Programs & Examples On #Defaultnetworkcredentials

A property of Microsoft's .NET Framework that returns the security context of the current user or application.

How to set username and password for SmtpClient object in .NET?

The SmtpClient can be used by code:

SmtpClient mailer = new SmtpClient();
mailer.Host = "";
mailer.Credentials = new System.Net.NetworkCredential("yourusername", "yourpassword");

How to save/restore serializable object to/from file?

You can use the following:

    /// <summary>
    /// Serializes an object.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="serializableObject"></param>
    /// <param name="fileName"></param>
    public void SerializeObject<T>(T serializableObject, string fileName)
        if (serializableObject == null) { return; }

            XmlDocument xmlDocument = new XmlDocument();
            XmlSerializer serializer = new XmlSerializer(serializableObject.GetType());
            using (MemoryStream stream = new MemoryStream())
                serializer.Serialize(stream, serializableObject);
                stream.Position = 0;
        catch (Exception ex)
            //Log exception here

    /// <summary>
    /// Deserializes an xml file into an object list
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="fileName"></param>
    /// <returns></returns>
    public T DeSerializeObject<T>(string fileName)
        if (string.IsNullOrEmpty(fileName)) { return default(T); }

        T objectOut = default(T);

            XmlDocument xmlDocument = new XmlDocument();
            string xmlString = xmlDocument.OuterXml;

            using (StringReader read = new StringReader(xmlString))
                Type outType = typeof(T);

                XmlSerializer serializer = new XmlSerializer(outType);
                using (XmlReader reader = new XmlTextReader(read))
                    objectOut = (T)serializer.Deserialize(reader);
        catch (Exception ex)
            //Log exception here

        return objectOut;

Using JSON POST Request

Modern browsers do not currently implement JSONRequest (as far as I know) since it is only a draft right now. I have found someone who has implemented it as a library that you can include in your page: (please note that it has a few dependencies).

Otherwise, you might want to go with another JS library like jQuery or Mootools.

Pass request headers in a jQuery AJAX GET call

As of jQuery 1.5, there is a headers hash you can pass in as follows:

    url: "/test",
    headers: {"X-Test-Header": "test-value"}


headers (added 1.5): A map of additional header key/value pairs to send along with the request. This setting is set before the beforeSend function is called; therefore, any values in the headers setting can be overwritten from within the beforeSend function.

Find the division remainder of a number

If you want to get quotient and remainder in one line of code (more general usecase), use:

quotient, remainder = divmod(dividend, divisor)
divmod(26, 7)

JavaScript DOM remove element

removeChild should be invoked on the parent, i.e.:


In your example, you should be doing something like:

if (frameid) {

How do I calculate the MD5 checksum of a file in Python?

In regards to your error and what's missing in your code. m is a name which is not defined for getmd5() function.

No offence, I know you are a beginner, but your code is all over the place. Let's look at your issues one by one :)

First, you are not using hashlib.md5.hexdigest() method correctly. Please refer explanation on hashlib functions in Python Doc Library. The correct way to return MD5 for provided string is to do something like this:

>>> import hashlib
>>> hashlib.md5("filename.exe").hexdigest()

However, you have a bigger problem here. You are calculating MD5 on a file name string, where in reality MD5 is calculated based on file contents. You will need to basically read file contents and pipe it though MD5. My next example is not very efficient, but something like this:

>>> import hashlib
>>> hashlib.md5(open('filename.exe','rb').read()).hexdigest()

As you can clearly see second MD5 hash is totally different from the first one. The reason for that is that we are pushing contents of the file through, not just file name.

A simple solution could be something like that:

# Import hashlib library (md5 method is part of it)
import hashlib

# File to check
file_name = 'filename.exe'

# Correct original md5 goes here
original_md5 = '5d41402abc4b2a76b9719d911017c592'  

# Open,close, read file and calculate MD5 on its contents 
with open(file_name) as file_to_check:
    # read contents of the file
    data =    
    # pipe contents of the file through
    md5_returned = hashlib.md5(data).hexdigest()

# Finally compare original MD5 with freshly calculated
if original_md5 == md5_returned:
    print "MD5 verified."
    print "MD5 verification failed!."

Please look at the post Python: Generating a MD5 checksum of a file. It explains in detail a couple of ways how it can be achieved efficiently.

Best of luck.

Create array of all integers between two numbers, inclusive, in Javascript/jQuery

Solving in underscore

data = [];
_.times( highEnd, function( n ){ data.push( lowEnd ++ ) } );

ImportError: No module named sklearn.cross_validation

It must relate to the renaming and deprecation of cross_validation sub-module to model_selection. Try substituting cross_validation to model_selection

How can I set the PATH variable for javac so I can manually compile my .java works?

Follow the steps given here

after setting variable, just navigate to your java file directory in your cmd and type javac ""

or if you don't navigate to the directory, then simply specify the full path of java file

javac "/"

Regex any ASCII character

Since US-ASCII characters are in the byte range of 0x00–0x7F (0–127):


How to specify jdk path in eclipse.ini on windows 8 when path contains space

Go to C drive root in cmd Type dir /x This will list down the directories name with ~.use that instead of Program Files in your jdk path

installing requests module in python 2.7 windows

  1. Download the source code(zip or rar package).
  2. Run the inside.

How do I make a delay in Java?

Use Thread.sleep(1000);

1000 is the number of milliseconds that the program will pause.

catch(InterruptedException ex)

IOS 7 Navigation Bar text and arrow color

Swift 5/iOS 13

To change color of title in controller:

UINavigationBar.appearance().titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.white]

How can I get color-int from color resource?

Define your color


<?xml version="1.0" encoding="utf-8"?>

    <!-- color int as #AARRGGBB (alpha, red, green, blue) -->
    <color name="orange">#fff3632b</color>
    <color name="my_view_color">@color/orange</color>


Get the color int and set it

int backgroundColor = ContextCompat.getColor(context, R.color.my_view_color);
// Color backgroundColor = ... (Don't do this. The color is just an int.)


See also

Is there a way to get the source code from an APK file?

The simplest way is using Apk OneClick Decompiler. That is a tool package to decompile & disassemble APKs (android packages).


  • All features are integrated into the right-click menu of Windows.
  • Decompile APK classes to Java source codes.
  • Disassemble APK to smali code and decode its resources.
  • Install APK to phone by right-click.
  • Recompile APK after editing smali code and/or resources. During recompile:
  • Optimize png images
  • Sign apks
  • Zipalign


Java Runtime Environment (JRE) must be installed.

You can download it from this link Apk OneClick Decompiler

Enjoy that.

How to install a PHP IDE plugin for Eclipse directly from the Eclipse environment?

The new URL for the repository is now In Eclipse: open Help -> install new sofware -> add. Then paste this URL in the location.

Mark the check boxes you want and click next.

What is “2's Complement”?

Like most explanations I've seen, the ones above are clear about how to work with 2's complement, but don't really explain what they are mathematically. I'll try to do that, for integers at least, and I'll cover some background that's probably familiar first.

Recall how it works for decimal:
is a way of writing
  2 × 103 + 3 × 102 + 4 × 101 + 5 × 100.

In the same way, binary is a way of writing numbers using just 0 and 1 following the same general idea, but replacing those 10s above with 2s. Then in binary,
is a way of writing
  1 × 23 + 1 × 22 + 1 × 21 + 1 × 20
and if you work it out, that turns out to equal 15 (base 10). That's because it is
  8+4+2+1 = 15.

This is all well and good for positive numbers. It even works for negative numbers if you're willing to just stick a minus sign in front of them, as humans do with decimal numbers. That can even be done in computers, sort of, but I haven't seen such a computer since the early 1970's. I'll leave the reasons for a different discussion.

For computers it turns out to be more efficient to use a complement representation for negative numbers. And here's something that is often overlooked. Complement notations involve some kind of reversal of the digits of the number, even the implied zeroes that come before a normal positive number. That's awkward, because the question arises: all of them? That could be an infinite number of digits to be considered.

Fortunately, computers don't represent infinities. Numbers are constrained to a particular length (or width, if you prefer). So let's return to positive binary numbers, but with a particular size. I'll use 8 digits ("bits") for these examples. So our binary number would really be
  0 × 27 + 0 × 26 + 0 × 25 + 0 × 24 + 1 × 23 + 1 × 22 + 1 × 21 + 1 × 20

To form the 2's complement negative, we first complement all the (binary) digits to form
and add 1 to form
but how are we to understand that to mean -15?

The answer is that we change the meaning of the high-order bit (the leftmost one). This bit will be a 1 for all negative numbers. The change will be to change the sign of its contribution to the value of the number it appears in. So now our 11110001 is understood to represent
  -1 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 0 × 23 + 0 × 22 + 0 × 21 + 1 × 20
Notice that "-" in front of that expression? It means that the sign bit carries the weight -27, that is -128 (base 10). All the other positions retain the same weight they had in unsigned binary numbers.

Working out our -15, it is
  -128 + 64 + 32 + 16 + 1
Try it on your calculator. it's -15.

Of the three main ways that I've seen negative numbers represented in computers, 2's complement wins hands down for convenience in general use. It has an oddity, though. Since it's binary, there have to be an even number of possible bit combinations. Each positive number can be paired with its negative, but there's only one zero. Negating a zero gets you zero. So there's one more combination, the number with 1 in the sign bit and 0 everywhere else. The corresponding positive number would not fit in the number of bits being used.

What's even more odd about this number is that if you try to form its positive by complementing and adding one, you get the same negative number back. It seems natural that zero would do this, but this is unexpected and not at all the behavior we're used to because computers aside, we generally think of an unlimited supply of digits, not this fixed-length arithmetic.

This is like the tip of an iceberg of oddities. There's more lying in wait below the surface, but that's enough for this discussion. You could probably find more if you research "overflow" for fixed-point arithmetic. If you really want to get into it, you might also research "modular arithmetic".

Your configuration specifies to merge with the <branch name> from the remote, but no such ref was fetched.?

I just got exactly this error when doing "git pull" when my disk was full. Created some space and it all started working fine again.

Getting time span between two times in C#?

You could use the TimeSpan constructor which takes a long for Ticks:

 TimeSpan duration = new TimeSpan(endtime.Ticks - startTime.Ticks);

Where can I find Android's default icons?

you can use

(use autocomplete to see whats in there)

Or download the stuff from

How does Spring autowire by name when more than one matching bean is found?

This is documented in section 3.9.3 of the Spring 3.0 manual:

For a fallback match, the bean name is considered a default qualifier value.

In other words, the default behaviour is as though you'd added @Qualifier("country") to the setter method.

Can anyone confirm that phpMyAdmin AllowNoPassword works with MySQL databases?

  1. Copy to

    In most cases you will find the config file

    • on linux: /etc/phpmyadmin/
    • on mac: /Library/WebServer/Documents/phpmyadmin/
  2. If you are trying to log in as root, you should have the following lines in your config:

    $cfg['Servers'][$i]['user'] = 'root';
    $cfg['Servers'][$i]['AllowNoPassword'] = true;

Environ Function code samples for VBA

Some time when we use Environ() function we may get the Library or property not found error. Use VBA.Environ() or VBA.Environ$() to avoid the error.

global variable for all controller and views

In Laravel 5.1 I needed a global variable populated with model data accessible in all views.

I followed a similar approach to ollieread's answer and was able to use my variable ($notifications) in any view.

My controller location: /app/Http/Controllers/Controller.php


namespace App\Http\Controllers;

use Illuminate\Foundation\Bus\DispatchesJobs;
use Illuminate\Routing\Controller as BaseController;
use Illuminate\Foundation\Validation\ValidatesRequests;
use Illuminate\Foundation\Auth\Access\AuthorizesRequests;

use App\Models\Main as MainModel;
use View;

abstract class Controller extends BaseController
    use AuthorizesRequests, DispatchesJobs, ValidatesRequests;

    public function __construct() {
        $oMainM = new MainModel;
        $notifications = $oMainM->get_notifications();
        View::share('notifications', $notifications);

My model location: /app/Models/Main.php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use DB;

class Main extends Model
    public function get_notifications() {...

Home does not contain an export named Home

I just ran into this error message (after upgrading to nextjs 9 some transpiled imports started giving this error). I managed to fix them using syntax like this:

import * as Home from './layouts/Home';

Update my gradle dependencies in eclipse

I tried all above options but was still getting error, in my case issue was I have not setup gradle installation directory in eclipse, following worked:

eclipse -> Window -> Preferences -> Gradle -> "Select Local Installation Directory"

Click on Browse button and provide path.

Even though question is answered, thought to share in case somebody else is facing similar issue.

Cheers !

Java 8 List<V> into Map<K, V>

Map<String, Set<String>> collect = Arrays.asList(Locale.getAvailableLocales()).stream().collect(Collectors
                .toMap(l -> l.getDisplayCountry(), l -> Collections.singleton(l.getDisplayLanguage())));

Days between two dates?



I tried with b and a of type

Can a java lambda have more than 1 parameter?

Another alternative, not sure if this applies to your particular problem but to some it may be applicable is to use UnaryOperator in java.util.function library. where it returns same type you specify, so you put all your variables in one class and is it as a parameter:

public class FunctionsLibraryUse {

    public static void main(String[] args){
        UnaryOperator<People> personsBirthday = (p) ->{
            System.out.println("it's " + p.getName() + " birthday!");
            p.setAge(p.getAge() + 1);
            return p;
        People mel = new People();
        mel = personsBirthday.apply(mel);
        System.out.println("he is now : " + mel.getAge());

class People{
    private String name;
    private int age;
    public String getName() {
        return name;
    public void setName(String name) { = name;
    public int getAge() {
        return age;
    public void setAge(int age) {
        this.age = age;

So the class you have, in this case Person, can have numerous instance variables and won't have to change the parameter of your lambda expression.

For those interested, I've written notes on how to use java.util.function library:

oracle diff: how to compare two tables?

You can try using set operations: MINUS and INTERSECT

See here for more details:
O'Reilly - Mastering Oracle SQL - Chapter 7 - Set Operations

Spring get current ApplicationContext

Step 1 :Inject following code in class

private ApplicationContext _applicationContext;

Step 2 : Write Getter & Setter

Step 3: define autowire="byType" in xml file in which bean is defined

Remove CSS class from element with JavaScript (no jQuery)

Here's a way to bake this functionality right into all DOM elements:

HTMLElement.prototype.removeClass = function(remove) {
    var newClassName = "";
    var i;
    var classes = this.className.split(" ");
    for(i = 0; i < classes.length; i++) {
        if(classes[i] !== remove) {
            newClassName += classes[i] + " ";
    this.className = newClassName;

HashMap to return default value for non-found keys?

In mixed Java/Kotlin projects also consider Kotlin's Map.withDefault.

How to retrieve raw post data from HttpServletRequest in java

The request body is available as byte stream by HttpServletRequest#getInputStream():

InputStream body = request.getInputStream();
// ...

Or as character stream by HttpServletRequest#getReader():

Reader body = request.getReader();
// ...

Note that you can read it only once. The client ain't going to resend the same request multiple times. Calling getParameter() and so on will implicitly also read it. If you need to break down parameters later on, you've got to store the body somewhere and process yourself.

Getting absolute URLs using ASP.NET Core

You can get the url like this:



The Request.UrlReferer will throw a System.UriFormatException if the referer HTTP header is malformed (which can happen since it is not usually under your control).

As for using Request.ServerVariables, per MSDN:

Request.ServerVariables Collection

The ServerVariables collection retrieves the values of predetermined environment variables and request header information.

Request.Headers Property

Gets a collection of HTTP headers.

I guess I don't understand why you would prefer the Request.ServerVariables over Request.Headers, since Request.ServerVariables contains all of the environment variables as well as the headers, where Request.Headers is a much shorter list that only contains the headers.

So the best solution is to use the Request.Headers collection to read the value directly. Do heed Microsoft's warnings about HTML encoding the value if you are going to display it on a form, though.

How to use Chrome's network debugger with redirects

Just update of @bfncs answer

I think around Chrome 43 the behavior was changed a little. You still need to enable Preserve log to see, but now redirect shown under Other tab, when loaded document is shown under Doc.

This always confuse me, because I have a lot of networks requests and filter it by type XHR, Doc, JS etc. But in case of redirect the Doc tab is empty, so I have to guess.

android edittext onchange listener

As far as I can think bout it, there's only two ways you can do it. How can you know the user has finished writing a word? Either on focus lost, or clicking on an "ok" button. There's no way on my mind you can know the user pressed the last character...

So call onFocusChange(View v, boolean hasFocus) or add a button and a click listener to it.

Two Divs next to each other, that then stack with responsive change

Do like this:


<div class="parent">
    <div class="child"></div>
    <div class="child"></div>


    width: 400px;
    background: red;
    float: left;
    height: 100px;

This is working jsfiddle. Change child width to more then 200px and they will stack.

Android Webview - Completely Clear the Cache

use case: list of item are displaying in recycler view, whenever any item click it hides recycler view and shows web view with item url.

problem: i have similar problem in which once i open a url_one in webview , then try to open another url_two in webview, it shows url_one in background till url_two is loaded.

solution: so to solve what i did is load blank string "" as url just before hiding url_one and loading url_two.

output: whenever i load any new url in webview it does not show any other web page in background.


public void showWebView(String url){

public void onListItemClick(String url){

public void hideWebView(){
        // loading blank url so it overrides last open url

public void onBackPressed() {
    if(webView.getVisibility() == View.VISIBLE){

Using scp to copy a file to Amazon EC2 instance?

You should be on you local machine to try the above scp command.

On your local machine try:

scp -i ~/Downloads/myAmazonKey.pem ~/Downloads/phpMyAdmin-3.4.5-all-languages.tar.gz  [email protected]:~/.

Rendering partial view on button click in ASP.NET MVC

Change the button to

<button id="search">Search</button>

and add the following script

var url = '@Url.Action("DisplaySearchResults", "Search")';
$('#search').click(function() {
  var keyWord = $('#Keyword').val();
  $('#searchResults').load(url, { searchText: keyWord });

and modify the controller method to accept the search text

public ActionResult DisplaySearchResults(string searchText)
  var model = // build list based on parameter searchText
   return PartialView("SearchResults", model);

The jQuery .load method calls your controller method, passing the value of the search text and updates the contents of the <div> with the partial view.

Side note: The use of a <form> tag and @Html.ValidationSummary() and @Html.ValidationMessageFor() are probably not necessary here. Your never returning the Index view so ValidationSummary makes no sense and I assume you want a null search text to return all results, and in any case you do not have any validation attributes for property Keyword so there is nothing to validate.


Based on OP's comments that SearchCriterionModel will contain multiple properties with validation attributes, then the approach would be to include a submit button and handle the forms .submit() event

<input type="submit" value="Search" />

var url = '@Url.Action("DisplaySearchResults", "Search")';
$('form').submit(function() {
  if (!$(this).valid()) { 
    return false; // prevent the ajax call if validation errors
  var form = $(this).serialize();
  $('#searchResults').load(url, form);
  return false; // prevent the default submit action

and the controller method would be

public ActionResult DisplaySearchResults(SearchCriterionModel criteria)
  var model = // build list based on the properties of criteria
  return PartialView("SearchResults", model);

Regex: matching up to the first occurrence of a character

None of the proposed answers did work for me. (e.g. in notepad++) But



SQL Server Management Studio missing

If you have a copy of backup of SQL Server setup then you could add features (Management Tools Basic/Complete) as you requested.

Please use the below steps in Windows machine:

  1. Go to Control Panel -> Programs -> Program and Features -> Select your current version of Microsoft SQL Server
  2. Right Click, select Change/Uninstall
  3. Click Add features
  4. Select the backup copy folder
  5. Do the steps what you done for SQL Server installation until features selection
  6. Now select the features Management Tools Basic/Complete or both
  7. And go ahead with process for complete installation.
  8. Now you should get, SQL Server Management Studio and you can browse your databases.

Insert text into textarea with jQuery

If you want to append content to the textarea without replacing them, You can try the below

$('textarea').append('Whatever need to be added');

According to your scenario it would be


Getting Python error "from: can't read /var/mail/Bio"

I ran into a similar error

"from: can't read /var/mail/django.test.utils"

when trying to run a command

>>> from django.test.utils import setup_test_environment
>>> setup_test_environment()

in the tutorial at

after reading the answer by Tamás I realized I was not trying this command in the python shell but in the termnial (this can happen to those new to linux)

solution was to first enter in the python shell with the command python and when you get these >>> then run any python commands

Is it necessary to use # for creating temp tables in SQL server?

Yes. You need to prefix the table name with "#" (hash) to create temporary tables.

If you do NOT need the table later, go ahead & create it. Temporary Tables are very much like normal tables. However, it gets created in tempdb. Also, it is only accessible via the current session i.e. For EG: if another user tries to access the temp table created by you, he'll not be able to do so.

"##" (double-hash creates "Global" temp table that can be accessed by other sessions as well.

Refer the below link for the Basics of Temporary Tables:

If the content of your table is less than 5000 rows & does NOT contain data types such as nvarchar(MAX), varbinary(MAX), consider using Table Variables.

They are the fastest as they are just like any other variables which are stored in the RAM. They are stored in tempdb as well, not in RAM.

 column1 int,
 column2 int,
 someInt int,
 someVarChar nvarchar(50)

SELECT column1, 
  FROM table2
 WHERE table2.ID = 7;

More Info on Table Variables:

Converting double to integer in Java

Double perValue = 96.57;
int roundVal= (int) Math.round(perValue);

Solved my purpose.

JavaScript: What are .extend and .prototype used for?

  • .extends() create a class which is a child of another class.
    behind the scenes Child.prototype.__proto__ sets its value to Parent.prototype
    so methods are inherited.
  • .prototype inherit features from one to another.
  • .__proto__ is a getter/setter for Prototype.

How to detect when facebook's FB.init is complete

While some of the above solutions work, I thought I'd post our eventual solution - which defines a 'ready' method that will fire as soon as FB is initialized and ready to go. It has the advantage over other solutions that it's safe to call either before or after FB is ready.

It can be used like so:

f52.fb.ready(function() {
    // safe to use FB here

Here's the source file (note that it's defined within a 'f52.fb' namespace).

if (typeof(f52) === 'undefined') { f52 = {}; }
f52.fb = (function () {

    var fbAppId = f52.inputs.base.fbAppId,
        fbApiInit = false;

    var awaitingReady = [];

    var notifyQ = function() {
        var i = 0,
            l = awaitingReady.length;
        for(i = 0; i < l; i++) {

    var ready = function(cb) {
        if (fbApiInit) {
        } else {

    window.fbAsyncInit = function() {
            appId: fbAppId,
            xfbml: true,
            version: 'v2.0'

            fbApiInit = true;

    return {
         * Fires callback when FB is initialized and ready for api calls.
        'ready': ready


How to Get Element By Class in JavaScript?

This should work in pretty much any browser...

function getByClass (className, parent) {
  parent || (parent=document);
  var descendants=parent.getElementsByTagName('*'), i=-1, e, result=[];
  while (e=descendants[++i]) {
    ((' '+(e['class']||e.className)+' ').indexOf(' '+className+' ') > -1) && result.push(e);
  return result;

You should be able to use it like this:

function replaceInClass (className, content) {
  var nodes = getByClass(className), i=-1, node;
  while (node=nodes[++i]) node.innerHTML = content;

Adding new column to existing DataFrame in Python pandas

If you get the SettingWithCopyWarning, an easy fix is to copy the DataFrame you are trying to add a column to.

df = df.copy()
df['col_name'] = values

Is Secure.ANDROID_ID unique for each device?

String myID;
int myversion = 0;

myversion = Integer.valueOf(android.os.Build.VERSION.SDK);
if (myversion < 23) {
        TelephonyManager mngr = (TelephonyManager) 
        myID= mngr.getDeviceId();
        myID = 

Yes, Secure.ANDROID_ID is unique for each device.

Calling a JavaScript function returned from an Ajax response

I think to correctly interpret your question under this form: "OK, I'm already done with all the Ajax stuff; I just wish to know if the JavaScript function my Ajax callback inserted into the DIV is callable at any time from that moment on, that is, I do not want to call it contextually to the callback return".

OK, if you mean something like this the answer is yes, you can invoke your new code by that moment at any time during the page persistence within the browser, under the following conditions:

1) Your JavaScript code returned by Ajax callback must be syntactically OK;
2) Even if your function declaration is inserted into a <script> block within an existing <div> element, the browser won't know the new function exists, as the declaration code has never been executed. So, you must eval() your declaration code returned by the Ajax callback, in order to effectively declare your new function and have it available during the whole page lifetime.

Even if quite dummy, this code explains the idea:

        <div id="div1">
        <div id="div2">
            <input type="button" value="Go!" onclick="go()" />
        <script type="text/javascript">
            var newsc = '<script id="sc1" type="text/javascript">function go() { alert("GO!") }<\/script>';
            var e = document.getElementById('div1');
            e.innerHTML = newsc;

I didn't use Ajax, but the concept is the same (even if the example I chose sure isn't much smart :-)

Generally speaking, I do not question your solution design, i.e. whether it is more or less appropriate to externalize + generalize the function in a separate .js file and the like, but please take note that such a solution could raise further problems, especially if your Ajax invocations should repeat, i.e. if the context of the same function should change or in case the declared function persistence should be concerned, so maybe you should seriously consider to change your design to one of the suggested examples in this thread.

Finally, if I misunderstood your question, and you're talking about contextual invocation of the function when your Ajax callback returns, then my feeling is to suggest the Prototype approach described by krosenvold, as it is cross-browser, tested and fully functional, and this can give you a better roadmap for future implementations.

How to add a local repo and treat it as a remote repo

You have your arguments to the remote add command reversed:

git remote add <NAME> <PATH>


git remote add bak /home/sas/dev/apps/smx/repo/bak/ontologybackend/.git

See git remote --help for more information.

How do the likely/unlikely macros in the Linux kernel work and what is their benefit?

These are GCC functions for the programmer to give a hint to the compiler about what the most likely branch condition will be in a given expression. This allows the compiler to build the branch instructions so that the most common case takes the fewest number of instructions to execute.

How the branch instructions are built are dependent upon the processor architecture.

Generic List - moving an item within the list

Simplest way:

list[newIndex] = list[oldIndex];


The question isn't very clear ... Since we don't care where the list[newIndex] item goes I think the simplest way of doing this is as follows (with or without an extension method):

    public static void Move<T>(this List<T> list, int oldIndex, int newIndex)
        T aux = list[newIndex];
        list[newIndex] = list[oldIndex];
        list[oldIndex] = aux;

This solution is the fastest because it doesn't involve list insertions/removals.

Rock, Paper, Scissors Game Java

Before we try to solve the invalid character problem, the lack of curly braces around the if and else if statements is wreaking havoc on your program's logic. Change it to this:

if (personPlay.equals(computerPlay)) {
   System.out.println("It's a tie!");
else if (personPlay.equals("R")) {
   if (computerPlay.equals("S")) 
      System.out.println("Rock crushes scissors. You win!!");
   else if (computerPlay.equals("P")) 
        System.out.println("Paper eats rock. You lose!!");
else if (personPlay.equals("P")) {
   if (computerPlay.equals("S")) 
       System.out.println("Scissor cuts paper. You lose!!"); 
   else if (computerPlay.equals("R")) 
        System.out.println("Paper eats rock. You win!!");
else if (personPlay.equals("S")) {
     if (computerPlay.equals("P")) 
         System.out.println("Scissor cuts paper. You win!!"); 
     else if (computerPlay.equals("R")) 
        System.out.println("Rock breaks scissors. You lose!!");
     System.out.println("Invalid user input.");

Much clearer! It's now actually a piece of cake to catch the bad characters. You need to move the else statement to somewhere that will catch the errors before you attempt to process anything else. So change everything to:

if( /* insert your check for bad characters here */ ) { 
     System.out.println("Invalid user input.");
else if (personPlay.equals(computerPlay)) {
   System.out.println("It's a tie!");
else if (personPlay.equals("R")) {
   if (computerPlay.equals("S")) 
      System.out.println("Rock crushes scissors. You win!!");
   else if (computerPlay.equals("P")) 
        System.out.println("Paper eats rock. You lose!!");
else if (personPlay.equals("P")) {
   if (computerPlay.equals("S")) 
       System.out.println("Scissor cuts paper. You lose!!"); 
   else if (computerPlay.equals("R")) 
        System.out.println("Paper eats rock. You win!!");
else if (personPlay.equals("S")) {
     if (computerPlay.equals("P")) 
         System.out.println("Scissor cuts paper. You win!!"); 
     else if (computerPlay.equals("R")) 
        System.out.println("Rock breaks scissors. You lose!!");

How can I find an element by CSS class with XPath?

This selector should work but will be more efficient if you replace it with your suited markup:

//*[contains(@class, 'Test')]

Or, since we know the sought element is a div:

//div[contains(@class, 'Test')]

But since this will also match cases like class="Testvalue" or class="newTest", @Tomalak's version provided in the comments is better:

//div[contains(concat(' ', @class, ' '), ' Test ')]

If you wished to be really certain that it will match correctly, you could also use the normalize-space function to clean up stray whitespace characters around the class name (as mentioned by @Terry):

//div[contains(concat(' ', normalize-space(@class), ' '), ' Test ')]

Note that in all these versions, the * should best be replaced by whatever element name you actually wish to match, unless you wish to search each and every element in the document for the given condition.

Get domain name

I know this is old. I just wanted to dump this here for anyone that was looking for an answer to getting a domain name. This is in coordination with Peter's answer. There "is" a bug as stated by Rich. But, you can always make a simple workaround for that. The way I can tell if they are still on the domain or not is by pinging the domain name. If it responds, continue on with whatever it was that I needed the domain for. If it fails, I drop out and go into "offline" mode. Simple string method.

 string GetDomainName()
        string _domain = IPGlobalProperties.GetIPGlobalProperties().DomainName;

        Ping ping = new Ping();

            PingReply reply = ping.Send(_domain);

            if (reply.Status == IPStatus.Success)
                return _domain;
                return reply.Status.ToString();
        catch (PingException pExp)
            if (pExp.InnerException.ToString() == "No such host is known")
                return "Network not detected!";

            return "Ping Exception";

Using Javascript's atob to decode base64 doesn't properly decode utf-8 strings

Things change. The escape/unescape methods have been deprecated.

You can URI encode the string before you Base64-encode it. Note that this does't produce Base64-encoded UTF8, but rather Base64-encoded URL-encoded data. Both sides must agree on the same encoding.

See working example here:

// encode string
var base64 = window.btoa(encodeURIComponent('€ ?? æøåÆØÅ'));
// decode string
var str = decodeURIComponent(window.atob(tmp));
// str is now === '€ ?? æøåÆØÅ'

For OP's problem a third party library such as js-base64 should solve the problem.

NSInternalInconsistencyException', reason: 'Could not load NIB in bundle: 'NSBundle

I tried several things, finally what worked for me was to delete (and move to trash) the .xib file in question. Then re-create it. To make things easier, I copied the stuff in the .xib temporarily to another .xib, then copied it back into the newly created one.


Try this:

=IF(NOT(ISERROR(MATCH(A3,worksheet2!A:A,0))),COUNTIF(worksheet2!A:A,A3),"No Match Found")

mailto link multiple body lines

  1. Use a single body parameter within the mailto string
  2. Use %0D%0A as newline

The mailto URI Scheme is specified by by RFC2368 (July 1998) and RFC6068 (October 2010).
Below is an extract of section 5 of this last RFC:

[...] line breaks in the body of a message MUST be encoded with "%0D%0A".
Implementations MAY add a final line break to the body of a message even if there is no trailing "%0D%0A" in the body [...]

See also in section 6 the example from the same RFC:

<mailto:[email protected]?body=send%20current-issue%0D%0Asend%20index>

The above mailto body corresponds to:

send current-issue
send index

Conversion of Char to Binary in C

We show up two functions that prints a SINGLE character to binary.

void printbinchar(char character)
    char output[9];
    itoa(character, output, 2);
    printf("%s\n", output);

printbinchar(10) will write into the console


itoa is a library function that converts a single integer value to a string with the specified base. For example... itoa(1341, output, 10) will write in output string "1341". And of course itoa(9, output, 2) will write in the output string "1001".

The next function will print into the standard output the full binary representation of a character, that is, it will print all 8 bits, also if the higher bits are zero.

void printbincharpad(char c)
    for (int i = 7; i >= 0; --i)
        putchar( (c & (1 << i)) ? '1' : '0' );

printbincharpad(10) will write into the console


Now i present a function that prints out an entire string (without last null character).

void printstringasbinary(char* s)
    // A small 9 characters buffer we use to perform the conversion
    char output[9];

    // Until the first character pointed by s is not a null character
    // that indicates end of string...
    while (*s)
        // Convert the first character of the string to binary using itoa.
        // Characters in c are just 8 bit integers, at least, in noawdays computers.
        itoa(*s, output, 2);

        // print out our string and let's write a new line.

        // we advance our string by one character,
        // If our original string was "ABC" now we are pointing at "BC".

Consider however that itoa don't adds padding zeroes, so printstringasbinary("AB1") will print something like:


Violation of PRIMARY KEY constraint. Cannot insert duplicate key in object

I was getting the same error on a restored database when I tried to insert a new record using the EntityFramework. It turned out that the Indentity/Seed was screwing things up.

Using a reseed command fixed it.

DBCC CHECKIDENT ('[Prices]', RESEED, 4747030);GO

Which variable size to use (db, dw, dd) with x86 assembly?

The full list is:

DB, DW, DD, DQ, DT, DDQ, and DO (used to declare initialized data in the output file.)


They can be invoked in a wide range of ways: (Note: for Visual-Studio - use "h" instead of "0x" syntax - eg: not 0x55 but 55h instead):

    db      0x55                ; just the byte 0x55
    db      0x55,0x56,0x57      ; three bytes in succession
    db      'a',0x55            ; character constants are OK
    db      'hello',13,10,'$'   ; so are string constants
    dw      0x1234              ; 0x34 0x12
    dw      'A'                 ; 0x41 0x00 (it's just a number)
    dw      'AB'                ; 0x41 0x42 (character constant)
    dw      'ABC'               ; 0x41 0x42 0x43 0x00 (string)
    dd      0x12345678          ; 0x78 0x56 0x34 0x12
    dq      0x1122334455667788  ; 0x88 0x77 0x66 0x55 0x44 0x33 0x22 0x11
    ddq     0x112233445566778899aabbccddeeff00
    ; 0x00 0xff 0xee 0xdd 0xcc 0xbb 0xaa 0x99
    ; 0x88 0x77 0x66 0x55 0x44 0x33 0x22 0x11
    do      0x112233445566778899aabbccddeeff00 ; same as previous
    dd      1.234567e20         ; floating-point constant
    dq      1.234567e20         ; double-precision float
    dt      1.234567e20         ; extended-precision float

DT does not accept numeric constants as operands, and DDQ does not accept float constants as operands. Any size larger than DD does not accept strings as operands.

Regular expression - starting and ending with a letter, accepting only letters, numbers and _

Here's a solution using a negative lookahead (not supported in all regex engines):


Test that it works as expected:

import re
tests = [
   ('a', True),
   ('_', False),
   ('zz', True),
   ('a0', True),
   ('A_', False),
   ('a0_b', True),
   ('a__b', False),
   ('a_1_c', True),

regex = '^[a-zA-Z](((?!__)[a-zA-Z0-9_])*[a-zA-Z0-9])?$'
for test in tests:
   is_match = re.match(regex, test[0]) is not None
   if is_match != test[1]:
       print "fail: "  + test[0]

<modules runAllManagedModulesForAllRequests="true" /> Meaning

Modules Preconditions:

The IIS core engine uses preconditions to determine when to enable a particular module. Performance reasons, for example, might determine that you only want to execute managed modules for requests that also go to a managed handler. The precondition in the following example (precondition="managedHandler") only enables the forms authentication module for requests that are also handled by a managed handler, such as requests to .aspx or .asmx files:

<add name="FormsAuthentication" type="System.Web.Security.FormsAuthenticationModule" preCondition="managedHandler" />

If you remove the attribute precondition="managedHandler", Forms Authentication also applies to content that is not served by managed handlers, such as .html, .jpg, .doc, but also for classic ASP (.asp) or PHP (.php) extensions. See "How to Take Advantage of IIS Integrated Pipeline" for an example of enabling ASP.NET modules to run for all content.

You can also use a shortcut to enable all managed (ASP.NET) modules to run for all requests in your application, regardless of the "managedHandler" precondition.

To enable all managed modules to run for all requests without configuring each module entry to remove the "managedHandler" precondition, use the runAllManagedModulesForAllRequests property in the <modules> section:

<modules runAllManagedModulesForAllRequests="true" />    

When you use this property, the "managedHandler" precondition has no effect and all managed modules run for all requests.

Copied from IIS Modules Overview: Preconditions

Best TCP port number range for internal applications

I can't see why you would care. Other than the "don't use ports below 1024" privilege rule, you should be able to use any port because your clients should be configurable to talk to any IP address and port!

If they're not, then they haven't been done very well. Go back and do them properly :-)

In other words, run the server at IP address X and port Y then configure clients with that information. Then, if you find you must run a different server on X that conflicts with your Y, just re-configure your server and clients to use a new port. This is true whether your clients are code, or people typing URLs into a browser.

I, like you, wouldn't try to get numbers assigned by IANA since that's supposed to be for services so common that many, many environments will use them (think SSH or FTP or TELNET).

Your network is your network and, if you want your servers on port 1234 (or even the TELNET or FTP ports for that matter), that's your business. Case in point, in our mainframe development area, port 23 is used for the 3270 terminal server which is a vastly different beast to telnet. If you want to telnet to the UNIX side of the mainframe, you use port 1023. That's sometimes annoying if you use telnet clients without specifying port 1023 since it hooks you up to a server that knows nothing of the telnet protocol - we have to break out of the telnet client and do it properly:

telnet 1023

If you really can't make the client side configurable, pick one in the second range, like 48042, and just use it, declaring that any other software on those boxes (including any added in the future) has to keep out of your way.

Code signing is required for product type Unit Test Bundle in SDK iOS 8.0

I fixed the issue (temporarily) by going to Edit Scheme, then in the Build section, removing my unit test target from being invoked in "Run".

Compare two Timestamp in java

There are after and before methods for Timestamp which will do the trick

How to pass variables from one php page to another without form?

use the get method in the url. If you want to pass over a variable called 'phone' as 0001112222:

<a href='whatever.php?phone=0001112222'>click</a>

then on the next page (whatever.php) you can access this var via:


The process cannot access the file because it is being used by another process (File is created but contains nothing)

You are writing to the file prior to closing your filestream:

using(FileStream fs=new FileStream(path,FileMode.OpenOrCreate))
using (StreamWriter str=new StreamWriter(fs))
   str.WriteLine(DateTime.Now.ToLongTimeString()+" "+DateTime.Now.ToLongDateString());
   string addtext="this line is added"+Environment.NewLine;



File.AppendAllText(path,addtext);  //Exception occurrs ??????????
string readtext=File.ReadAllText(path);

The above code should work, using the methods you are currently using. You should also look into the using statement and wrap your streams in a using block.

Calculating Page Load Time In JavaScript

Why so complicated? When you can do:

var loadTime = window.performance.timing.domContentLoadedEventEnd- window.performance.timing.navigationStart;

If you need more times check out the window.performance object:


Will show you the timing object:

connectEnd                 Time when server connection is finished.
connectStart               Time just before server connection begins.
domComplete                Time just before document readiness completes.
domContentLoadedEventEnd   Time after DOMContentLoaded event completes.
domContentLoadedEventStart Time just before DOMContentLoaded starts.
domInteractive             Time just before readiness set to interactive.
domLoading                 Time just before readiness set to loading.
domainLookupEnd            Time after domain name lookup.
domainLookupStart          Time just before domain name lookup.
fetchStart                 Time when the resource starts being fetched.
loadEventEnd               Time when the load event is complete.
loadEventStart             Time just before the load event is fired.
navigationStart            Time after the previous document begins unload.
redirectCount              Number of redirects since the last non-redirect.
redirectEnd                Time after last redirect response ends.
redirectStart              Time of fetch that initiated a redirect.
requestStart               Time just before a server request.
responseEnd                Time after the end of a response or connection.
responseStart              Time just before the start of a response.
timing                     Reference to a performance timing object.
navigation                 Reference to performance navigation object.
performance                Reference to performance object for a window.
type                       Type of the last non-redirect navigation event.
unloadEventEnd             Time after the previous document is unloaded.
unloadEventStart           Time just before the unload event is fired.

Browser Support

More Info

What does it mean when MySQL is in the state "Sending data"?

This is quite a misleading status. It should be called "reading and filtering data".

This means that MySQL has some data stored on the disk (or in memory) which is yet to be read and sent over. It may be the table itself, an index, a temporary table, a sorted output etc.

If you have a 1M records table (without an index) of which you need only one record, MySQL will still output the status as "sending data" while scanning the table, despite the fact it has not sent anything yet.

What is SOA "in plain english"?

Let's assume you have four cooks. In SOA, you assume they hate each other, so you strive to let them have to talk to each other as little as possible.

How do you do that? Well, you will first define the roles and interface -- cook 1 will make salad, cook 2 will make soup, cook 3 will make the steak, etc.. Then you will place the dishes well organised on the table (so these are the interfaces) and say, "Everybody please place your creation into your assigned dishes. Don't care about anybody else.".

This way, the four cooks have to talk to each other as little as possible, which is very good in software development -- not necessarily because they hate each other, but for other reasons like physical location, efficiency in making decisions etc.

It also means you can recombine the dishes (services) as you like. For example, you might just use the dessert to service a cafe, or just take the soup and combine it with a bread you bought from another company to provide a cheaper menu, or let other restaurants use your salads to combine with their dishes, etc.

One of the most successful implementation of SOA was at Amazon. Because of their design, they could re-package their whole infrastructure and sell it as Amazon Web Service.

*This is only one aspect of SOA.

Distribution certificate / private key not installed

Add a new Production Certificate here, then download the .cer file and double click it to add it to Keychain.

All will be fine now, don't forget to restart Xcode!!!

How to list running screen sessions?

To list all of the screen sessions for a user, run the following command as that user:

screen -ls

To see all screen sessions on a specific machine you can do:

ls -laR /var/run/screen/

I get this on my machine:

gentle ~ # ls -laR /var/run/screen/

total 1
drwxrwxr-x  4 root utmp   96 Mar  1  2005 .
drwxr-xr-x 10 root root  840 Feb  1 03:10 ..
drwx------  2 josh users  88 Jan 13 11:33 S-josh
drwx------  2 root root   48 Feb 11 10:50 S-root

total 0
drwx------ 2 josh users 88 Jan 13 11:33 .
drwxrwxr-x 4 root utmp  96 Mar  1  2005 ..
prwx------ 1 josh users  0 Feb 11 10:41 12931.pts-0.gentle

total 0
drwx------ 2 root root 48 Feb 11 10:50 .
drwxrwxr-x 4 root utmp 96 Mar  1  2005 ..

This is a rather brilliantly Unixy use of Unix Sockets wrapped in filesystem permissions to handle security, state, and streams.

How to call a JavaScript function, declared in <head>, in the body when I want to call it

I'm not sure what you mean by "myself".

Any JavaScript function can be called by an event, but you must have some sort of event to trigger it.

e.g. On page load:

<body onload="myfunction();">

Or on mouseover:

<table onmouseover="myfunction();">

As a result the first question is, "What do you want to do to cause the function to execute?"

After you determine that it will be much easier to give you a direct answer.

convert month from name to number

$string = "July";
echo $month_number = date("n",strtotime($string));

returns '7' [month number]

Use date("m",strtotime($string)); for the output "08"

For more formats reffer this..

CodeIgniter: How to use WHERE clause and OR clause

$where = "name='Joe' AND status='boss' OR status='active'";


Though I am 3/4 of a month late, you still execute the following after your where clauses are defined... $this->db->get("tbl_name");

How to verify static void method has been called with power mockito

If you are mocking the behavior (with something like doNothing()) there should really be no need to call to verify*(). That said, here's my stab at re-writing your test method:

public class InternalServiceTest { //Note the renaming of the test class.
   public void testProcessOrder() {
        InternalService is = new InternalService();
        Order order = mock(Order.class);

        //Mock Behavior
        doNothing().when(InternalUtils.class); //This is the preferred way
                                               //to mock static void methods.
        InternalUtils.sendEmail(anyString(), anyString(), anyString(), anyString());


        verifyStatic(InternalUtils.class); //Similar to how you mock static methods
                                           //this is how you verify them.
        InternalUtils.sendEmail(anyString(), anyString(), anyString(), anyString());

I grouped into four sections to better highlight what is going on:

1. Variables

I choose to declare any instance variables / method arguments / mock collaborators here. If it is something used in multiple tests, consider making it an instance variable of the test class.

2. Mock Behavior

This is where you define the behavior of all of your mocks. You're setting up return values and expectations here, prior to executing the code under test. Generally speaking, if you set the mock behavior here you wouldn't need to verify the behavior later.

3. Execute

Nothing fancy here; this just kicks off the code being tested. I like to give it its own section to call attention to it.

4. Verify

This is when you call any method starting with verify or assert. After the test is over, you check that the things you wanted to have happen actually did happen. That is the biggest mistake I see with your test method; you attempted to verify the method call before it was ever given a chance to run. Second to that is you never specified which static method you wanted to verify.

Additional Notes

This is mostly personal preference on my part. There is a certain order you need to do things in but within each grouping there is a little wiggle room. This helps me quickly separate out what is happening where.

I also highly recommend going through the examples at the following sites as they are very robust and can help with the majority of the cases you'll need:

Serialize and Deserialize Json and Json Array in Unity

Unity added JsonUtility to their API after 5.3.3 Update. Forget about all the 3rd party libraries unless you are doing something more complicated. JsonUtility is faster than other Json libraries. Update to Unity 5.3.3 version or above then try the solution below.

JsonUtility is a lightweight API. Only simple types are supported. It does not support collections such as Dictionary. One exception is List. It supports List and List array!

If you need to serialize a Dictionary or do something other than simply serializing and deserializing simple datatypes, use a third-party API. Otherwise, continue reading.

Example class to serialize:

public class Player
    public string playerId;
    public string playerLoc;
    public string playerNick;


Serializing Part A:

Serialize to Json with the public static string ToJson(object obj); method.

Player playerInstance = new Player();
playerInstance.playerId = "8484239823";
playerInstance.playerLoc = "Powai";
playerInstance.playerNick = "Random Nick";

//Convert to JSON
string playerToJson = JsonUtility.ToJson(playerInstance);


{"playerId":"8484239823","playerLoc":"Powai","playerNick":"Random Nick"}

Serializing Part B:

Serialize to Json with the public static string ToJson(object obj, bool prettyPrint); method overload. Simply passing true to the JsonUtility.ToJson function will format the data. Compare the output below to the output above.

Player playerInstance = new Player();
playerInstance.playerId = "8484239823";
playerInstance.playerLoc = "Powai";
playerInstance.playerNick = "Random Nick";

//Convert to JSON
string playerToJson = JsonUtility.ToJson(playerInstance, true);


    "playerId": "8484239823",
    "playerLoc": "Powai",
    "playerNick": "Random Nick"

Deserializing Part A:

Deserialize json with the public static T FromJson(string json); method overload.

string jsonString = "{\"playerId\":\"8484239823\",\"playerLoc\":\"Powai\",\"playerNick\":\"Random Nick\"}";
Player player = JsonUtility.FromJson<Player>(jsonString);

Deserializing Part B:

Deserialize json with the public static object FromJson(string json, Type type); method overload.

string jsonString = "{\"playerId\":\"8484239823\",\"playerLoc\":\"Powai\",\"playerNick\":\"Random Nick\"}";
Player player = (Player)JsonUtility.FromJson(jsonString, typeof(Player));

Deserializing Part C:

Deserialize json with the public static void FromJsonOverwrite(string json, object objectToOverwrite); method. When JsonUtility.FromJsonOverwrite is used, no new instance of that Object you are deserializing to will be created. It will simply re-use the instance you pass in and overwrite its values.

This is efficient and should be used if possible.

Player playerInstance;
void Start()
    //Must create instance once
    playerInstance = new Player();

void deserialize()
    string jsonString = "{\"playerId\":\"8484239823\",\"playerLoc\":\"Powai\",\"playerNick\":\"Random Nick\"}";

    //Overwrite the values in the existing class instance "playerInstance". Less memory Allocation
    JsonUtility.FromJsonOverwrite(jsonString, playerInstance);


Your Json contains multiple data objects. For example playerId appeared more than once. Unity's JsonUtility does not support array as it is still new but you can use a helper class from this person to get array working with JsonUtility.

Create a class called JsonHelper. Copy the JsonHelper directly from below.

public static class JsonHelper
    public static T[] FromJson<T>(string json)
        Wrapper<T> wrapper = JsonUtility.FromJson<Wrapper<T>>(json);
        return wrapper.Items;

    public static string ToJson<T>(T[] array)
        Wrapper<T> wrapper = new Wrapper<T>();
        wrapper.Items = array;
        return JsonUtility.ToJson(wrapper);

    public static string ToJson<T>(T[] array, bool prettyPrint)
        Wrapper<T> wrapper = new Wrapper<T>();
        wrapper.Items = array;
        return JsonUtility.ToJson(wrapper, prettyPrint);

    private class Wrapper<T>
        public T[] Items;

Serializing Json Array:

Player[] playerInstance = new Player[2];

playerInstance[0] = new Player();
playerInstance[0].playerId = "8484239823";
playerInstance[0].playerLoc = "Powai";
playerInstance[0].playerNick = "Random Nick";

playerInstance[1] = new Player();
playerInstance[1].playerId = "512343283";
playerInstance[1].playerLoc = "User2";
playerInstance[1].playerNick = "Rand Nick 2";

//Convert to JSON
string playerToJson = JsonHelper.ToJson(playerInstance, true);


    "Items": [
            "playerId": "8484239823",
            "playerLoc": "Powai",
            "playerNick": "Random Nick"
            "playerId": "512343283",
            "playerLoc": "User2",
            "playerNick": "Rand Nick 2"

Deserializing Json Array:

string jsonString = "{\r\n    \"Items\": [\r\n        {\r\n            \"playerId\": \"8484239823\",\r\n            \"playerLoc\": \"Powai\",\r\n            \"playerNick\": \"Random Nick\"\r\n        },\r\n        {\r\n            \"playerId\": \"512343283\",\r\n            \"playerLoc\": \"User2\",\r\n            \"playerNick\": \"Rand Nick 2\"\r\n        }\r\n    ]\r\n}";

Player[] player = JsonHelper.FromJson<Player>(jsonString);




If this is a Json array from the server and you did not create it by hand:

You may have to Add {"Items": in front of the received string then add } at the end of it.

I made a simple function for this:

string fixJson(string value)
    value = "{\"Items\":" + value + "}";
    return value;

then you can use it:

string jsonString = fixJson(yourJsonFromServer);
Player[] player = JsonHelper.FromJson<Player>(jsonString);

3.Deserialize json string without class && De-serializing Json with numeric properties

This is a Json that starts with a number or numeric properties.

For example:

"USD" : {"15m" : 1740.01, "last" : 1740.01, "buy" : 1740.01, "sell" : 1744.74, "symbol" : "$"}, 

"ISK" : {"15m" : 179479.11, "last" : 179479.11, "buy" : 179479.11, "sell" : 179967, "symbol" : "kr"},

"NZD" : {"15m" : 2522.84, "last" : 2522.84, "buy" : 2522.84, "sell" : 2529.69, "symbol" : "$"}

Unity's JsonUtility does not support this because the "15m" property starts with a number. A class variable cannot start with an integer.

Download SimpleJSON.cs from Unity's wiki.

To get the "15m" property of USD:

var N = JSON.Parse(yourJsonString);
string price = N["USD"]["15m"].Value;

To get the "15m" property of ISK:

var N = JSON.Parse(yourJsonString);
string price = N["ISK"]["15m"].Value;

To get the "15m" property of NZD:

var N = JSON.Parse(yourJsonString);
string price = N["NZD"]["15m"].Value;

The rest of the Json properties that doesn't start with a numeric digit can be handled by Unity's JsonUtility.


Problems when serializing with JsonUtility.ToJson?

Getting empty string or "{}" with JsonUtility.ToJson?

A. Make sure that the class is not an array. If it is, use the helper class above with JsonHelper.ToJson instead of JsonUtility.ToJson.

B. Add [Serializable] to the top of the class you are serializing.

C. Remove property from the class. For example, in the variable, public string playerId { get; set; } remove { get; set; }. Unity cannot serialize this.

Problems when deserializing with JsonUtility.FromJson?

A. If you get Null, make sure that the Json is not a Json array. If it is, use the helper class above with JsonHelper.FromJson instead of JsonUtility.FromJson.

B. If you get NullReferenceException while deserializing, add [Serializable] to the top of the class.

C.Any other problems, verify that your json is valid. Go to this site here and paste the json. It should show you if the json is valid. It should also generate the proper class with the Json. Just make sure to remove remove { get; set; } from each variable and also add [Serializable] to the top of each class generated.


If for some reason Newtonsoft.Json must be used then check out the forked version for Unity here. Note that you may experience crash if certain feature is used. Be careful.

To answer your question:

Your original data is


Add {"Items": in front of it then add } at the end of it.

Code to do this:

serviceData = "{\"Items\":" + serviceData + "}";

Now you have:


To serialize the multiple data from php as arrays, you can now do

public player[] playerInstance;
playerInstance = JsonHelper.FromJson<player>(serviceData);

playerInstance[0] is your first data

playerInstance[1] is your second data

playerInstance[2] is your third data

or data inside the class with playerInstance[0].playerLoc, playerInstance[1].playerLoc, playerInstance[2].playerLoc ......

You can use playerInstance.Length to check the length before accessing it.

NOTE: Remove { get; set; } from the player class. If you have { get; set; }, it won't work. Unity's JsonUtility does NOT work with class members that are defined as properties.

JS: iterating over result of getElementsByClassName using Array.forEach

Here is a test I created on jsperf:

The most perfomant version in Chrome and Firefox is the good old for loop in combination with document.getElementsByClassName:

var elements = document.getElementsByClassName('testClass'), elLength = elements.length;
for (var i = 0; i < elLength; i++) {
    elements.item(i).textContent = 'Tested';

In Safari this variant is the winner:

var elements = document.querySelectorAll('.testClass');
elements.forEach((element) => {
    element.textContent = 'Tested';

If you want the most perfomant variant for all browsers it might be this one:

var elements = document.getElementsByClassName('testClass');
    (element) => {
        return element.textContent = 'Tested';

Any way to replace characters on Swift String?

you can test this:

let newString = test.stringByReplacingOccurrencesOfString(" ", withString: "+", options: nil, range: nil)

How to delete empty folders using windows command prompt?

This can be easily done by using rd command with two parameters:

rd <folder> /Q /S
  • /Q - Quiet mode, do not ask if ok to remove a directory tree with /S

  • /S - Removes all directories and files in the specified directory in addition to the directory itself. Used to remove a directory tree.

SQL Server 2008 Connection Error "No process is on the other end of the pipe"

My resolution was to login using the Windows Login then go to security>Logins locate the troubled ID And retype the used password. The restart the services...

How do I call a non-static method from a static method in C#?

You'll need to create an instance of the class and invoke the method on it.

public class Foo
    public void Data1()

    public static void Data2()
         Foo foo = new Foo();

how to get current location in google map android

This Code in MapsActivity Class works for me :

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

private GoogleMap mMap;
LocationManager locationManager;
LocationListener locationListener;

public void centreMapOnLocation(Location location, String title){

    LatLng userLocation = new LatLng(location.getLatitude(),location.getLongitude());
    mMap.addMarker(new MarkerOptions().position(userLocation).title(title));


public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);

    if (grantResults.length>0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){

        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED){

            Location lastKnownLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            centreMapOnLocation(lastKnownLocation,"Your Location");

protected void onCreate(Bundle savedInstanceState) {
    // Obtain the SupportMapFragment and get notified when the map is ready to be used.
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()

public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;

    Intent intent = getIntent();
    if (intent.getIntExtra("Place Number",0) == 0 ){

        // Zoom into users location
        locationManager = (LocationManager)this.getSystemService(Context.LOCATION_SERVICE);
        locationListener = new LocationListener() {
            public void onLocationChanged(Location location) {
                centreMapOnLocation(location,"Your Location");

            public void onStatusChanged(String s, int i, Bundle bundle) {


            public void onProviderEnabled(String s) {


            public void onProviderDisabled(String s) {


        if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED){
                Location lastKnownLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
                centreMapOnLocation(lastKnownLocation,"Your Location");
        } else {

            ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.ACCESS_FINE_LOCATION},1);



Matlab: Running an m-file from command-line

Here is what I would use instead, to gracefully handle errors from the script:

"C:\<a long path here>\matlab.exe" -nodisplay -nosplash -nodesktop -r "try, run('C:\<a long path here>\mfile.m'), catch, exit, end, exit"

If you want more verbosity:

"C:\<a long path here>\matlab.exe" -nodisplay -nosplash -nodesktop -r "try, run('C:\<a long path here>\mfile.m'), catch me, fprintf('%s / %s\n',me.identifier,me.message), end, exit"

I found the original reference here. Since original link is now gone, here is the link to an alternate newreader still alive today:

To switch from vertical split to horizontal split fast in Vim

Following Mark Rushakoff's tip above, here is my mapping:

" vertical to horizontal ( | -> -- )
noremap <c-w>-  <c-w>t<c-w>K
" horizontal to vertical ( -- -> | )
noremap <c-w>\|  <c-w>t<c-w>H
noremap <c-w>\  <c-w>t<c-w>H
noremap <c-w>/  <c-w>t<c-w>H

Edit: use Ctrl-w r to swap two windows if they are not in the good order.

CSS: 100% width or height while keeping aspect ratio?

I think this is what your looking for, i was looking for it my self, but then i remembered it again befor i found the code.

background-repeat: repeat-x;
background-position: top;
background-attachment: fixed;

digital evolution is on its way.

Show "Open File" Dialog

Addition to what Albert has already said:

This code (a mashup of various samples) provides the ability to have a SaveAs dialog box

Function getFileName() As String
    Dim fDialog    As Object
    Set fDialog = Application.FileDialog(msoFileDialogSaveAs)
    Dim varFile As Variant

    With fDialog
       .AllowMultiSelect = False
       .Title = "Select File Location to Export XLSx :"
       .InitialFileName = "jeffatwood.xlsx"

    If .Show = True Then
       For Each varFile In .SelectedItems
         getFileName = varFile
    End If
End With
End Function

Generating random whole numbers in JavaScript in a specific range?

The other answers don't account for the perfectly reasonable parameters of 0 and 1. Instead you should use the round instead of ceil or floor:

function randomNumber(minimum, maximum){
    return Math.round( Math.random() * (maximum - minimum) + minimum);

console.log(randomNumber(0,1));  # 0 1 1 0 1 0
console.log(randomNumber(5,6));  # 5 6 6 5 5 6
console.log(randomNumber(3,-1)); # 1 3 1 -1 -1 -1

How do I delete NuGet packages that are not referenced by any project in my solution?

From the Package Manager console window, often whatever command you used to install a package can be used to uninstall that package. Simply replace the INSTALL command with UNINSTALL.

For example, to install PowerTCPTelnet, the command is:

Install-Package PowerTCPTelnet -Version 4.4.9

To uninstall same, the command is:

Uninstall-Package PowerTCPTelnet -Version 4.4.9

Keyboard shortcut to "untab" (move a block of code to the left) in eclipse / aptana?

Shift-tab does that in Flex Builder (Based on Eclipse) - SO it hopefully should work in regular eclipse :)

Converting SVG to PNG using C#

To add to the response from @Anish, if you are having issues with not seeing the text when exporting the SVG to an image, you can create a recursive function to loop through the children of the SVGDocument, try to cast it to a SvgText if possible (add your own error checking) and set the font family and style.

    foreach(var child in svgDocument.Children)

    public void SetFont(SvgElement element)
        foreach(var child in element.Children)
            SetFont(child); //Call this function again with the child, this will loop
                            //until the element has no more children

            var svgText = (SvgText)parent; //try to cast the element as a SvgText
                                           //if it succeeds you can modify the font

            svgText.Font = new Font("Arial", 12.0f);
            svgText.FontSize = new SvgUnit(12.0f);


Let me know if there are questions.

Android Studio: /dev/kvm device permission denied

What finally fixed it for me on Ubuntu 18.04 was:

sudo apt install qemu-kvm
sudo adduser $USER kvm
sudo chown $USER /dev/kvm

How do I check if a variable exists?

A way that often works well for handling this kind of situation is to not explicitly check if the variable exists but just go ahead and wrap the first usage of the possibly non-existing variable in a try/except NameError:

# Search for entry.
for x in y:
  if x == 3:
    found = x

# Work with found entry.
  print('Found: {0}'.format(found))
except NameError:
  print('Not found')
  # Handle rest of Found case here

Request UAC elevation from within a Python script?

It took me a little while to get dguaraglia's answer working, so in the interest of saving others time, here's what I did to implement this idea:

import os
import sys
import as shell
ASADMIN = 'asadmin'

if sys.argv[-1] != ASADMIN:
    script = os.path.abspath(sys.argv[0])
    params = ' '.join([script] + sys.argv[1:] + [ASADMIN])
    shell.ShellExecuteEx(lpVerb='runas', lpFile=sys.executable, lpParameters=params)

Using both Python 2.x and Python 3.x in IPython Notebook

Following are the steps to add the python2 kernel to jupyter notebook::

open a terminal and create a new python 2 environment: conda create -n py27 python=2.7

activate the environment: Linux source activate py27 or windows activate py27

install the kernel in the env: conda install notebook ipykernel

install the kernel for outside the env: ipython kernel install --user

close the env: source deactivate

Although a late answer hope someone finds it useful :p

Checking if a double (or float) is NaN in C++

inline bool IsNan(float f)
    const uint32 u = *(uint32*)&f;
    return (u&0x7F800000) == 0x7F800000 && (u&0x7FFFFF);    // Both NaN and qNan.

inline bool IsNan(double d)
    const uint64 u = *(uint64*)&d;
    return (u&0x7FF0000000000000ULL) == 0x7FF0000000000000ULL && (u&0xFFFFFFFFFFFFFULL);

This works if sizeof(int) is 4 and sizeof(long long) is 8.

During run time it is only comparison, castings do not take any time. It just changes comparison flags configuration to check equality.

What is the best way to give a C# auto-property an initial value?

Have you tried using the DefaultValueAttribute or ShouldSerialize and Reset methods in conjunction with the constructor? I feel like one of these two methods is necessary if you're making a class that might show up on the designer surface or in a property grid.

SQL Error: ORA-01861: literal does not match format string 01861

If you provide proper date format it should work please recheck once if you have given correct date format in insert values

Assign variable in if condition statement, good practice or not?

If you were to refer to Martin Fowlers book Refactoring improving the design of existing code ! Then there are several cases where it would be good practice eg. long complex conditionals to use a function or method call to assert your case:


One of the most common areas of complexity in a program lies in complex conditional logic. As you write code to test conditions and to do various things depending on various conditions, you quickly end up with a pretty long method. Length of a method is in itself a factor that makes it harder to read, but conditions increase the difficulty. The problem usually lies in the fact that the code, both in the condition checks and in the actions, tells you what happens but can easily obscure why it happens.

As with any large block of code, you can make your intention clearer by decomposing it and replacing chunks of code with a method call named after the intention of that block of code. > With conditions you can receive further benefit by doing this for the conditional part and each of the alternatives. This way you highlight the condition and make it clearly what you > are branching on. You also highlight the reason for the branching."

And yes his answer is also valid for Java implementations. It does not assign the conditional function to a variable though in the examples.

CSS text-decoration underline color

(for fellow googlers, copied from duplicate question) This answer is outdated since text-decoration-color is now supported by most modern browsers.

You can do this via the following CSS rule as an example:


If this rule isn't supported by an older browser, you can use the following solution:

Setting your word with a border-bottom:

a:link {
  color: red;
  text-decoration: none;
  border-bottom: 1px solid blue;
a:hover {
 border-bottom-color: green;

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

Here is simple function, tested in bash. 1st param of function is string, 2nd param is number of characters to be stripped

function stringStripNCharsFromStart { echo ${1:$2:${#1}} }

Usage: enter image description here

Convert char to int in C and C++

It sort of depends on what you mean by "convert".

If you have a series of characters that represents an integer, like "123456", then there are two typical ways to do that in C: Use a special-purpose conversion like atoi() or strtol(), or the general-purpose sscanf(). C++ (which is really a different language masquerading as an upgrade) adds a third, stringstreams.

If you mean you want the exact bit pattern in one of your int variables to be treated as a char, that's easier. In C the different integer types are really more of a state of mind than actual separate "types". Just start using it where chars are asked for, and you should be OK. You might need an explicit conversion to make the compiler quit whining on occasion, but all that should do is drop any extra bits past 256.

Find an element by class name, from a known parent element

You were close. You can do:

var element = $("#parentDiv").find(".myClassNameOfInterest");

Alternatively, you can do:

var element = $(".myClassNameOfInterest", "#parentDiv");

...which sets the context of the jQuery object to the #parentDiv.


Additionally, it may be faster in some browsers if you do div.myClassNameOfInterest instead of just .myClassNameOfInterest.

What does <T> denote in C#

It is a Generic Type Parameter.

A generic type parameter allows you to specify an arbitrary type T to a method at compile-time, without specifying a concrete type in the method or class declaration.

For example:

public T[] Reverse<T>(T[] array)
    var result = new T[array.Length];
    int j=0;
    for(int i=array.Length - 1; i>= 0; i--)
        result[j] = array[i];
    return result;

reverses the elements in an array. The key point here is that the array elements can be of any type, and the function will still work. You specify the type in the method call; type safety is still guaranteed.

So, to reverse an array of strings:

string[] array = new string[] { "1", "2", "3", "4", "5" };
var result = reverse(array);

Will produce a string array in result of { "5", "4", "3", "2", "1" }

This has the same effect as if you had called an ordinary (non-generic) method that looks like this:

public string[] Reverse(string[] array)
    var result = new string[array.Length];
    int j=0;
    for(int i=array.Length - 1; i >= 0; i--)
        result[j] = array[i];
    return result;

The compiler sees that array contains strings, so it returns an array of strings. Type string is substituted for the T type parameter.

Generic type parameters can also be used to create generic classes. In the example you gave of a SampleCollection<T>, the T is a placeholder for an arbitrary type; it means that SampleCollection can represent a collection of objects, the type of which you specify when you create the collection.


var collection = new SampleCollection<string>();

creates a collection that can hold strings. The Reverse method illustrated above, in a somewhat different form, can be used to reverse the collection's members.

Change the background color of a row in a JTable

This is basically as simple as repainting the table. I haven't found a way to selectively repaint just one row/column/cell however.

In this example, clicking on the button changes the background color for a row and then calls repaint.

public class TableTest {
    public static void main(String[] args) {
        JFrame frame = new JFrame();

        final Color[] rowColors = new Color[] {
                randomColor(), randomColor(), randomColor()
        final JTable table = new JTable(3, 3);
        table.setDefaultRenderer(Object.class, new TableCellRenderer() {
            public Component getTableCellRendererComponent(JTable table,
                    Object value, boolean isSelected, boolean hasFocus,
                    int row, int column) {
                JPanel pane = new JPanel();
                return pane;
        frame.setLayout(new BorderLayout());

        JButton btn = new JButton("Change row2's color");
        btn.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                rowColors[1] = randomColor();

        frame.add(table, BorderLayout.NORTH);
        frame.add(btn, BorderLayout.SOUTH);

    private static Color randomColor() {
        Random rnd = new Random();
        return new Color(rnd.nextInt(256),
                rnd.nextInt(256), rnd.nextInt(256));

Disable autocomplete via CSS

If you're using a form you can disable all the autocompletes with,

<form id="Form1" runat="server" autocomplete="off">

How to tell Maven to disregard SSL errors (and trusting all certs)?

An alternative that worked for me is to tell Maven to use http: instead of https: when using Maven Central by adding the following to settings.xml:

        <name>Central without ssl</name>

Your mileage may vary of course.

PHP: Limit foreach() statement?

There are many ways, one is to use a counter:

$i = 0;
foreach ($arr as $k => $v) {
    /* Do stuff */
    if (++$i == 2) break;

Other way would be to slice the first 2 elements, this isn't as efficient though:

foreach (array_slice($arr, 0, 2) as $k => $v) {
    /* Do stuff */

You could also do something like this (basically the same as the first foreach, but with for):

for ($i = 0, reset($arr); list($k,$v) = each($arr) && $i < 2; $i++) {

How to get everything after last slash in a URL?

extracted_url = url[url.rfind("/")+1:];

Stripping everything but alphanumeric chars from a string in Python

You could try:

print ''.join(ch for ch in some_string if ch.isalnum())

Why number 9 in kill -9 command in unix?

I don't think there is any significance to number 9. In addition, despite common believe, kill is used not only to kill processes but also send a signal to a process. If you are really curious you can read here and here.

How to get duplicate items from a list using LINQ?

Hope this wil help

int[] listOfItems = new[] { 4, 2, 3, 1, 6, 4, 3 };

var duplicates = listOfItems 
    .GroupBy(i => i)
    .Where(g => g.Count() > 1)
    .Select(g => g.Key);

foreach (var d in duplicates)

PHP & localStorage;

localStorage is something that is kept on the client side. There is no data transmitted to the server side.

You can only get the data with JavaScript and you can send it to the server side with Ajax.

Java String split removed empty values

String[] split = data.split("\\|",-1);

This is not the actual requirement in all the time. The Drawback of above is show below:

Scenerio 1:
When all data are present:
    String data = "5|6|7||8|9|10|";
    String[] split = data.split("\\|");
    String[] splt = data.split("\\|",-1);
    System.out.println(split.length); //output: 7
    System.out.println(splt.length); //output: 8

When data is missing:

Scenerio 2: Data Missing
    String data = "5|6|7||8|||";
    String[] split = data.split("\\|");
    String[] splt = data.split("\\|",-1);
    System.out.println(split.length); //output: 5
    System.out.println(splt.length); //output: 8

Real requirement is length should be 7 although there is data missing. Because there are cases such as when I need to insert in database or something else. We can achieve this by using below approach.

    String data = "5|6|7||8|||";
    String[] split = data.split("\\|");
    String[] splt = data.replaceAll("\\|$","").split("\\|",-1);
    System.out.println(split.length); //output: 5
    System.out.println(splt.length); //output:7

What I've done here is, I'm removing "|" pipe at the end and then splitting the String. If you have "," as a seperator then you need to add ",$" inside replaceAll.

jquery stop child triggering parent event

The answers here took the OP's question too literally. How can these answers be expanded into a scenario where there are MANY child elements, not just a single <a> tag? Here's one way.

Let's say you have a photo gallery with a blacked out background and the photos centered in the browser. When you click the black background (but not anything inside of it) you want the overlay to close.

Here's some possible HTML:

<div class="gallery" style="background: black">
    <div class="contents"> <!-- Let's say this div is 50% wide and centered -->
        <h1>Awesome Photos</h1>
        <img src="img1.jpg"><br>
        <img src="img2.jpg"><br>
        <img src="img3.jpg"><br>
        <img src="img4.jpg"><br>
        <img src="img5.jpg">

And here's how the JavaScript would work:


$('.gallery > .contents').click(
    function(e) {

This will stop the click events from elements inside .contents from every research .gallery so the gallery will close only when you click in the faded black background area, but not when you click in the content area. This can be applied to many different scenarios.

Objective-C and Swift URL encoding

int strLength = 0;
NSString *urlStr = @"http://www";
NSLog(@" urlStr : %@", urlStr );
NSMutableString *mutableUrlStr = [urlStr mutableCopy];
NSLog(@" mutableUrlStr : %@", mutableUrlStr );
strLength = [mutableUrlStr length];
[mutableUrlStr replaceOccurrencesOfString:@":" withString:@"%3A" options:NSCaseInsensitiveSearch range:NSMakeRange(0, strLength)];
NSLog(@" mutableUrlStr : %@", mutableUrlStr );
strLength = [mutableUrlStr length];
[mutableUrlStr replaceOccurrencesOfString:@"/" withString:@"%2F" options:NSCaseInsensitiveSearch range:NSMakeRange(0, strLength)];
NSLog(@" mutableUrlStr : %@", mutableUrlStr );

Collection was modified; enumeration operation may not execute in ArrayList

I agree with several of the points I've read in this post and I've incorporated them into my solution to solve the exact same issue as the original posting.

That said, the comments I appreciated are:

  • "unless you are using .NET 1.0 or 1.1, use List<T> instead of ArrayList. "

  • "Also, add the item(s) to be deleted to a new list. Then go through and delete those items." .. in my case I just created a new List and the populated it with the valid data values.


private List<string> managedLocationIDList = new List<string>();
string managedLocationIDs = ";1321;1235;;" // user input, should be semicolon seperated list of values

managedLocationIDList.AddRange(managedLocationIDs.Split(new char[] { ';' }));
List<string> checkLocationIDs = new List<string>();

// Remove any duplicate ID's and cleanup the string holding the list if ID's
Functions helper = new Functions();
checkLocationIDs = helper.ParseList(managedLocationIDList);

public List<string> ParseList(List<string> checkList)
    List<string> verifiedList = new List<string>();

    foreach (string listItem in checkList)
    if (!verifiedList.Contains(listItem.Trim()) && listItem != string.Empty)

    return verifiedList;

Accessing the last entry in a Map

Find missing all elements from array
        int[] array = {3,5,7,8,2,1,32,5,7,9,30,5};
        TreeMap<Integer, Integer> map = new TreeMap<>();
        for(int i=0;i<array.length;i++) {
            map.put(array[i], 1);
        int maxSize = map.lastKey();
        for(int j=0;j<maxSize;j++) {
            if(null == map.get(j))
                System.out.println("Missing `enter code here`No:"+j);

Calculate mean and standard deviation from a vector of samples in C++ using Boost

2x faster than the versions before mentioned - mostly because transform() and inner_product() loops are joined. Sorry about my shortcut/typedefs/macro: Flo = float. CR const ref. VFlo - vector. Tested in VS2010

#define fe(EL, CONTAINER)   for each (auto EL in CONTAINER)  //VS2010
Flo stdDev(VFlo CR crVec) {
    SZ  n = crVec.size();               if (n < 2) return 0.0f;
    Flo fSqSum = 0.0f, fSum = 0.0f;
    fe(f, crVec) fSqSum += f * f;       // EDIT: was Cit(VFlo, crVec) {
    fe(f, crVec) fSum   += f;
    Flo fSumSq      = fSum * fSum;
    Flo fSumSqDivN  = fSumSq / n;
    Flo fSubSqSum   = fSqSum - fSumSqDivN;
    Flo fPreSqrt    = fSubSqSum / (n - 1);
    return sqrt(fPreSqrt);

What is Ruby's double-colon `::`?

:: is basically a namespace resolution operator. It allows you to access items in modules, or class-level items in classes. For example, say you had this setup:

module SomeModule
    module InnerModule
        class MyClass
            CONSTANT = 4

You could access CONSTANT from outside the module as SomeModule::InnerModule::MyClass::CONSTANT.

It doesn't affect instance methods defined on a class, since you access those with a different syntax (the dot .).

Relevant note: If you want to go back to the top-level namespace, do this: ::SomeModule – Benjamin Oakes

Exit from app when click button in android phonegap?

}else if(navigator.device){

How do I change the font size of a UILabel in Swift?

You can do it like this:

label.font = UIFont(name: label.font.fontName, size: 20)

Or like this:

label.font = label.font.withSize(20)

This will use the same font. 20 can be whatever size you want of course.

Note: The latter option will overwrite the current font weight to regular so if you want to preserve the font weight use the first option.

Swift 3 Update:

label.font = label.font.withSize(20)

Swift 4 Update:

label.font = label.font.withSize(20)


label.font = UIFont(name:"fontname", size: 20.0)

and if you use the system fonts

label.font = UIFont.systemFont(ofSize: 20.0)
label.font = UIFont.boldSystemFont(ofSize: 20.0)
label.font = UIFont.italicSystemFont(ofSize: 20.0)

Remove the first character of a string

python 2.x

s = ":dfa:sif:e"
print s[1:]

python 3.x

s = ":dfa:sif:e"

both prints


Remove All Event Listeners of Specific Type

That is not possible without intercepting addEventListener calls and keep track of the listeners or use a library that allows such features unfortunately. It would have been if the listeners collection was accessible but the feature wasn't implemented.

The closest thing you can do is to remove all listeners by cloning the element, which will not clone the listeners collection.

Note: This will also remove listeners on element's children.

var el = document.getElementById('el-id'),
    elClone = el.cloneNode(true);

el.parentNode.replaceChild(elClone, el);

How to check if an alert exists using WebDriver?

This code will check whether the alert is present or not.

public static void isAlertPresent(){
    Alert alert = driver.switchTo().alert();
    System.out.println(alert.getText()+" Alert is Displayed"); 
    catch(NoAlertPresentException ex){
    System.out.println("Alert is NOT Displayed");

html select option SELECTED

Just use the array of options, to see, which option is currently selected.

$options = array( 'one', 'two', 'three' );

$output = '';
for( $i=0; $i<count($options); $i++ ) {
  $output .= '<option ' 
             . ( $_GET['sel'] == $options[$i] ? 'selected="selected"' : '' ) . '>' 
             . $options[$i] 
             . '</option>';

Sidenote: I would define a value to be some kind of id for each element, else you may run into problems, when two options have the same string representation.

How to convert byte[] to InputStream?

Should be easy to find in the javadocs...

byte[] byteArr = new byte[] { 0xC, 0xA, 0xF, 0xE };
InputStream is = new ByteArrayInputStream(byteArr);

How to set top position using jquery

You can use CSS to do the trick:

$("#yourElement").css({ top: '100px' });

How can I deserialize JSON to a simple Dictionary<string,string> in ASP.NET?

My approach directly deserializes to IDictionary, without JObject or ExpandObject in between. The code uses converter, which is basically copied from ExpandoObjectConverter class found in JSON.NET sourcecode, but using IDictionary instead of ExpandoObject.


var settings = new JsonSerializerSettings()
    Converters = { new DictionaryConverter() },
var result = JsonConvert.DeserializeObject<IDictionary<string, object>>(json, settings);


// based on ExpandoObjectConverter, but using arrays instead of IList, to behave similar to System.Web.Script.Serialization.JavaScriptSerializer
public class DictionaryConverter : JsonConverter
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        return ReadValue(reader);

    public override bool CanConvert(Type objectType)
        return (objectType == typeof(IDictionary<string, object>));

    public override bool CanWrite
        get { return false; }

    private object ReadValue(JsonReader reader)
        while (reader.TokenType == JsonToken.Comment)
            if (!reader.Read())
                throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");

        switch (reader.TokenType)
            case JsonToken.StartObject:
                return ReadObject(reader);
            case JsonToken.StartArray:
                return ReadList(reader);
                if (IsPrimitiveToken(reader.TokenType))
                    return reader.Value;

                throw JsonSerializationExceptionCreate(reader, string.Format(CultureInfo.InvariantCulture, "Unexpected token when converting IDictionary<string, object>: {0}", reader.TokenType));

    private object ReadList(JsonReader reader)
        List<object> list = new List<object>();

        while (reader.Read())
            switch (reader.TokenType)
                case JsonToken.Comment:
                    object v = ReadValue(reader);

                case JsonToken.EndArray:
                    return list;

        throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");

    private object ReadObject(JsonReader reader)
        IDictionary<string, object> dictionary = new Dictionary<string, object>();
        while (reader.Read())
            switch (reader.TokenType)
                case JsonToken.PropertyName:
                    string propertyName = reader.Value.ToString();

                    if (!reader.Read())
                        throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");

                    object v = ReadValue(reader);

                    dictionary[propertyName] = v;
                case JsonToken.Comment:
                case JsonToken.EndObject:
                    return dictionary;

        throw JsonSerializationExceptionCreate(reader, "Unexpected end when reading IDictionary<string, object>.");

    //based on internal Newtonsoft.Json.JsonReader.IsPrimitiveToken
    internal static bool IsPrimitiveToken(JsonToken token)
        switch (token)
            case JsonToken.Integer:
            case JsonToken.Float:
            case JsonToken.String:
            case JsonToken.Boolean:
            case JsonToken.Undefined:
            case JsonToken.Null:
            case JsonToken.Date:
            case JsonToken.Bytes:
                return true;
                return false;

    // based on internal Newtonsoft.Json.JsonSerializationException.Create
    private static JsonSerializationException JsonSerializationExceptionCreate(JsonReader reader, string message, Exception ex = null)
        return JsonSerializationExceptionCreate(reader as IJsonLineInfo, reader.Path, message, ex);

    // based on internal Newtonsoft.Json.JsonSerializationException.Create
    private static JsonSerializationException JsonSerializationExceptionCreate(IJsonLineInfo lineInfo, string path, string message, Exception ex)
        message = JsonPositionFormatMessage(lineInfo, path, message);

        return new JsonSerializationException(message, ex);

    // based on internal Newtonsoft.Json.JsonPosition.FormatMessage
    internal static string JsonPositionFormatMessage(IJsonLineInfo lineInfo, string path, string message)
        if (!message.EndsWith(Environment.NewLine))
            message = message.Trim();

            if (!message.EndsWith(".", StringComparison.Ordinal))
                message += ".";

            message += " ";

        message += string.Format(CultureInfo.InvariantCulture, "Path '{0}'", path);

        if (lineInfo != null && lineInfo.HasLineInfo())
            message += string.Format(CultureInfo.InvariantCulture, ", line {0}, position {1}", lineInfo.LineNumber, lineInfo.LinePosition);

        message += ".";

        return message;

Tree view of a directory/folder in Windows?

If it is just viewing in tree view,One workaround is to use the Explorer in Notepad++ or any other tools.

SQL Network Interfaces, error: 50 - Local Database Runtime error occurred. Cannot create an automatic instance

I have solved above problem Applying below steps

enter image description here

And after you made thses changes, do following changes in your web.config

 <add name="DefaultConnection" connectionString="Data Source=(LocalDb)\v12.0;AttachDbFilename=|DataDirectory|\aspnet-Real-Time-Commenting-20170927122714.mdf;Initial Catalog=aspnet-Real-Time-Commenting-20170927122714;Integrated Security=true" providerName="System.Data.SqlClient" />

How to cancel/abort jQuery AJAX request?

Why should you abort the request?

If each request takes more than five seconds, what will happen?

You shouldn't abort the request if the parameter passing with the request is not changing. eg:- the request is for retrieving the notification data. In such situations, The nice approach is that set a new request only after completing the previous Ajax request.


    var fn = function(){

            url: 'ajax/progress.ftl',
            success: function(data) {
                //do something

            complete: function(){setTimeout(fn, 500);}

     var interval = setTimeout(fn, 500);


Socket File "/var/pgsql_socket/.s.PGSQL.5432" Missing In Mountain Lion (OS X Server)

File permissions are restrictive on the Postgres db owned by the Mac OS. These permissions are reset after reboot, or restart of Postgres: e.g. serveradmin start postgres.

So, temporarily reset the permissions or ownership:

sudo chmod o+rwx /var/pgsql_socket/.s.PGSQL.5432
sudo chown "webUser"  /var/pgsql_socket/.s.PGSQL.5432

Permissions resetting is not secure, so install a version of the db that you own for a solution.

What is an HttpHandler in ASP.NET

An HttpHandler (or IHttpHandler) is basically anything that is responsible for serving content. An ASP.NET page (aspx) is a type of handler.

You might write your own, for example, to serve images etc from a database rather than from the web-server itself, or to write a simple POX service (rather than SOAP/WCF/etc)

Using .text() to retrieve only text not nested in child tags

I liked this reusable implementation based on the clone() method found here to get only the text inside the parent element.

Code provided for easy reference:

    .clone()    //clone the element
    .children() //select all the children
    .remove()   //remove all the children
    .end()  //again go back to selected element

"Parse Error : There is a problem parsing the package" while installing Android application

I had this problem, even when I specified the correct minSDK and targetSDK version. My problem was, I was using "android:theme="@android:style/Theme.NoTitleBar.Fullscreen" in launcher activity, on Jellybean device. When I removed this attribute, it worked.

WARNING: Exception encountered during context initialization - cancelling refresh attempt

  1. To closed ideas,
  2. To remove all folder and file C:/Users/UserName/.m2/org/*,
  3. Open ideas and update Maven project,(right click on project -> maven->update maven project)
  4. After that update the project.

How to use foreach with a hash reference?

So, with Perl 5.20, the new answer is:

foreach my $key (keys $ad_grp_ref->%*) {

(which has the advantage of transparently working with more complicated expressions:

foreach my $key (keys $ad_grp_obj[3]->get_ref()->%*) {


See perlref for the full documentation.

Note: in Perl version 5.20 and 5.22, this syntax is considered experimental, so you need

use feature 'postderef';
no warnings 'experimental::postderef';

at the top of any file that uses it. Perl 5.24 and later don't require any pragmas for this feature.

Get method arguments using Spring AOP?

if your using @Aspect an option is add this method inside your Aspect and send the JoinPoint and the name of parameter you need.

private Object getParameter(ProceedingJoinPoint joinPoint, String parameterName) {
    Object valueParameter = null;
    if (Objects.nonNull(joinPoint) && joinPoint.getSignature() instanceof MethodSignature
            && Objects.nonNull(parameterName) ) {
        MethodSignature method = (MethodSignature)joinPoint.getSignature();
        String[] parameters = method.getParameterNames();
        for (int t = 0; t< parameters.length; t++) {
            if( Objects.nonNull(parameters[t]) && parameters[t].equals(parameterName)) {
                Object[] obj = joinPoint.getArgs();
                valueParameter = obj[t];
    return valueParameter;

and the call example:

Object parameterObject = getParameter(joinPoint, "nameClient");
if ( Objects.nonNull(parameterObject) ) {
    String parametro = String.valueOf(parameterObject);

Only need know the type of object for convert

Difference between database and schema

Schema in SQL Server is an object that conceptually holds definitions for other database objects such as tables,views,stored procedures etc.

How to check if a number is between two values?

Tests whether windowsize is greater than 500 and lesser than 600 meaning that neither values 500 or 600 itself will result in the condition becoming true.

if (windowsize > 500 && windowsize < 600) {
  // ...

How to write log file in c#?

public static void WriteLog(string strLog)
        StreamWriter log;
        FileStream fileStream = null;
        DirectoryInfo logDirInfo = null;
        FileInfo logFileInfo;

        string logFilePath = "C:\\Logs\\";
        logFilePath = logFilePath + "Log-" + System.DateTime.Today.ToString("MM-dd-yyyy") + "." + "txt";           
        logFileInfo = new FileInfo(logFilePath);
        logDirInfo = new DirectoryInfo(logFileInfo.DirectoryName);
        if (!logDirInfo.Exists) logDirInfo.Create();
        if (!logFileInfo.Exists)
            fileStream = logFileInfo.Create();
            fileStream = new FileStream(logFilePath, FileMode.Append);
        log = new StreamWriter(fileStream);

Refer Link:

Create SQL script that create database and tables

Yes, you can add as many SQL statements into a single script as you wish. Just one thing to note: the order matters. You can't INSERT into a table until you CREATE it; you can't set a foreign key until the primary key is inserted.

Replace a value if null or undefined in JavaScript

Destructuring solution

Question content may have changed, so I'll try to answer thoroughly.

Destructuring allows you to pull values out of anything with properties. You can also define default values when null/undefined and name aliases.

const options = {
    filters : {
        firstName : "abc"

const {filters: {firstName = "John", lastName = "Smith"}} = options

// firstName = "abc"
// lastName = "Smith"

NOTE: Capitalization matters

If working with an array, here is how you do it.

In this case, name is extracted from each object in the array, and given its own alias. Since the object might not exist = {} was also added.

const options = {
    filters: [{
        name: "abc",
        value: "lots"

const {filters:[{name : filter1 = "John"} = {}, {name : filter2 = "Smith"} = {}]} = options

// filter1 = "abc"
// filter2 = "Smith"

More Detailed Tutorial

Browser Support 92% July 2020

Ternary operator ?: vs if...else

In C A ternary operator " ? : " is available to construct conditional expressions of the form

exp1 ? exp2:exp3

where exp1,exp2 and exp3 are expressions

for Example


        in the above example x value will be assigned to b;

This can be written using if..else statement as follows

            if (a>b)

**Hence there is no difference between these two. This for the programmer to write easily, but for compiler both are same.*

What is the difference between syntax and semantics in programming languages?

The syntax of a programming language is the form of its expressions, statements, and program units. Its semantics is the meaning of those expressions, statements, and program units. For example, the syntax of a Java while statement is

while (boolean_expr) statement

The semantics of this statement form is that when the current value of the Boolean expression is true, the embedded statement is executed. Then control implicitly returns to the Boolean expression to repeat the process. If the Boolean expression is false, control transfers to the statement following the while construct.

How to do a redirect to another route with react-router?

1) react-router > V5 useHistory hook:

If you have React >= 16.8 and functional components you can use the useHistory hook from react-router.

import React from 'react';
import { useHistory } from 'react-router-dom';

const YourComponent = () => {
    const history = useHistory();

    const handleClick = () => {

    return (
            <button onClick={handleClick} type="button" />

export default YourComponent;

2) react-router > V4 withRouter HOC:

As @ambar mentioned in the comments, React-router has changed their code base since their V4. Here are the documentations - official, withRouter

import React, { Component } from 'react';
import { withRouter } from "react-router-dom";

class YourComponent extends Component {
    handleClick = () => {

    render() {
        return (
                <button onClick={this.handleClick} type="button">

export default withRouter(YourComponent);

3) React-router < V4 with browserHistory

You can achieve this functionality using react-router BrowserHistory. Code below:

import React, { Component } from 'react';
import { browserHistory } from 'react-router';

export default class YourComponent extends Component {
    handleClick = () => {

    render() {
        return (
                <button onClick={this.handleClick} type="button">

4) Redux connected-react-router

If you have connected your component with redux, and have configured connected-react-router all you have to do is this.props.history.push("/new/url"); ie, you don't need withRouter HOC to inject history to the component props.

// reducers.js
import { combineReducers } from 'redux';
import { connectRouter } from 'connected-react-router';

export default (history) => combineReducers({
    router: connectRouter(history),
    ... // rest of your reducers

// configureStore.js
import { createBrowserHistory } from 'history';
import { applyMiddleware, compose, createStore } from 'redux';
import { routerMiddleware } from 'connected-react-router';
import createRootReducer from './reducers';
export const history = createBrowserHistory();

export default function configureStore(preloadedState) {
    const store = createStore(
        createRootReducer(history), // root reducer with router state
                routerMiddleware(history), // for dispatching history actions
                // ... other middlewares ...

    return store;

// set up other redux requirements like for eg. in index.js
import { Provider } from 'react-redux';
import { Route, Switch } from 'react-router';
import { ConnectedRouter } from 'connected-react-router';
import configureStore, { history } from './configureStore';
const store = configureStore(/* provide initial state if any */)

    <Provider store={store}>
        <ConnectedRouter history={history}>
            <> { /* your usual react-router v4/v5 routing */ }
                    <Route exact path="/yourPath" component={YourComponent} />

// YourComponent.js
import React, { Component } from 'react';
import { connect } from 'react-redux';

class YourComponent extends Component {
    handleClick = () => {

    render() {
        return (
            <button onClick={this.handleClick} type="button">


export default connect(mapStateToProps = {}, mapDispatchToProps = {})(YourComponent);

Undefined reference to `sin`

I had the same problem, which went away after I listed my library last: gcc prog.c -lm

jQuery scrollTop not working in Chrome but working in Firefox

maybe you mean top: 0

$('a#gotop').click(function() {
  $("html").animate({ top: 0 }, "slow", function() { 
                                           alert('Animation complete.'); });
  //return false;

from animate docs

.animate( properties, [ duration ], [ easing ], [ callback ] )
properties A map of CSS properties that the animation will move toward.

or $(window).scrollTop() ?

$('a#gotop').click(function() {
  $("html").animate({ top: $(window).scrollTop() }, "slow", function() { 
                                                              alert('Animation complete.'); });
  //return false;

Locking pattern for proper use of .NET MemoryCache

I assume this code has concurrency issues:

Actually, it's quite possibly fine, though with a possible improvement.

Now, in general the pattern where we have multiple threads setting a shared value on first use, to not lock on the value being obtained and set can be:

  1. Disastrous - other code will assume only one instance exists.
  2. Disastrous - the code that obtains the instance is not can only tolerate one (or perhaps a certain small number) concurrent operations.
  3. Disastrous - the means of storage is not thread-safe (e.g. have two threads adding to a dictionary and you can get all sorts of nasty errors).
  4. Sub-optimal - the overall performance is worse than if locking had ensured only one thread did the work of obtaining the value.
  5. Optimal - the cost of having multiple threads do redundant work is less than the cost of preventing it, especially since that can only happen during a relatively brief period.

However, considering here that MemoryCache may evict entries then:

  1. If it's disastrous to have more than one instance then MemoryCache is the wrong approach.
  2. If you must prevent simultaneous creation, you should do so at the point of creation.
  3. MemoryCache is thread-safe in terms of access to that object, so that is not a concern here.

Both of these possibilities have to be thought about of course, though the only time having two instances of the same string existing can be a problem is if you're doing very particular optimisations that don't apply here*.

So, we're left with the possibilities:

  1. It is cheaper to avoid the cost of duplicate calls to SomeHeavyAndExpensiveCalculation().
  2. It is cheaper not to avoid the cost of duplicate calls to SomeHeavyAndExpensiveCalculation().

And working that out can be difficult (indeed, the sort of thing where it's worth profiling rather than assuming you can work it out). It's worth considering here though that most obvious ways of locking on insert will prevent all additions to the cache, including those that are unrelated.

This means that if we had 50 threads trying to set 50 different values, then we'll have to make all 50 threads wait on each other, even though they weren't even going to do the same calculation.

As such, you're probably better off with the code you have, than with code that avoids the race-condition, and if the race-condition is a problem, you quite likely either need to handle that somewhere else, or need a different caching strategy than one that expels old entries†.

The one thing I would change is I'd replace the call to Set() with one to AddOrGetExisting(). From the above it should be clear that it probably isn't necessary, but it would allow the newly obtained item to be collected, reducing overall memory use and allowing a higher ratio of low generation to high generation collections.

So yeah, you could use double-locking to prevent concurrency, but either the concurrency isn't actually a problem, or your storing the values in the wrong way, or double-locking on the store would not be the best way to solve it.

*If you know only one each of a set of strings exists, you can optimise equality comparisons, which is about the only time having two copies of a string can be incorrect rather than just sub-optimal, but you'd want to be doing very different types of caching for that to make sense. E.g. the sort XmlReader does internally.

†Quite likely either one that stores indefinitely, or one that makes use of weak references so it will only expel entries if there are no existing uses.

What happens if you mount to a non-empty mount point with fuse?

force it with -l

    sudo umount -l ${HOME}/mount_dir

When to use RDLC over RDL reports?

I have always thought the different between RDL and RDLC is that RDL are used for SQL Server Reporting Services and RDLC are used in Visual Studio for client side reporting. The implemenation and editor are almost identical. RDL stands for Report Defintion Language and RDLC Report Definition Language Client-side.

I hope that helps.

How do I use cx_freeze?

I'm really not sure what you're doing to get that error, it looks like you're trying to run cx_Freeze on its own, without arguments. So here is a short step-by-step guide on how to do it in windows (Your screenshot looks rather like the windows command line, so I'm assuming that's your platform)

  1. Write your file. Your script above looks correct so it should work, assuming that your script exists.

  2. Open the command line (Start -> Run -> "cmd")

  3. Go to the location of your file and run python build


  1. There may be a problem with the name of your script. "" contains upper case letters, which might cause confusion since windows' file names are not case sensitive, but python is. My approach is to always use lower case for scripts to avoid any conflicts.

  2. Make sure that python is on your PATH (read

  3. Make sure are are looking at the new cx_Freeze documentation. Google often seems to bring up the old docs.

How to split a string to 2 strings in C

If you're open to changing the original string, you can simply replace the delimiter with \0. The original pointer will point to the first string and the pointer to the character after the delimiter will point to the second string. The good thing is you can use both pointers at the same time without allocating any new string buffers.

Remove a file from a Git repository without deleting it from the local filesystem

A more generic solution:

  1. Edit .gitignore file.

    echo mylogfile.log >> .gitignore

  2. Remove all items from index.

    git rm -r -f --cached .

  3. Rebuild index.

    git add .

  4. Make new commit

    git commit -m "Removed mylogfile.log"

How to create a timer using tkinter?

I just created a simple timer using the MVP pattern (however it may be overkill for that simple project). It has quit, start/pause and a stop button. Time is displayed in HH:MM:SS format. Time counting is implemented using a thread that is running several times a second and the difference between the time the timer has started and the current time.

Source code on github

How to programmatically set drawableLeft on Android button?

Worked for me. To set drawable at the right

tvBioLive.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_close_red_400_24dp, 0)

How might I extract the property values of a JavaScript object into an array?

var dataArray = Object.keys(dataObject).map(function(k){return dataObject[k]});

Get Selected value from dropdown using JavaScript


var e = document.getElementById("mySelect");
var selectedOp = e.options[e.selectedIndex].text;

How to find Oracle Service Name

Thanks to this thread (

select sys_context('userenv','service_name') from dual;

It can be executed with a regular user account, no need for sysdba rights

Eclipse: How do you change the highlight color of the currently selected method/expression?

For those working in Titanium Studio, the item is a little different: It's under the "Titanium Studio" Themes tab.

The color to change is the "Selection" one in the top right.

enter image description here

How do I render a shadow?

All About margins

this works in Android, but did not test it in ios

import React, { PureComponent } from 'react'
import PropTypes from 'prop-types'
import { View, Platform } from 'react-native'
import EStyleSheet from 'react-native-extended-stylesheet'

const styles = EStyleSheet.create({
    wrapper: {
        margin: '-1.4rem'
    shadow: {
        padding: '1.4rem',
        margin: '1.4rem',
        borderRadius: 4,
        borderWidth: 0,
        borderColor: 'transparent',{
            ios: {
                shadowColor: 'rgba(0,0,0, 0.4)',
                shadowOffset: { height: 1, width: 1 },
                shadowOpacity: 0.7,
                shadowRadius: '1.4rem'
            android: {
                elevation: '1.4rem'
    container: {
        padding: 10,
        margin: '-1.4rem',
        borderRadius: 4,
        borderWidth: 0,
        borderColor: '#Fff',
        backgroundColor: '#fff'

class ShadowWrapper extends PureComponent {
    static propTypes = {
        children: PropTypes.oneOfType([

    render () {
        return (
            View style={styles.wrapper}
                View style={styles.shadow}
                    View style={styles.container}

export default ShadowWrapper

How do I prevent Eclipse from hanging on startup?

I did this:

  1. cd to .metadata.plugins\org.eclipse.core.resources
  2. remove the file .snap
  3. Noticed the Progress tab was doing something every few seemed stuck
  5. Open eclipse again.

Using -refresh or -clean when starting eclipse did not help.

How to drop SQL default constraint without knowing its name?

Expanded solution (takes table schema into account):

-- Drop default contstraint for SchemaName.TableName.ColumnName
DECLARE @schema_name NVARCHAR(256)
DECLARE @table_name NVARCHAR(256)
DECLARE @col_name NVARCHAR(256)
DECLARE @Command  NVARCHAR(1000)

set @schema_name = N'SchemaName'
set @table_name = N'TableName'
set @col_name = N'ColumnName'

SELECT @Command = 'ALTER TABLE [' + @schema_name + '].[' + @table_name + '] DROP CONSTRAINT ' +
 FROM sys.tables t   
  JOIN sys.default_constraints d       
   ON d.parent_object_id = t.object_id  
  JOIN sys.schemas s
        ON s.schema_id = t.schema_id
  JOIN    sys.columns c      
   ON c.object_id = t.object_id      
    AND c.column_id = d.parent_column_id
 WHERE = @table_name
    AND = @schema_name 
  AND = @col_name

EXECUTE (@Command)

Jackson enum Serializing and DeSerializer

Actual Answer:

The default deserializer for enums uses .name() to deserialize, so it's not using the @JsonValue. So as @OldCurmudgeon pointed out, you'd need to pass in {"event": "FORGOT_PASSWORD"} to match the .name() value.

An other option (assuming you want the write and read json values to be the same)...

More Info:

There is (yet) another way to manage the serialization and deserialization process with Jackson. You can specify these annotations to use your own custom serializer and deserializer:

@JsonSerialize(using = MySerializer.class)
@JsonDeserialize(using = MyDeserializer.class)
public final class MyClass {

Then you have to write MySerializer and MyDeserializer which look like this:


public final class MySerializer extends JsonSerializer<MyClass>
    public void serialize(final MyClass yourClassHere, final JsonGenerator gen, final SerializerProvider serializer) throws IOException, JsonProcessingException
        // here you'd write data to the stream with gen.write...() methods



public final class MyDeserializer extends<MyClass>
    public MyClass deserialize(final JsonParser parser, final DeserializationContext context) throws IOException, JsonProcessingException
        // then you'd do something like parser.getInt() or whatever to pull data off the parser
        return null;


Last little bit, particularly for doing this to an enum JsonEnum that serializes with the method getYourValue(), your serializer and deserializer might look like this:

public void serialize(final JsonEnum enumValue, final JsonGenerator gen, final SerializerProvider serializer) throws IOException, JsonProcessingException

public JsonEnum deserialize(final JsonParser parser, final DeserializationContext context) throws IOException, JsonProcessingException
    final String jsonValue = parser.getText();
    for (final JsonEnum enumValue : JsonEnum.values())
        if (enumValue.getYourValue().equals(jsonValue))
            return enumValue;
    return null;

How to check if anonymous object has a method?

One way to do it must be if (typeof myObj.prop1 != "undefined") {...}

Best way to access a control on another form in Windows Forms?

public void Enable_Usercontrol1()
    UserControl1 usercontrol1 = new UserControl1();
    usercontrol1.Enabled = true;
    Put this Anywhere in your Form and Call it by Enable_Usercontrol1();
    Also, Make sure the Usercontrol1 Modifiers is Set to Protected Internal

How can I create a Windows .exe (standalone executable) using Java/Eclipse?

Java doesn't natively allow building of an exe, that would defeat its purpose of being cross-platform.

AFAIK, these are your options:

  1. Make a runnable JAR. If the system supports it and is configured appropriately, in a GUI, double clicking the JAR will launch the app. Another option would be to write a launcher shell script/batch file which will start your JAR with the appropriate parameters

  2. There also executable wrappers - see How can I convert my Java program to an .exe file?

See also: Convert Java to EXE: Why, When, When Not and How

automatically execute an Excel macro on a cell change

Handle the Worksheet_Change event or the Workbook_SheetChange event.

The event handlers take an argument "Target As Range", so you can check if the range that's changing includes the cell you're interested in.

Where does Jenkins store configuration files for the jobs it runs?

On Linux one can find the home directory of Jenkins looking for a file, that Jenkins' home contains, e.g.:

$ find / -name "config.xml" | grep "jenkins"

How do I create a self-signed certificate for code signing on Windows?

Roger's answer was very helpful.

I had a little trouble using it, though, and kept getting the red "Windows can't verify the publisher of this driver software" error dialog. The key was to install the test root certificate with

certutil -addstore Root Demo_CA.cer

which Roger's answer didn't quite cover.

Here is a batch file that worked for me (with my .inf file, not included). It shows how to do it all from start to finish, with no GUI tools at all (except for a few password prompts).

REM Demo of signing a printer driver with a self-signed test certificate.
REM Run as administrator (else devcon won't be able to try installing the driver)
REM Use a single 'x' as the password for all certificates for simplicity.

PATH %PATH%;"c:\Program Files\Microsoft SDKs\Windows\v7.1\Bin";"c:\Program Files\Microsoft SDKs\Windows\v7.0\Bin";c:\WinDDK\7600.16385.1\bin\selfsign;c:\WinDDK\7600.16385.1\Tools\devcon\amd64

makecert -r -pe -n "CN=Demo_CA" -ss CA -sr CurrentUser ^
   -a sha256 -cy authority -sky signature ^
   -sv Demo_CA.pvk Demo_CA.cer

makecert -pe -n "CN=Demo_SPC" -a sha256 -cy end ^
   -sky signature ^
   -ic Demo_CA.cer -iv Demo_CA.pvk ^
   -sv Demo_SPC.pvk Demo_SPC.cer

pvk2pfx -pvk Demo_SPC.pvk -spc Demo_SPC.cer ^
   -pfx Demo_SPC.pfx ^
   -po x

inf2cat /drv:driver /os:XP_X86,Vista_X64,Vista_X86,7_X64,7_X86 /v

signtool sign /d "description" /du "" ^
   /f Demo_SPC.pfx ^
   /p x ^
   /v driver\

certutil -addstore Root Demo_CA.cer

rem Needs administrator. If this command works, the driver is properly signed.
devcon install driver\demoprinter.inf LPTENUM\Yoyodyne_IndustriesDemoPrinter_F84F

rem Now uninstall the test driver and certificate.
devcon remove driver\demoprinter.inf LPTENUM\Yoyodyne_IndustriesDemoPrinter_F84F

certutil -delstore Root Demo_CA

Error: "Adb connection Error:An existing connection was forcibly closed by the remote host"

Window->Show View->device (if not found ->Other->Device) in right most side, there is arrow, click that, you will see reset adb, just click and enjoy!! It worked for me.

Can we have multiple <tbody> in same <table>?

Yes you can use them, for example I use them to more easily style groups of data, like this:

thead th { width: 100px; border-bottom: solid 1px #ddd; font-weight: bold; }_x000D_
tbody:nth-child(odd) { background: #f5f5f5;  border: solid 1px #ddd; }_x000D_
tbody:nth-child(even) { background: #e5e5e5;  border: solid 1px #ddd; }
        <tr><td>Customer 1</td><td>#1</td><td>January</td></tr>_x000D_
        <tr><td>Customer 1</td><td>#2</td><td>April</td></tr>_x000D_
        <tr><td>Customer 1</td><td>#3</td><td>March</td></tr>_x000D_
        <tr><td>Customer 2</td><td>#1</td><td>January</td></tr>_x000D_
        <tr><td>Customer 2</td><td>#2</td><td>April</td></tr>_x000D_
        <tr><td>Customer 2</td><td>#3</td><td>March</td></tr>_x000D_
        <tr><td>Customer 3</td><td>#1</td><td>January</td></tr>_x000D_
        <tr><td>Customer 3</td><td>#2</td><td>April</td></tr>_x000D_
        <tr><td>Customer 3</td><td>#3</td><td>March</td></tr>_x000D_

You can view an example here. It'll only work in newer browsers, but that's what I'm supporting in my current application, you can use the grouping for JavaScript etc. The main thing is it's a convenient way to visually group the rows to make the data much more readable. There are other uses of course, but as far as applicable examples, this one is the most common one for me.

Making PHP var_dump() values display one line per value

For devs needing something that works in the view source and the CLI, especially useful when debugging unit tests.

echo vd([['foo'=>1, 'bar'=>2]]);

function vd($in) {
  return "\n" . preg_replace("/=>[\r\n\s]+/", "=> ", ob_get_clean());


array(1) {
  [0] => array(2) {
    'foo' => int(1)
    'bar' => int(2)

Getting JavaScript object key list

var obj = {
   key1: 'value1',
   key2: 'value2',
   key3: 'value3',
   key4: 'value4'


Sum rows in data.frame or matrix

The rowSums function (as Greg mentions) will do what you want, but you are mixing subsetting techniques in your answer, do not use "$" when using "[]", your code should look something more like:

data$new <- rowSums( data[,43:167] )

If you want to use a function other than sum, then look at ?apply for applying general functions accross rows or columns.

Read each line of txt file to new array element

$file = __DIR__."/file1.txt";
$f = fopen($file, "r");
$array1 = array();

while ( $line = fgets($f, 1000) )
    $nl = mb_strtolower($line,'UTF-8');
    $array1[] = $nl;


How to mock location on device?

I've had success with the following code. Albeit it got me a single lock for some reason (even if I've tried different LatLng pairs), it worked for me. mLocationManager is a LocationManager which is hooked up to a LocationListener:

private void getMockLocation()
      "requiresNetwork" == "",
      "requiresSatellite" == "",
      "requiresCell" == "",
      "hasMonetaryCost" == "",
      "supportsAltitude" == "",
      "supportsSpeed" == "",
      "supportsBearing" == "",


    Location newLocation = new Location(LocationManager.GPS_PROVIDER);

    newLocation.setLatitude (/* TODO: Set Some Lat */);
    newLocation.setLongitude(/* TODO: Set Some Lng */);





iFrame src change event detection?

If you have no control over the page and wish to watch for some kind of change then the modern method is to use MutationObserver

An example of its use, watching for the src attribute to change of an iframe

new MutationObserver(function(mutations) {_x000D_
  mutations.some(function(mutation) {_x000D_
    if (mutation.type === 'attributes' && mutation.attributeName === 'src') {_x000D_
      console.log('Old src: ', mutation.oldValue);_x000D_
      console.log('New src: ',;_x000D_
      return true;_x000D_
    return false;_x000D_
}).observe(document.body, {_x000D_
  attributes: true,_x000D_
  attributeFilter: ['src'],_x000D_
  attributeOldValue: true,_x000D_
  characterData: false,_x000D_
  characterDataOldValue: false,_x000D_
  childList: false,_x000D_
  subtree: true_x000D_
setTimeout(function() {_x000D_
  document.getElementsByTagName('iframe')[0].src = '';_x000D_
}, 3000);
<iframe src=""></iframe>

Output after 3 seconds

MutationRecord {oldValue: "", attributeNamespace: null, attributeName: "src", nextSibling: null, previousSibling: null…}
Old src:
New src: 

On jsFiddle

Posted answer here as original question was closed as a duplicate of this one.

C# catch a stack overflow exception

Yes from CLR 2.0 stack overflow is considered a non-recoverable situation. So the runtime still shut down the process.

For details please see the documentation

Functions that return a function

This is super useful in real life.

Working with Express.js

So your regular express route looks like this:

function itWorksHandler( req, res, next ) {
  res.send("It works!");

router.get("/check/works", itWorksHandler );

But what if you need to add some wrapper, error handler or smth?

Then you invoke your function off a wrapper.

function loggingWrapper( req, res, next, yourFunction ) {
  try {
    yourFunction( req, res );
  } catch ( err ) {
    console.error( err );
    next( err );

router.get("/check/works", function( req, res, next ) {
  loggingWrapper( req, res, next, itWorksHandler );

Looks complicated? Well, how about this:

function function loggingWrapper( yourFunction ) => ( req, res, next ) {
  try {
    yourFunction( req, res, next );
  } catch ( err ) {
    console.error( err );
    next( err );

router.get("/check/works", loggingWrapper( itWorksHandler ) );

See at the end you're passing a function loggingWrapper having one argument as another function itWorksHandler, and your loggingWrapper returns a new function which takes req, res, next as arguments.

force client disconnect from server with and nodejs

You can do socket = undefined in erase which socket you have connected. So when want to connected do socket(url)

So it will look like this

const socketClient = require('');

let socket;

// Connect to server
socket = socketClient(url)

// When want to disconnect
socket = undefined;

Format a Go string without printing?

1. Simple strings

For "simple" strings (typically what fits into a line) the simplest solution is using fmt.Sprintf() and friends (fmt.Sprint(), fmt.Sprintln()). These are analogous to the functions without the starter S letter, but these Sxxx() variants return the result as a string instead of printing them to the standard output.

For example:

s := fmt.Sprintf("Hi, my name is %s and I'm %d years old.", "Bob", 23)

The variable s will be initialized with the value:

Hi, my name is Bob and I'm 23 years old.

Tip: If you just want to concatenate values of different types, you may not automatically need to use Sprintf() (which requires a format string) as Sprint() does exactly this. See this example:

i := 23
s := fmt.Sprint("[age:", i, "]") // s will be "[age:23]"

For concatenating only strings, you may also use strings.Join() where you can specify a custom separator string (to be placed between the strings to join).

Try these on the Go Playground.

2. Complex strings (documents)

If the string you're trying to create is more complex (e.g. a multi-line email message), fmt.Sprintf() becomes less readable and less efficient (especially if you have to do this many times).

For this the standard library provides the packages text/template and html/template. These packages implement data-driven templates for generating textual output. html/template is for generating HTML output safe against code injection. It provides the same interface as package text/template and should be used instead of text/template whenever the output is HTML.

Using the template packages basically requires you to provide a static template in the form of a string value (which may be originating from a file in which case you only provide the file name) which may contain static text, and actions which are processed and executed when the engine processes the template and generates the output.

You may provide parameters which are included/substituted in the static template and which may control the output generation process. Typical form of such parameters are structs and map values which may be nested.


For example let's say you want to generate email messages that look like this:

Hi [name]!

Your account is ready, your user name is: [user-name]

You have the following roles assigned:
[role#1], [role#2], ... [role#n]

To generate email message bodies like this, you could use the following static template:

const emailTmpl = `Hi {{.Name}}!

Your account is ready, your user name is: {{.UserName}}

You have the following roles assigned:
{{range $i, $r := .Roles}}{{if $i}}, {{end}}{{.}}{{end}}

And provide data like this for executing it:

data := map[string]interface{}{
    "Name":     "Bob",
    "UserName": "bob92",
    "Roles":    []string{"dbteam", "uiteam", "tester"},

Normally output of templates are written to an io.Writer, so if you want the result as a string, create and write to a bytes.Buffer (which implements io.Writer). Executing the template and getting the result as string:

t := template.Must(template.New("email").Parse(emailTmpl))
buf := &bytes.Buffer{}
if err := t.Execute(buf, data); err != nil {
s := buf.String()

This will result in the expected output:

Hi Bob!

Your account is ready, your user name is: bob92

You have the following roles assigned:
dbteam, uiteam, tester

Try it on the Go Playground.

Also note that since Go 1.10, a newer, faster, more specialized alternative is available to bytes.Buffer which is: strings.Builder. Usage is very similar:

builder := &strings.Builder{}
if err := t.Execute(builder, data); err != nil {
s := builder.String()

Try this one on the Go Playground.

Note: you may also display the result of a template execution if you provide os.Stdout as the target (which also implements io.Writer):

t := template.Must(template.New("email").Parse(emailTmpl))
if err := t.Execute(os.Stdout, data); err != nil {

This will write the result directly to os.Stdout. Try this on the Go Playground.

CSS centred header image

you don't need to set the width of header in css, just put the background image as center using this code:

background: url("images/logo.png") no-repeat top center;

or you can just use img tag and put align="center" in the div

API Gateway CORS: no 'Access-Control-Allow-Origin' header

If anyone else is running into this still - I was able to track down the root cause in my application.

If you are running API-Gateway with custom Authorizers - API-Gateway will send a 401 or 403 back before it actually hits your server. By default - API-Gateway is NOT configured for CORS when returning 4xx from a custom authorizer.

Also - if you happen to be getting a status code of 0 or 1 from a request running through API Gateway, this is probably your issue.

To fix - in the API Gateway configuration - go to "Gateway Responses", expand "Default 4XX" and add a CORS configuration header there. i.e.

Access-Control-Allow-Origin: '*'

Make sure to re-deploy your gateway - and voila!

Remove a git commit which has not been pushed

git reset --hard origin/master

to reset it to whatever the origin was at.

This was posted by @bdonlan in the comments. I added this answer for people who don't read comments.

Array from dictionary keys in swift

Array from dictionary keys in Swift

componentArray = [String] (dict.keys)

Where can I download the jar for org.apache.http package?

At the Maven repo, there are samples to add the dependency in maven, sbt, gradle, etc.

ie for Maven, you just create a project, for example

mvn archetype:generate -DarchetypeGroupId=org.apache.maven.archetypes -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.4

then look at the pom.xml, then at the library at the dependencies xml element:


For sbt do something like

sbt new scala/hello-world.g8

then edit the build.sbt to add the library

libraryDependencies += "org.apache.httpcomponents" % "httpcore" % "4.4.11"