           // false
isNaN(0)             // false
isNaN("100")         // false
isNaN("Hello")       // true
isNaN("2005/12/12")  // true

Just call it like so:

if (isNaN( $("#whatever").val() )) {
    // It isn't a number
} else {
    // It is a number

Why do I get a "permission denied" error while installing a gem?

Seems like a permissions issue. This is what worked for me

sudo chown -R $(whoami) /Library/Ruby/Gems/*

or in your case

sudo chown -R $(whoami) /usr/local/lib/ruby/gems/2.0.0/gems/

What does this do:

This is telling the system to change the files to change the ownership to the current user. Something must have gotten messed up when something got installed. Usually this is because there are multiple accounts or users are using sudo to install when they should not always have to.

Symfony - generate url with parameter in controller

make sure your controller extends Symfony\Bundle\FrameworkBundle\Controller\Controller;

you should also check app/console debug:router in terminal to see what name symfony has named the route

in my case it used a minus instead of an underscore

i.e blog-show

$uri = $this->generateUrl('blog-show', ['slug' => 'my-blog-post']);

Find an item in List by LINQ?

If it really is a List<string> you don't need LINQ, just use:

int GetItemIndex(string search)
    return _list == null ? -1 : _list.IndexOf(search);

If you are looking for the item itself, try:

string GetItem(string search)
    return _list == null ? null : _list.FirstOrDefault(s => s.Equals(search));

Last element in .each() set

For future Googlers i've a different approach to check if it's last element. It's similar to last lines in OP question.

This directly compares elements rather than just checking index numbers.

$yourset.each(function() {
    var $this = $(this);
    if($this[0] === $yourset.last()[0]) {
        //$this is the last one

Convert Mat to Array/Vector in OpenCV

None of the provided examples here work for the generic case, which are N dimensional matrices. Anything using "rows" assumes theres columns and rows only, a 4 dimensional matrix might have more.

Here is some example code copying a non-continuous N-dimensional matrix into a continuous memory stream - then converts it back into a Cv::Mat

#include <iostream>
#include <cstdint>
#include <cstring>
#include <opencv2/opencv.hpp>

int main(int argc, char**argv)
    if ( argc != 2 )
        std::cerr << "Usage: " << argv[0] << " <Image_Path>\n";
        return -1;
    cv::Mat origSource = cv::imread(argv[1],1);

    if (! {
        std::cerr << "Can't read image";
        return -1;

    // this will select a subsection of the original source image - WITHOUT copying the data
    // (the header will point to a region of interest, adjusting data pointers and row step sizes)
    cv::Mat sourceMat = origSource(cv::Range(origSource.size[0]/4,(3*origSource.size[0])/4),cv::Range(origSource.size[1]/4,(3*origSource.size[1])/4));

    // correctly copy the contents of an N dimensional cv::Mat
    // works just as fast as copying a 2D mat, but has much more difficult to read code :)
    // see
    // copy this code in your own cvMat_To_Char_Array() function which really OpenCV should provide somehow...
    // keep in mind that even Mat::clone() aligns each row at a 4 byte boundary, so uneven sized images always have stepgaps
    size_t totalsize = sourceMat.step[sourceMat.dims-1];
    const size_t rowsize = sourceMat.step[sourceMat.dims-1] * sourceMat.size[sourceMat.dims-1];
    size_t coordinates[sourceMat.dims-1] = {0};
    std::cout << "Image dimensions: ";
    for (int t=0;t<sourceMat.dims;t++)
        // calculate total size of multi dimensional matrix by multiplying dimensions
        std::cout << (t>0?" X ":"") << sourceMat.size[t];
    // Allocate destination image buffer
    uint8_t * imagebuffer = new uint8_t[totalsize];
    size_t srcptr=0,dptr=0;
    std::cout << std::endl;
    std::cout << "One pixel in image has " << sourceMat.step[sourceMat.dims-1] << " bytes" <<std::endl;
    std::cout << "Copying data in blocks of " << rowsize << " bytes" << std::endl ;
    std::cout << "Total size is " << totalsize << " bytes" << std::endl;
    while (dptr<totalsize) {
        // we copy entire rows at once, so lowest iterator is always [dims-2]
        // this is legal since OpenCV does not use 1 dimensional matrices internally (a 1D matrix is a 2d matrix with only 1 row)
        // destination matrix has no gaps so rows follow each other directly
        dptr += rowsize;
        // src matrix can have gaps so we need to calculate the address of the start of the next row the hard way
        // see *brief* text in opencv2/core/mat.hpp for address calculation
        srcptr = 0;
        for (int t=sourceMat.dims-2;t>=0;t--) {
            if (coordinates[t]>=sourceMat.size[t]) {
                if (t==0) break;
            srcptr += sourceMat.step[t]*coordinates[t];

   // this constructor assumes that imagebuffer is gap-less (if not, a complete array of step sizes must be given, too)
   cv::Mat destination=cv::Mat(sourceMat.dims, sourceMat.size, sourceMat.type(), (void*)imagebuffer);

   // and just to proof that sourceImage points to the same memory as origSource, we strike it through

   cv::imshow("original image",origSource);
   cv::imshow("partial image",sourceMat);
   cv::imshow("copied image",destination);
   while (cv::waitKey(60)!='q');

Node.js - SyntaxError: Unexpected token import

Unfortunately, Node.js doesn't support ES6's import yet.

To accomplish what you're trying to do (import the Express module), this code should suffice

var express = require("express");

Also, be sure you have Express installed by running

$ npm install express

See the Node.js Docs for more information about learning Node.js.

ORA-06550: line 1, column 7 (PL/SQL: Statement ignored) Error

If the value stored in PropertyLoader.RET_SECONDARY_V_ARRAY is not "V_ARRAY", then you are using different types; even if they are declared identically (e.g. both are table of number) this will not work.

You're hitting this data type compatibility restriction:

You can assign a collection to a collection variable only if they have the same data type. Having the same element type is not enough.

You're trying to call the procedure with a parameter that is a different type to the one it's expecting, which is what the error message is telling you.

Update MongoDB field using value of another field

Here's what we came up with for copying one field to another for ~150_000 records. It took about 6 minutes, but is still significantly less resource intensive than it would have been to instantiate and iterate over the same number of ruby objects.

js_query = %({
  $or : [
      'settings.mobile_notifications' : { $exists : false },
      'settings.mobile_admin_notifications' : { $exists : false }

js_for_each = %(function(user) {
  if (!user.settings.hasOwnProperty('mobile_notifications')) {
    user.settings.mobile_notifications = user.settings.email_notifications;
  if (!user.settings.hasOwnProperty('mobile_admin_notifications')) {
    user.settings.mobile_admin_notifications = user.settings.email_admin_notifications;

js = "db.users.find(#{js_query}).forEach(#{js_for_each});"
Mongoid::Sessions.default.command('$eval' => js)

How to delete empty folders using windows command prompt?

This is a hybird of the above. It removes ALL files older than X days and removes any empty folders for the given path. To use simply set the days, folderpath and drive

@echo off
set days=30
set folderpath=E:\TEST\
set drive=E:

::Delete files
forfiles -p %folderpath% -s -d -%days% -c "cmd /c del /q @path "

::Delete folders
cd %folderpath%
for /f "usebackq delims=" %%d in (`"dir /ad/b/s | sort /R"`) do rd "%%d"`

Quoting backslashes in Python string literals

What Harley said, except the last point - it's not actually necessary to change the '/'s into '\'s before calling open. Windows is quite happy to accept paths with forward slashes.

infile = open('c:/folder/subfolder/file.txt')

The only time you're likely to need the string normpathed is if you're passing to to another program via the shell (using os.system or the subprocess module).

String Padding in C

One thing that's definitely wrong in the function which forms the original question in this thread, which I haven't seen anyone mention, is that it is concatenating extra characters onto the end of the string literal that has been passed in as a parameter. This will give unpredictable results. In the example call of the function, the string literal "Hello" will be hard-coded into the program, so presumably concatenating onto the end of it will dangerously write over code. If you want to return a string which is bigger than the original then you need to make sure you allocate it dynamically and then delete it in the calling code when you're done.

Retina displays, high-res background images

Here's a solution that also includes High(er)DPI (MDPI) devices > ~160 dots per inch like quite a few non-iOS Devices (f.e.: Google Nexus 7 2012):

.box {
    background: url( 'img/box-bg.png' ) no-repeat top left;
    width: 200px;
    height: 200px;
@media only screen and ( -webkit-min-device-pixel-ratio: 1.3 ),
       only screen and (    min--moz-device-pixel-ratio: 1.3 ),
       only screen and (      -o-min-device-pixel-ratio: 2.6/2 ), /* returns 1.3, see Dev.Opera */
       only screen and (         min-device-pixel-ratio: 1.3 ),
       only screen and ( min-resolution: 124.8dpi ),
       only screen and ( min-resolution: 1.3dppx ) {

       .box {
           background: url( 'img/[email protected]' ) no-repeat top left / 200px 200px;


As @3rror404 included in his edit after receiving feedback from the comments, there's a world beyond Webkit/iPhone. One thing that bugs me with most solutions around so far like the one referenced as source above at CSS-Tricks, is that this isn't taken fully into account.
The original source went already further.

As an example the Nexus 7 (2012) screen is a TVDPI screen with a weird device-pixel-ratio of 1.325. When loading the images with normal resolution they are upscaled via interpolation and therefore blurry. For me applying this rule in the media query to include those devices succeeded in best customer feedback.

SQL query to find Nth highest salary from a salary table

This is salary table

enter image description here

SELECT  amount FROM  salary 
GROUP by amount
ORDER BY  amount DESC 
LIMIT n-1 , 1


FROM  salary 
ORDER BY  amount DESC 
LIMIT n-1 , 1

Re-assign host access permission to MySQL user

I haven't had to do this, so take this with a grain of salt and a big helping of "test, test, test".

What happens if (in a safe controlled test environment) you directly modify the Host column in the mysql.user and probably mysql.db tables? (E.g., with an update statement.) I don't think MySQL uses the user's host as part of the password encoding (the PASSWORD function doesn't suggest it does), but you'll have to try it to be sure. You may need to issue a FLUSH PRIVILEGES command (or stop and restart the server).

For some storage engines (MyISAM, for instance), you may also need to check/modify the .frm file any views that user has created. The .frm file stores the definer, including the definer's host. (I have had to do this, when moving databases between hosts where there had been a misconfiguration causing the wrong host to be recorded...)

Print range of numbers on same line

[print(i, end = ' ') for i in range(10)]
0 1 2 3 4 5 6 7 8 9

This is a list comprehension method of answer same as @Anubhav

sql server Get the FULL month name from a date

         + RIGHT(CONVERT(VARCHAR(12), GETDATE(), 107), 9) AS [Month DD, YYYY]

OR Date without Comma Between date and year, you can use the following

           + ' ' + CAST(YEAR(GETDATE()) AS VARCHAR(4)) AS [Month DD YYYY]

Set the maximum character length of a UITextField in Swift

  1. Your view controller should conform to UITextFieldDelegate, like below:

    class MyViewController: UIViewController, UITextFieldDelegate {
  2. Set the delegate of your textfield: myTextField.delegate = self

  3. Implement the method in your view controller : textField(_:shouldChangeCharactersInRange:replacementString:)

All together:

class MyViewController: UIViewController,UITextFieldDelegate  //set delegate to class 

@IBOutlet var mytextField: UITextField             //  textfield variable 

override func viewDidLoad() {
    mytextField.delegate = self                  //set delegate

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange,
                       replacementString string: String) -> Bool
    let maxLength = 4
    let currentString: NSString = textField.text
    let newString: NSString =
             currentString.stringByReplacingCharactersInRange(range, withString: string)
    return newString.length <= maxLength

For Swift 4

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
    let maxLength = 1
    let currentString: NSString = (textField.text ?? "") as NSString
    let newString: NSString =
        currentString.replacingCharacters(in: range, with: string) as NSString
    return newString.length <= maxLength

Allowing only a specified set of characters to be entered into a given text field

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
  var result = true
  if mytextField == numberField {
    if count(string) > 0 {
      let disallowedCharacterSet = NSCharacterSet(charactersInString: "0123456789.-").invertedSet
      let replacementStringIsLegal = string.rangeOfCharacterFromSet(disallowedCharacterSet) == nil
      result = replacementStringIsLegal
  return result

How to program an iOS text field that takes only numeric input with a maximum length

What causes signal 'SIGILL'?

It means the CPU attempted to execute an instruction it didn't understand. This could be caused by corruption I guess, or maybe it's been compiled for the wrong architecture (in which case I would have thought the O/S would refuse to run the executable). Not entirely sure what the root issue is.

How can I use SUM() OVER()

Seems like you expected the query to return running totals, but it must have given you the same values for both partitions of AccountID.

To obtain running totals with SUM() OVER (), you need to add an ORDER BY sub-clause after PARTITION BY …, like this:


But remember, not all database systems support ORDER BY in the OVER clause of a window aggregate function. (For instance, SQL Server didn't support it until the latest version, SQL Server 2012.)

Pass a String from one Activity to another Activity in Android

Most likely as others have said you want to attach it to your Intent with putExtra. But I want to throw out there that depending on what your use case is, it may be better to have one activity that switches between two fragments. The data is stored in the activity and never has to be passed.

fatal error LNK1104: cannot open file 'libboost_system-vc110-mt-gd-1_51.lib'

I had the same problem and my mistake was that I had installed the binary boost_1_55_0-msvc-11.0-32.exe to use with visual c++ 2010 which has the version v100 (project properties->ConfiguratioProperties->General->platformTooset) not v110 as visual c++ 2012. So I dowloaded boost_1_55_0-msvc-10.0-32.exe and now everything is ok so far.

Full-screen responsive background image

This worked for me, so posting this.

.my-container {
  position: relative;
  background: #696969;
  overflow: hidden;
.my-container:before {
  content: ' ';
  display: block;
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
  opacity: 0.6;
  background-image: url('');
  background-repeat: no-repeat;
  background-position: 50% 0;
  -ms-background-size: cover;
  -o-background-size: cover;
  -moz-background-size: cover;
  -webkit-background-size: cover;
  background-size: cover;

Rotate label text in seaborn factorplot

You can also use plt.setp as follows:

import matplotlib.pyplot as plt
import seaborn as sns

plot=sns.barplot(data=df,  x=" ", y=" ")
plt.setp(plot.get_xticklabels(), rotation=90)

to rotate the labels 90 degrees.

Best way to parse command-line parameters?

I like sliding over arguments for relatively simple configurations.

var name = ""
var port = 0
var ip = ""
args.sliding(2, 2).toList.collect {
  case Array("--ip", argIP: String) => ip = argIP
  case Array("--port", argPort: String) => port = argPort.toInt
  case Array("--name", argName: String) => name = argName

How can I display a messagebox in ASP.NET?

you can use clientscript. MSDN : Clientscript

String scriptText = 
        "ConfirmSubmit", scriptText);

try this

ClientScript.RegisterStartupScript(this.GetType(), "JSScript", scriptText); 

ClientScript.RegisterClientScriptBlock(this.GetType(), "alert", scriptText); //use this 

How to change navbar/container width? Bootstrap 3

Proper way to do it is to change the width on the online customizer here:

download the recompiled source, overwrite the existing bootstrap dist dir, and reload (mind the browser cache!!!)

All your changes will be retained in the .json configuration file

To apply again the all the changes just upload the json file and you are ready to go

How to format LocalDate to string?

There is a built-in way to format LocalDate in Joda library

import org.joda.time.LocalDate;

LocalDate localDate =;
String dateFormat = "MM/dd/yyyy";

In case you don't have it already - add this to the build.gradle:

implementation 'joda-time:joda-time:2.9.5'

Happy coding! :)

React Native Error: ENOSPC: System limit for number of file watchers reached

You can fix it, that increasing the amount of inotify watchers.

If you are not interested in the technical details and only want to get Listen to work:

  • If you are running Debian, RedHat, or another similar Linux distribution, run the following in a terminal:

    $ echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p

  • If you are running ArchLinux, run the following command instead

    $ echo fs.inotify.max_user_watches=524288 | sudo tee /etc/sysctl.d/40-max-user-watches.conf && sudo sysctl --system

Then paste it in your terminal and press on enter to run it.

The Technical Details

Listen uses inotify by default on Linux to monitor directories for changes. It's not uncommon to encounter a system limit on the number of files you can monitor. For example, Ubuntu Lucid's (64bit) inotify limit is set to 8192.

You can get your current inotify file watch limit by executing:

$ cat /proc/sys/fs/inotify/max_user_watches

When this limit is not enough to monitor all files inside a directory, the limit must be increased for Listen to work properly.

You can set a new limit temporary with:

$ sudo sysctl fs.inotify.max_user_watches=524288
$ sudo sysctl -p

If you like to make your limit permanent, use:

$ echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf
$ sudo sysctl -p

You may also need to pay attention to the values of max_queued_events and max_user_instances if listen keeps on complaining.

Excel VBA, error 438 "object doesn't support this property or method

The Error is here

lastrow = wsPOR.Range("A" & Rows.Count).End(xlUp).Row + 1

wsPOR is a workbook and not a worksheet. If you are working with "Sheet1" of that workbook then try this

lastrow = wsPOR.Sheets("Sheet1").Range("A" & _
          wsPOR.Sheets("Sheet1").Rows.Count).End(xlUp).Row + 1


wsPOR.Range("A2:G" & lastrow).Select

should be

wsPOR.Sheets("Sheet1").Range("A2:G" & lastrow).Select

How to tell a Mockito mock object to return something different the next time it is called?

For Anyone using spy() and the doReturn() instead of the when() method:

what you need to return different object on different calls is this:



For classic mocks:

when(this.mockFoo.someMethod()).thenReturn(obj1, obj2);

or with an exception being thrown:

        .thenThrow(new IllegalArgumentException())
        .thenReturn(obj2, obj3);

Return multiple values from a function in swift

Return a tuple:

func getTime() -> (Int, Int, Int) {
    return ( hour, minute, second)

Then it's invoked as:

let (hour, minute, second) = getTime()


let time = getTime()
println("hour: \(time.0)")

Can Rails Routing Helpers (i.e. mymodel_path(model)) be Used in Models?

I've found the answer regarding how to do this myself. Inside the model code, just put:

For Rails <= 2:

include ActionController::UrlWriter

For Rails 3:

include Rails.application.routes.url_helpers

This magically makes thing_path(self) return the URL for the current thing, or other_model_path(self.association_to_other_model) return some other URL.

warning: incompatible implicit declaration of built-in function ‘xyz’

In C, using a previously undeclared function constitutes an implicit declaration of the function. In an implicit declaration, the return type is int if I recall correctly. Now, GCC has built-in definitions for some standard functions. If an implicit declaration does not match the built-in definition, you get this warning.

To fix the problem, you have to declare the functions before using them; normally you do this by including the appropriate header. I recommend not to use the -fno-builtin-* flags if possible.

Instead of stdlib.h, you should try:

#include <string.h>

That's where strcpy and strncpy are defined, at least according to the strcpy(2) man page.

The exit function is defined in stdlib.h, though, so I don't know what's going on there.

Infinity symbol with HTML

You can use the following:

  • literal: 8 (if the encoding you use can encode it — UTF-8 can, for example)
  • character reference: &#8734; (decimal), &#x221E; (hexadecimal)
  • entity reference: &infin;

But whether it is displayed correctly does also depend on the font the text is displayed with.

How to serialize an object to XML without getting xmlns="..."?

If you want to get rid of the extra xmlns:xsi="" and xmlns:xsd="", but still keep your own namespace xmlns="", you use the same code as above except for this simple change:

//  Add lib namespace with empty prefix  
ns.Add("", "");   

MVC 4 - Return error message from Controller - Show in View

You can add this to your _Layout.cshtml:

@using MyProj.ViewModels;
    @if (TempData["UserMessage"] != null)
        var message = (MessageViewModel)TempData["UserMessage"];
        <div class="alert @message.CssClassName" role="alert">
            <button type="button" class="close" data-dismiss="alert" aria-label="Close">
                <span aria-hidden="true">&times;</span>

Then if you want to throw an error message in your controller:

    TempData["UserMessage"] = new MessageViewModel() { CssClassName = "alert-danger  alert-dismissible", Title = "Error", Message = "This is an error message" };


public class MessageViewModel
        public string CssClassName { get; set; }
        public string Title { get; set; }
        public string Message { get; set; }

Note: Using Bootstrap 4 classes.

How can I delete a user in linux when the system says its currently used in a process

First use pkill or kill -9 <pid> to kill the process.

Then use following userdel command to delete user,

userdel -f cafe_fixer

According to userdel man page:

-f, --force

This option forces the removal of the user account, even if the user is still logged in. It also forces userdel to remove the user's home directory and mail spool, even if another user uses the same home directory or if the mail spool is not owned by the specified user. If USERGROUPS_ENAB is defined to yes in /etc/login.defs and if a group exists with the same name as the deleted user, then this group will be removed, even if it is still the primary group of another user.

Edit 1: (by @Ajedi32)

Note: This option (i.e. --force) is dangerous and may leave your system in an inconsistent state.

Edit 2: (by @socketpair)

In spite of the description about some files, this key allows removing the user while it is in use. Don't forget to chdir / before, because this command will also remove home directory.

Resizing UITableView to fit content

In case you don't want to track table view's content size changes yourself, you might find this subclass useful.

protocol ContentFittingTableViewDelegate: UITableViewDelegate {
    func tableViewDidUpdateContentSize(_ tableView: UITableView)

class ContentFittingTableView: UITableView {

    override var contentSize: CGSize {
        didSet {
            if !constraints.isEmpty {
            } else {

            if contentSize != oldValue {
                if let delegate = delegate as? ContentFittingTableViewDelegate {

    override var intrinsicContentSize: CGSize {
        return contentSize

    override func sizeThatFits(_ size: CGSize) -> CGSize {
        return contentSize

WampServer orange icon

Please read through the wamp installation carefully, It lists the steps for wamp not turning green clearly. Please read through steps while installing wamp server. It solves most of the bootstrap issues.

Your port 80 is actually used by : Server: Microsoft-HTTPAPI/2.0

Modify ports: It works Appache port from 8080 to 7080 Maria DB port from 3306 to 3307 Mysql DB port from 3308 to 3309

To verify that all VC ++ packages are installed and with the latest versions, you can use the tool: Also know the difference between VC++ and VS code

Visual Studio is a suite of component-based software development tools and other technologies for building powerful, high-performance applications. On the other hand, Visual Studio Code is detailed as "Build and debug modern web and cloud applications, by Microsoft".

enter image description here

How to enable cURL in PHP / XAMPP

PHP 7^ version:

sudo apt-get install php-curl
sudo service apache2 restart

sqlite3.ProgrammingError: Incorrect number of bindings supplied. The current statement uses 1, and there are 74 supplied

You need to pass in a sequence, but you forgot the comma to make your parameters a tuple:

cursor.execute('INSERT INTO images VALUES(?)', (img,))

Without the comma, (img) is just a grouped expression, not a tuple, and thus the img string is treated as the input sequence. If that string is 74 characters long, then Python sees that as 74 separate bind values, each one character long.

>>> len(img)
>>> len((img,))

If you find it easier to read, you can also use a list literal:

cursor.execute('INSERT INTO images VALUES(?)', [img])

Maximum on http header values?

If you are going to use any DDOS provider like Akamai, they have a maximum limitation of 8k in the response header size. So essentially try to limit your response header size below 8k.

Unstaged changes left after git reset --hard

In a similar situation. As a result of many years of torment with many programmers who were able to stuff different encodings of the ends of lines (.asp, .js, .css ... not the essence) into one file. Some time ago refused .gitattributes. Settings for repo left autorclf = true andsafecrlf = warn.

The last problem arose when synchronizing from the archive with different ends of lines. After copying from the archive, in the git status many files are changed with the note

The line will have its original line endings in your working directory. warning: LF will be replaced by CRLF in ...

Tips from How to normalize working tree line endings in Git? helped

git add -u

Android difference between Two Dates

Try this out.

int day = 0;
        int hh = 0;
        int mm = 0;
        try {
            SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MMM-yyyy 'at' hh:mm aa");
            Date oldDate = dateFormat.parse(oldTime);
            Date cDate = new Date();
            Long timeDiff = cDate.getTime() - oldDate.getTime();
            day = (int) TimeUnit.MILLISECONDS.toDays(timeDiff);
            hh = (int) (TimeUnit.MILLISECONDS.toHours(timeDiff) - TimeUnit.DAYS.toHours(day));
            mm = (int) (TimeUnit.MILLISECONDS.toMinutes(timeDiff) - TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS.toHours(timeDiff)));

        } catch (ParseException e) {

        if (mm <= 60 && hh!= 0) {
            if (hh <= 60 && day != 0) {
                return day + " DAYS AGO";
            } else {
                return hh + " HOUR AGO";
        } else {
            return mm + " MIN AGO";

How to get the containing form of an input?

Every input has a form property which points to the form the input belongs to, so simply:

function doSomething(element) {
  var form = element.form;

Dynamically replace img src attribute with jQuery

In my case, I replaced the src taq using:

   $('#gmap_canvas').attr('src', newSrc);

Android: Proper Way to use onBackPressed() with Toast

If you want to exit your application from direct Second Activity without going to First Activity then try this code..`

In Second Activity put this code..

public void onBackPressed() {
    new AlertDialog.Builder(this)
            .setTitle("Really Exit?")
            .setMessage("Are you sure you want to exit?")
            .setNegativeButton(, null)
            .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface arg0, int arg1) {
                    setResult(RESULT_OK, new Intent().putExtra("EXIT", true));


And Your First Activity Put this code.....

public class FirstActivity extends AppCompatActivity {

Button next;
private final static int EXIT_CODE = 100;

protected void onCreate(Bundle savedInstanceState) {
    next = (Button) findViewById(;
    next.setOnClickListener(new View.OnClickListener() {

        public void onClick(View view) {

            startActivityForResult(new Intent(FirstActivity.this, SecondActivity.class), EXIT_CODE);

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == EXIT_CODE) {
        if (resultCode == RESULT_OK) {
            if (data.getBooleanExtra("EXIT", true)) {


Table columns, setting both min and max width with css

Tables work differently; sometimes counter-intuitively.

The solution is to use width on the table cells instead of max-width.

Although it may sound like in that case the cells won't shrink below the given width, they will actually.
with no restrictions on c, if you give the table a width of 70px, the widths of a, b and c will come out as 16, 42 and 12 pixels, respectively.
With a table width of 400 pixels, they behave like you say you expect in your grid above.
Only when you try to give the table too small a size (smaller than a.min+b.min+the content of C) will it fail: then the table itself will be wider than specified.

I made a snippet based on your fiddle, in which I removed all the borders and paddings and border-spacing, so you can measure the widths more accurately.

table {_x000D_
  width: 70px;_x000D_
table, tbody, tr, td {_x000D_
  margin: 0;_x000D_
  padding: 0;_x000D_
  border: 0;_x000D_
  border-spacing: 0;_x000D_
.a, .c {_x000D_
  background-color: red;_x000D_
.b {_x000D_
  background-color: #F77;_x000D_
.a {_x000D_
  min-width: 10px;_x000D_
  width: 20px;_x000D_
  max-width: 20px;_x000D_
.b {_x000D_
  min-width: 40px;_x000D_
  width: 45px;_x000D_
  max-width: 45px;_x000D_
.c {}
    <td class="a">A</td>_x000D_
    <td class="b">B</td>_x000D_
    <td class="c">C</td>_x000D_

Filtering by Multiple Specific Model Properties in AngularJS (in OR relationship)

Filter can be a JavaScript object with fields and you can have expression as:

ng-repeat= 'item in list | filter :{property:value}'

Check if argparse optional argument is set or not

Here is my solution to see if I am using an argparse variable

import argparse

ap = argparse.ArgumentParser()
ap.add_argument("-1", "--first", required=True)
ap.add_argument("-2", "--second", required=True)
ap.add_argument("-3", "--third", required=False) 
# Combine all arguments into a list called args
args = vars(ap.parse_args())
if args["third"] is not None:
# do something

This might give more insight to the above answer which I used and adapted to work for my program.

CSV in Python adding an extra carriage return, on Windows

You have to add attribute newline="\n" to open function like this:

with open('file.csv','w',newline="\n") as out:
    csv_out = csv.writer(out, delimiter =';')

ldconfig error: is not a symbolic link

I simply ran the command below:

export LD_LIBRARY_PATH=/usr/lib/

Now it is working fine.

What is the difference between XML and XSD?

Basically an XSD file defines how the XML file is going to look like. It's a Schema file which defines the structure of the XML file. So it specifies what the possible fields are and what size they are going to be.

An XML file is an instance of XSD as it uses the rules defined in the XSD.

Getting a union of two arrays in JavaScript

Simple way to deal with merging single array values.

var values[0] = {"id":1235,"name":"value 1"}
values[1] = {"id":4323,"name":"value 2"}

var object=null;
var first=values[0];
for (var i in values) 
 object= $.merge(values[i],first)

How do I send email with JavaScript without opening the mail client?

Directly From Client

Send an email using only JavaScript

in short: 
1. register for Mandrill to get an API key
2. load jQuery
3. use $.ajax to send an email

Like this -

function sendMail() {
      type: 'POST',
      url: '',
      data: {
        'key': 'YOUR API KEY HERE',
        'message': {
          'from_email': '[email protected]',
          'to': [
                'email': '[email protected]',
                'name': 'RECIPIENT NAME (OPTIONAL)',
                'type': 'to'
          'autotext': 'true',
          'subject': 'YOUR SUBJECT HERE!',
     }).done(function(response) {
       console.log(response); // if you're into that sorta thing

Note: Keep in mind that your API key is visible to anyone, so any malicious user may use your key to send out emails that can eat up your quota.

Indirect via Your Server - secure

To overcome the above vulnerability, you can modify your own server to send the email after session based authentication.

node.js -

var mandrill = require('node-mandrill')('<your API Key>'); 

function sendEmail ( _name, _email, _subject, _message) {
    mandrill('/messages/send', {
        message: {
            to: [{email: _email , name: _name}],
            from_email: '[email protected]',
            subject: _subject,
            text: _message
    }, function(error, response){
        if (error) console.log( error );
        else console.log(response);

// define your own email api which points to your server. '/api/sendemail/', function(req, res){

    var _name =;
    var _email =;
    var _subject = req.body.subject;
    var _messsage = req.body.message;

    //implement your spam protection or checks. 

    sendEmail ( _name, _email, _subject, _message );


and then use use $.ajax on client to call your email API.

Opening database file from within SQLite command-line shell

I think the simplest way to just open a single database and start querying is:

sqlite> .open "test.db"
sqlite> SELECT * FROM table_name ... ;

Notice: This works only for versions 3.8.2+

How to add a "confirm delete" option in ASP.Net Gridview?

I was having problems getting a commandField Delete button to honor the 'return false' response to when a user clicked cancel on the 'Are you sure' pop-up that one gets with using the javascript confirm() function. I didn't want to change it to a template field.

The problem, as I see it, was that these commandField Buttons already have some Javascript associated with them to perform the postback. No amount of simply appending the confirm() function was effective.

Here's how I solved it:

Using JQuery, I first found each delete button on the page (there are several), then manipulated the button's associated Javascript based on whether the visitor agreed or canceled the confirming pop-up.

<script language="javascript" type="text/javascript">
$(document).ready(function() {

               $('input[type="button"]').each(function() {

                   if ($(this).val() == "Delete") {
                       var curEvent = $(this).attr('onclick');
                       var newContent = "if(affirmDelete() == true){" + curEvent + "};" 

function affirmDelete() {    
               return confirm('Are you sure?');

Git - Ignore files during merge

I got over this issue by using git merge command with the --no-commit option and then explicitly removed the staged file and ignore the changes to the file. E.g.: say I want to ignore any changes to myfile.txt I proceed as follows:

git merge --no-ff --no-commit <merge-branch>
git reset HEAD myfile.txt
git checkout -- myfile.txt
git commit -m "merged <merge-branch>"

You can put statements 2 & 3 in a for loop, if you have a list of files to skip.

JAX-WS client : what's the correct path to access the local WSDL?

The best option is to use jax-ws-catalog.xml

When you compile the local WSDL file , override the WSDL location and set it to something like


Don't worry this is only a URI and not a URL , meaning you don't have to have the WSDL available at that address.
You can do this by passing the wsdllocation option to the wsdl to java compiler.

Doing so will change your proxy code from

static {
    URL url = null;
    try {
        URL baseUrl;
        baseUrl =".");
        url = new URL(baseUrl, "file:/C:/local/path/to/wsdl/SOAService.wsdl");
    } catch (MalformedURLException e) {
        logger.warning("Failed to create URL for the wsdl Location: 'file:/C:/local/path/to/wsdl/SOAService.wsdl', retrying as a local file");


static {
    URL url = null;
    try {
        URL baseUrl;
        baseUrl =".");
        url = new URL(baseUrl, "http://localhost/wsdl/SOAService.wsdl");
    } catch (MalformedURLException e) {
        logger.warning("Failed to create URL for the wsdl Location: 'http://localhost/wsdl/SOAService.wsdl', retrying as a local file");

Notice file:// changed to http:// in the URL constructor.

Now comes in jax-ws-catalog.xml. Without jax-ws-catalog.xml jax-ws will indeed try to load the WSDL from the location

and fail, as no such WSDL will be available.

But with jax-ws-catalog.xml you can redirect jax-ws to a locally packaged WSDL whenever it tries to access the WSDL @


Here's jax-ws-catalog.xml

<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog" prefer="system">
        <system systemId="http://localhost/wsdl/SOAService.wsdl"

What you are doing is telling jax-ws that when ever it needs to load WSDL from

, it should load it from local path wsdl/SOAService.wsdl.

Now where should you put wsdl/SOAService.wsdl and jax-ws-catalog.xml ? That's the million dollar question isn't it ?
It should be in the META-INF directory of your application jar.

so something like this

|__ META-INF    
    |__ jax-ws-catalog.xml  
    |__ wsdl  
        |__ SOAService.wsdl  

This way you don't even have to override the URL in your client that access the proxy. The WSDL is picked up from within your JAR, and you avoid having to have hard-coded filesystem paths in your code.

More info on jax-ws-catalog.xml

Hope that helps

How to put img inline with text

Please make use of the code below to display images inline:

<img style='vertical-align:middle;' src='somefolder/icon.gif'>
<div style='vertical-align:middle; display:inline;'>
Your text here

SQL, How to Concatenate results?

Small update on Marc we will have additional " , " at the end. i used stuff function to remove extra semicolon .

       SELECT STUFF((  SELECT ',' + ModuleValue AS ModuleValue
                           FROM ModuleValue WHERE ModuleID=@ModuleID
                      FOR XML PATH('') 
                     ), 1, 1, '' )

GitHub relative link in Markdown file

This question is pretty old, but it still seems important, as it isn't easy to put relative references from to wiki pages on Github.

I played around a little bit and this relative link seems to work pretty well:

[Your wiki page](../../wiki/your-wiki-page)

The two ../ will remove /blob/master/ and use your base as a starting point. I haven't tried this on other repositories than Github, though (there may be compatibility issues).

'const string' vs. 'static readonly string' in C#

Here is a good breakdown of the pros and cons:

So, it appears that constants should be used when it is very unlikely that the value will ever change, or if no external apps/libs will be using the constant. Static readonly fields should be used when run-time calculation is required, or if external consumers are a factor.

jQuery date/time picker

By far the nicest and simplest DateTime picker option is

It is an extension of the jQuery UI Datepicker so it will support the same themes as well it works very much the same way, similar syntax, etc. This should be packaged with the jQuery UI imo.

Can't access Tomcat using IP address

Windows Firewall cause issue after uninstalling Oracle JDK and installing OpenJDK on Windows Server 2008 R2.

Tomcat 7 and Tomcat 8 not access on other machine after this.

Follow below path to add new rule

 --> Windows Firewall with Advanced Security on Local Computer
 --> Inbound Rule 
 -->Add New Rule 
      with specific port you have required for Tomcat application.

How much does it cost to develop an iPhone application?

The Barack Obama app took 22 days to develop from first code to release. Three developers (although not all of them were full time). 10 people total. Figure 500-1000 man hours. Contracting rates are $100-150/hr. Figure $50000-$150000. Compare your app to and scale accordingly.

Attaching a Sass/SCSS to HTML docs

You can not "attach" a SASS/SCSS file to an HTML document.

SASS/SCSS is a CSS preprocessor that runs on the server and compiles to CSS code that your browser understands.

There are client-side alternatives to SASS that can be compiled in the browser using javascript such as LESS CSS, though I advise you compile to CSS for production use.

It's as simple as adding 2 lines of code to your HTML file.

<link rel="stylesheet/less" type="text/css" href="styles.less" />
<script src="less.js" type="text/javascript"></script>

How to completely uninstall Visual Studio 2010?

Download and install IOBIT uninstaller:, find the date in which you install Visual Studio and select all programas from that date r elated to VS. Then run de batch uninstaller. It is not a fully automated solution but it is a lot quicker than going one by one int he add / remove programs in Windows. It even has a power scan to clean the registry.

Replace deprecated preg_replace /e with preg_replace_callback

You can use an anonymous function to pass the matches to your function:

$result = preg_replace_callback(
    function($m) { return CallFunction($m[1], $m[2], $m[3], $m[4], $m[5]); },

Apart from being faster, this will also properly handle double quotes in your string. Your current code using /e would convert a double quote " into \".

CSS Input Type Selectors - Possible to have an "or" or "not" syntax?

CSS3 has a pseudo-class called :not()

input:not([type='checkbox']) {    
    visibility: hidden;
<p>If <code>:not()</code> is supported, you'll only see the checkbox.</p>
  <li>text: (<input type="text">)</li>  
  <li>password (<input type="password">)</li>       
  <li>checkbox (<input type="checkbox">)</li> 

Multiple selectors

As Vincent mentioned, it's possible to string multiple :not()s together:


CSS4, which is supported in many of the latest browser releases, allows multiple selectors in a :not()


Legacy support

All modern browsers support the CSS3 syntax. At the time this question was asked, we needed a fall-back for IE7 and IE8. One option was to use a polyfill like IE9.js. Another was to exploit the cascade in CSS:

input {
   // styles for most inputs

input[type=checkbox] {
  // revert back to the original style

input.checkbox {
  // for completeness, this would have worked even in IE3!

Can I force a UITableView to hide the separator between empty cells?

Setting the table's separatorStyle to UITableViewCellSeparatorStyleNone (in code or in IB) should do the trick.

Capturing standard out and error with Start-Process

That's how Start-Process was designed for some reason. Here's a way to get it without sending to file:

$pinfo = New-Object System.Diagnostics.ProcessStartInfo
$pinfo.FileName = "ping.exe"
$pinfo.RedirectStandardError = $true
$pinfo.RedirectStandardOutput = $true
$pinfo.UseShellExecute = $false
$pinfo.Arguments = "localhost"
$p = New-Object System.Diagnostics.Process
$p.StartInfo = $pinfo
$p.Start() | Out-Null
$stdout = $p.StandardOutput.ReadToEnd()
$stderr = $p.StandardError.ReadToEnd()
Write-Host "stdout: $stdout"
Write-Host "stderr: $stderr"
Write-Host "exit code: " + $p.ExitCode

How to check if any Checkbox is checked in Angular

If you don't want to use a watcher, you can do something like this:

<input type='checkbox' ng-init='checkStatus=false' ng-model='checkStatus' ng-click='doIfChecked(checkStatus)'>

How do you use window.postMessage across domains?

You should post a message from frame to parent, after loaded.

frame script:

$(document).ready(function() {
    window.parent.postMessage("I'm loaded", "*");

And listen it in parent:

function listenMessage(msg) {

if (window.addEventListener) {
    window.addEventListener("message", listenMessage, false);
} else {
    window.attachEvent("onmessage", listenMessage);

Use this link for more info:

How to find the size of an int[]?

Assuming you merely want to know the size of an array whose type you know (int) but whose size, obviously, you don't know, it is suitable to verify whether the array is empty, otherwise you will end up with a division by zero (causing a Float point exception).

int array_size(int array[]) {
    if(sizeof(array) == 0) {
        return 0;
    return sizeof(array)/sizeof(array[0]);

Opening a remote machine's Windows C drive

If it's not the Home edition of XP, you can use \\servername\c$

Mark Brackett's comment:

Note that you need to be an Administrator on the local machine, as the share permissions are locked down

How can I get href links from HTML using Python?

Using BS4 for this specific task seems overkill.

Try instead:

website = urllib2.urlopen('')
html =
files = re.findall('href="(.*tgz|.*tar.gz)"', html)
print sorted(x for x in (files))

I found this nifty piece of code on and works for me quite well.

I tested it only on my scenario of extracting a list of files from a web folder that exposes the files\folder in it, e.g.:

enter image description here

and I got a sorted list of the files\folders under the URL

Detect whether Office is 32bit or 64bit via the registry

I've found a much easier way. Using Powershell, we can hook Excel as a COM object.

$user = $env:UserName
$msoExcel = New-Object -ComObject Excel.Application  
$msoExcel | Select-Object -Property OperatingSystem | Out-File "\\SERVER\Path\To\Dump\msoVersion-$user.txt"

When requesting the OperatingSystem this way, we get strange results, have a look here. PC3 is mine.

I hope this works for you guys. Sorry for the lack of code; my scripts are mostly functional.

Edit: Don't forget to add the code to close Excel after you're done retrieving the data.
After testing this code yesterday I had tons of Excel opening and crashing all of a sudden..
This will make sure you'll keep users and admins happy (:

Remove-Variable msoExcel

How to add a “readonly” attribute to an <input>?

Use the setAttribute property. Note in example that if select 1 apply the readonly attribute on textbox, otherwise remove the attribute readonly.

document.getElementById("box1").onchange = function(){
  if(document.getElementById("box1").value == 1) {
    document.getElementById("codigo").setAttribute("readonly", true);
  } else {

<input type="text" name="codigo" id="codigo"/>

<select id="box1">
<option value="0" >0</option>
<option value="1" >1</option>
<option value="2" >2</option>

How do I prevent a parent's onclick event from firing when a child anchor is clicked?

If a child element is clicked, then the event bubbles up to the parent and !== event.currentTarget.

So in your function, you can check this and return early, i.e.:

var url = $("#clickable a").attr("href");
$("#clickable").click(function(event) {
    if ( !== event.currentTarget ){
        // user clicked on a child and we ignore that
    window.location = url;
    return true;

Excel: last character/string match in a string

Considering a part of a Comment made by @SSilk my end goal has really been to get everything to the right of that last occurence an alternative approach with a very simple formula is to copy a column (say A) of strings and on the copy (say ColumnB) apply Find and Replace. For instance taking the example: Drive:\Folder\SubFolder\Filename.ext

Find what

This returns what remains (here Filename.ext) after the last instance of whatever character is chosen (here \) which is sometimes the objective anyway and facilitates finding the position of the last such character with a short formula such as:


Can you split/explode a field in a MySQL query?

Until now, I wanted to keep those comma separated lists in my SQL db - well aware of all warnings!

I kept thinking that they have benefits over lookup tables (which provide a way to a normalized data base). After some days of refusing, I've seen the light:

  • Using lookup tables is NOT causing more code than those ugly string operations when using comma separated values in one field.
  • The lookup table allows for native number formats and is thus NOT bigger than those csv fields. It is SMALLER though.
  • The involved string operations are slim in high level language code (SQL and PHP), but expensive compared to using arrays of integers.
  • Databases are not meant to be human readable, and it is mostly stupid to try to stick to structures due to their readability / direct editability, as I did.

In short, there is a reason why there is no native SPLIT() function in MySQL.

What is the use of the square brackets [] in sql statements?

The brackets are required if you use keywords or special chars in the column names or identifiers. You could name a column [First Name] (with a space)--but then you'd need to use brackets every time you referred to that column.

The newer tools add them everywhere just in case or for consistency.

How do I fetch lines before/after the grep result in bash?

You can use the -B and -A to print lines before and after the match.

grep -i -B 10 'error' data

Will print the 10 lines before the match, including the matching line itself.

SHA-1 fingerprint of keystore certificate

First there is same .jar file that in fb-sdk android-support-v4.jar.
Then generate SHA1 key using:

PackageInfo info;
try {

    info = getPackageManager().getPackageInfo(
        "com.example.worldmission", PackageManager.GET_SIGNATURES);

    for (Signature signature : info.signatures) {
        MessageDigest md;
        md = MessageDigest.getInstance("SHA");
        String something = new String(Base64.encode(md.digest(), 0));
        Log.e("Hash key", something);
        System.out.println("Hash key" + something);

} catch (NameNotFoundException e1) {
    Log.e("name not found", e1.toString());
} catch (NoSuchAlgorithmException e) {
    Log.e("no such an algorithm", e.toString());
} catch (Exception e) {
    Log.e("exception", e.toString());

What is the meaning of "int(a[::-1])" in Python?

Assuming a is a string. The Slice notation in python has the syntax -


So, when you do a[::-1], it starts from the end towards the first taking each element. So it reverses a. This is applicable for lists/tuples as well.

Example -

>>> a = '1234'
>>> a[::-1]

Then you convert it to int and then back to string (Though not sure why you do that) , that just gives you back the string.

How to check if a service is running on Android?

In kotlin you can add boolean variable in companion object and check its value from any class you want:

companion object{
     var isRuning = false


Change it value when service is created and destroyed

 override fun onCreate() {
        isRuning = true

override fun onDestroy() {
    isRuning = false

Get startup type of Windows service using PowerShell

If you update to PowerShell 5 you can query all of the services on the machine and display Name and StartType and sort it by StartType for easy viewing:

Get-Service |Select-Object -Property Name,StartType |Sort-Object -Property StartType

Split array into chunks

Here's a solution using ImmutableJS, where items is an Immutable List and size is the required grouping size.

const partition = ((items, size) => {
  return items.groupBy((items, i) => Math.floor(i/size))

How do I make a simple crawler in PHP?

In it's simplest form:

function crawl_page($url, $depth = 5) {
    if($depth > 0) {
        $html = file_get_contents($url);

        preg_match_all('~<a.*?href="(.*?)".*?>~', $html, $matches);

        foreach($matches[1] as $newurl) {
            crawl_page($newurl, $depth - 1);

        file_put_contents('results.txt', $newurl."\n\n".$html."\n\n", FILE_APPEND);

crawl_page('', 5);

That function will get contents from a page, then crawl all found links and save the contents to 'results.txt'. The functions accepts an second parameter, depth, which defines how long the links should be followed. Pass 1 there if you want to parse only links from the given page.

Escape double quotes in a string

You can use backslash either way;

string str = "He said to me, \"Hello World\". How are you?";

It prints;

He said to me, "Hello World". How are you?

which is exactly same prints with;

string str = @"He said to me, ""Hello World"". How are you?";

Here is a DEMO.

" is still part of your string.

Check out Escape Sequences and String literals from MSDN.

JSON encode MySQL results


$rows = array();

while($r = mysqli_fetch_array($result,MYSQL_ASSOC)) {

 $row_array['result'] = $r;

  array_push($rows,$row_array); // here we push every iteration to an array otherwise you will get only last iteration value

echo json_encode($rows);

Floating point comparison functions for C#

Although the second option is more general, the first option is better when you have an absolute tolerance, and when you have to execute many of these comparisons. If this comparison is say for every pixel in an image, the multiplication in the second options might slow your execution to unacceptable levels of performance.

Authenticate with GitHub using a token

This worked for me using ssh:

SettingsDeveloper settingsGenerate new token.

git remote set-url origin https://[APPLICATION]:[NEW TOKEN][ORGANISATION]/[REPO].git

Validate select box

I don't know how was the plugin the time the question was asked (2009), but I faced the same problem today and solved it this way:

  1. Give your select tag a name attribute. For example in this case

    <select name="myselect">

  2. Instead of working with the attribute value="default" in the tag option, disable the default option as suggested by Jeremy Visser or set value=""

    <option disabled="disabled">Choose...</option>


    <option value="">Choose...</option>

  3. Set the plugin validation rule

    $( "#YOUR_FORM_ID" ).validate({ rules: { myselect: { required: true } } });


    <select name="myselect" class="required">

Obs: redsquare's solution works only if you have just one select in your form. If you want his solution to work with more than one select add a name attribute to your select.

Hope it helps! :)

Have a reloadData for a UITableView animate when changing

Swift 4 version for @dmarnel answer:

tableView.reloadSections(IndexSet(integer: 0), with: .automatic)

DISTINCT clause with WHERE

If you mean all columns whose email is unique:

SELECT * FROM table WHERE email in
     (SELECT email FROM table GROUP BY email HAVING COUNT(email)=1);

Laravel - Eloquent or Fluent random row

In Laravel 7.x and above, you can just do:

$data = Images::all()->random(4);

Delete all duplicate rows Excel vba

There's a RemoveDuplicates method that you could use:

Sub DeleteRows()

    With ActiveSheet
        Set Rng = Range("A1", Range("B1").End(xlDown))
        Rng.RemoveDuplicates Columns:=Array(1, 2), Header:=xlYes
    End With

End Sub

load scripts asynchronously

for HTML5, you can use the 'prefetch'

<link rel="prefetch" href="/style.css" as="style" />

have a look at 'preload' for js.

<link rel="preload" href="used-later.js" as="script">

UIWebView open links in Safari

The other answers have one problem: they rely on the action you do and not on the link itself to decide whether to load it in Safari or in webview.

Now sometimes this is exactly what you want, which is fine; but some other times, especially if you have anchor links in your page, you want really to open only external links in Safari, and not internal ones. In that case you should check the property of your request.

I use that piece of code to check whether I have a hostname in the URL that is being parsed, or if it is embedded html:

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {
    static NSString *regexp = @"^(([a-zA-Z]|[a-zA-Z][a-zA-Z0-9-]*[a-zA-Z0-9])[.])+([A-Za-z]|[A-Za-z][A-Za-z0-9-]*[A-Za-z0-9])$";
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regexp];

    if ([predicate]) {
        [[UIApplication sharedApplication] openURL:request.URL];
        return NO; 
    } else {
        return YES; 

You can of course adapt the regular expression to fit your needs.

How to make a GridLayout fit screen size

Do you know View.getViewTreeObserver().addOnGlobalLayoutListener()

By this you can calculate the sizes.

I achieve your UI effect by GridView:

GridView g;

How to download fetch response in react as file

This worked for me.

const requestOptions = {
method: 'GET',
headers: { 'Content-Type': 'application/json' }

fetch(`${url}`, requestOptions)
.then((res) => {
    return res.blob();
.then((blob) => {
    const href = window.URL.createObjectURL(blob);
    const link = document.createElement('a');
    link.href = href;
    link.setAttribute('download', 'config.json'); //or any other extension
.catch((err) => {
    return Promise.reject({ Error: 'Something Went Wrong', err });

How do you use $sce.trustAsHtml(string) to replicate ng-bind-html-unsafe in Angular 1.2+

If you want the old directive back, you can add this to your app:


directives.directive('ngBindHtmlUnsafe', ['$sce', function($sce){
    return {
        scope: {
            ngBindHtmlUnsafe: '=',
        template: "<div ng-bind-html='trustedHtml'></div>",
        link: function($scope, iElm, iAttrs, controller) {
            $scope.updateView = function() {
                $scope.trustedHtml = $sce.trustAsHtml($scope.ngBindHtmlUnsafe);

            $scope.$watch('ngBindHtmlUnsafe', function(newVal, oldVal) {


<div ng-bind-html-unsafe="group.description"></div>

Source -

Why can't I define my workbook as an object?

You'll need to open the workbook to refer to it.

Sub Setwbk()

    Dim wbk As Workbook

    Set wbk = Workbooks.Open("F:\Quarterly Reports\2012 Reports\New Reports\ _
        Master Benchmark Data Sheet.xlsx")

End Sub

* Follow Doug's answer if the workbook is already open. For the sake of making this answer as complete as possible, I'm including my comment on his answer:

Why do I have to "set" it?

Set is how VBA assigns object variables. Since a Range and a Workbook/Worksheet are objects, you must use Set with these.

No newline after div?

This works the best, in my case, I tried it all

.div_class {
    clear: left;

Hide text within HTML?

You said that you can’t use HTML comments because the CMS filters them out. So I assume that you really want to hide this content and you don’t need to display it ever.

In that case, you shouldn’t use CSS (only), as you’d only play on the presentation level, not affecting the content level. Your content should also be hidden for user-agents ignoring the CSS (people using text browsers, feed readers, screen readers; bots; etc.).

In HTML5 there is the global hidden attribute:

When specified on an element, it indicates that the element is not yet, or is no longer, directly relevant to the page's current state, or that it is being used to declare content to be reused by other parts of the page as opposed to being directly accessed by the user. User agents should not render elements that have the hidden attribute specified.

Example (using the small element here, because it’s an "attribution"):

<small hidden>Thanks to John Doe for this idea.</small>

As a fallback (for user-agents that don’t know the hidden attribute), you can specify in your CSS:

[hidden] {display:none;}

An general element for plain text could be the script element used as "data block":

<script type="text/plain" hidden>
Thanks to John Doe for this idea.

Alternatively, you could also use data-* attributes on existing elements (resp. on new div elements if you want to group some elements for the attribution):

<p data-attribution="Thanks to John Doe for this idea!">This is some visible example content …</p>

How can I mock an ES6 module import using Jest?

The claims that you have to mock it at the top of your file are false.

Mock a named ES Import:

// import the named module
import { useWalkthroughAnimations } from '../hooks/useWalkthroughAnimations';

// mock the file and its named export
jest.mock('../hooks/useWalkthroughAnimations', () => ({
  useWalkthroughAnimations: jest.fn()

// do whatever you need to do with your mocked function
useWalkthroughAnimations.mockReturnValue({ pageStyles, goToNextPage, page });

Writing JSON object to a JSON file with fs.writeFileSync

You need to stringify the object.

fs.writeFileSync('../data/phraseFreqs.json', JSON.stringify(output));

How do I find the PublicKeyToken for a particular dll?

Just adding more info, I wasn't able to find sn.exe utility in the mentioned locations, in my case it was in C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\bin

What is ":-!!" in C code?

Some people seem to be confusing these macros with assert().

These macros implement a compile-time test, while assert() is a runtime test.

How to use sudo inside a docker container?

Just got it. As regan pointed out, I had to add the user to the sudoers group. But the main reason was I'd forgotten to update the repositories cache, so apt-get couldn't find the sudo package. It's working now. Here's the completed code:

FROM ubuntu:12.04

RUN apt-get update && \
      apt-get -y install sudo

RUN useradd -m docker && echo "docker:docker" | chpasswd && adduser docker sudo

USER docker
CMD /bin/bash

How to create string with multiple spaces in JavaScript

You can use the <pre> tag with innerHTML. The HTML <pre> element represents preformatted text which is to be presented exactly as written in the HTML file. The text is typically rendered using a non-proportional ("monospace") font. Whitespace inside this element is displayed as written. If you don't want a different font, simply add pre as a selector in your CSS file and style it as desired.


var a = '<pre>something        something</pre>';
document.body.innerHTML = a;

Trusting all certificates using HttpClient over HTTPS

For those who would like to allow all certificates to work (for testing purposes) over OAuth, follow these steps:

1) Download the source code of the Android OAuth API here:

2) Find the file "CommonsHttpOAuthProvider" class

3) Change it as below:

public class CommonsHttpOAuthProvider extends AbstractOAuthProvider {

private static final long serialVersionUID = 1L;

private transient HttpClient httpClient;

public CommonsHttpOAuthProvider(String requestTokenEndpointUrl, String accessTokenEndpointUrl,
        String authorizationWebsiteUrl) {
    super(requestTokenEndpointUrl, accessTokenEndpointUrl, authorizationWebsiteUrl);

    //this.httpClient = new DefaultHttpClient();//Version implemented and that throws the famous " Not trusted server certificate" if the certificate is not signed with a CA
    this.httpClient = MySSLSocketFactory.getNewHttpClient();//This will work with all certificates (for testing purposes only)

The "MySSLSocketFactory" above is based on the accepted answer. To make it even easier, here goes the complete class:

package com.netcomps.oauth_example;



import org.apache.http.HttpVersion;
import org.apache.http.client.HttpClient;
import org.apache.http.conn.ClientConnectionManager;
import org.apache.http.conn.scheme.PlainSocketFactory;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.scheme.SchemeRegistry;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.HTTP;

public class MySSLSocketFactory extends SSLSocketFactory {

    SSLContext sslContext = SSLContext.getInstance("TLS");

public MySSLSocketFactory(KeyStore truststore) throws NoSuchAlgorithmException, KeyManagementException, KeyStoreException, UnrecoverableKeyException {

    TrustManager tm = new X509TrustManager() {

        public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {

        public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {

        public X509Certificate[] getAcceptedIssuers() {
            return null;

    sslContext.init(null, new TrustManager[] { tm }, null);

public Socket createSocket(Socket socket, String host, int port, boolean autoClose) throws IOException, UnknownHostException {
    return sslContext.getSocketFactory().createSocket(socket, host, port, autoClose);

public Socket createSocket() throws IOException {
    return sslContext.getSocketFactory().createSocket();

public static HttpClient getNewHttpClient() {

    try {
        KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
        trustStore.load(null, null);

        SSLSocketFactory sf = new MySSLSocketFactory(trustStore);

        HttpParams params = new BasicHttpParams();
        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
        HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);

        SchemeRegistry registry = new SchemeRegistry();
        registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
        registry.register(new Scheme("https", sf, 443));

        ClientConnectionManager ccm = new ThreadSafeClientConnManager(params, registry);

        return new DefaultHttpClient(ccm, params);

    } catch (Exception e) {
        return new DefaultHttpClient();


Hope this helps someone.

"int cannot be dereferenced" in Java




id == list[pos].getItemNumber()

For more details, you should learn the difference between the primitive types like int, char, and double and reference types.

How can I rotate an HTML <div> 90 degrees?

Use following in your CSS

div {
    -webkit-transform: rotate(90deg); /* Safari and Chrome */
    -moz-transform: rotate(90deg);   /* Firefox */
    -ms-transform: rotate(90deg);   /* IE 9 */
    -o-transform: rotate(90deg);   /* Opera */
    transform: rotate(90deg);

Run exe file with parameters in a batch file

This should work:

start "" "c:\program files\php\php.exe" D:\mydocs\mp\index.php param1 param2

The start command interprets the first argument as a window title if it contains spaces. In this case, that means start considers your whole argument a title and sees no command. Passing "" (an empty title) as the first argument to start fixes the problem.

DLL References in Visual C++

The additional include directories are relative to the project dir. This is normally the dir where your project file, *.vcproj, is located. I guess that in your case you have to add just "include" to your include and library directories.

If you want to be sure what your project dir is, you can check the value of the $(ProjectDir) macro. To do that go to "C/C++ -> Additional Include Directories", press the "..." button and in the pop-up dialog press "Macros>>".