Programs & Examples On #Weblogic8.x

The 8.x (July 2003) release of WebLogic Server, a Java EE application server suite from Oracle. It's part of their Oracle Fusion Middleware product.

How do I keep the screen on in my App?


getWindow is a method defined for activities, and won't require you to find a View first.

Place a button right aligned

This would solve it.

<input type="button" value="Text Here..." style="float: right;">

Good luck with your code!

ORA-12528: TNS Listener: all appropriate instances are blocking new connections. Instance "CLRExtProc", status UNKNOWN

sqlplus "/as sysdba"
alter system disable restricted session;

or maybe

shutdown abort;

or maybe

lsnrctl stop

lsnrctl start

Use LINQ to get items in one List<>, that are not in another List<>

Here is a working example that get IT skills that a job candidate does not already have.

//Get a list of skills from the Skill table
IEnumerable<Skill> skillenum = skillrepository.Skill;
//Get a list of skills the candidate has                   
IEnumerable<CandSkill> candskillenum = candskillrepository.CandSkill
       .Where(p => p.Candidate_ID == Candidate_ID);             
//Using the enum lists with LINQ filter out the skills not in the candidate skill list
IEnumerable<Skill> skillenumresult = skillenum.Where(p => !candskillenum.Any(p2 => p2.Skill_ID == p.Skill_ID));
//Assign the selectable list to a viewBag
ViewBag.SelSkills = new SelectList(skillenumresult, "Skill_ID", "Skill_Name", 1);

CSS: styled a checkbox to look like a button, is there a hover?

it looks like you need a rule very similar to your checked rule

#ck-button input:hover + span {

and for hover and clicked state:

#ck-button input:checked:hover + span {

the order is important though.

How to get JSON data from the URL (REST API) to UI using jQuery or plain JavaScript?

You can use us jquery function getJson :

    $.getJSON('/api/rest/abc', function(data) {

How to put img inline with text

This should display the image inline:

.content-dir-item img.mail {
    display: inline-block;
    *display: inline; /* for older IE */
    *zoom: 1; /* for older IE */

C++ - How to append a char to char*?

The function name does not reflect the semantic of the function. In fact you do not append a character. You create a new character array that contains the original array plus the given character. So if you indeed need a function that appends a character to a character array I would write it the following way

bool AppendCharToCharArray( char *array, size_t n, char c )
    size_t sz = std::strlen( array );

    if ( sz + 1 < n ) 
        array[sz] = c;
        array[sz + 1] = '\0';

    return ( sz + 1 < n );

If you need a function that will contain a copy of the original array plus the given character then it could look the following way

char * CharArrayPlusChar( const char *array, char c )
    size_t sz = std::strlen( array );
    char *s = new char[sz + 2];

    std::strcpy( s, array );
    s[sz] = c;
    s[sz + 1] = '\0';

    return ( s );

Angular, content type is not being sent with $http

    url: 'http://localhost:8080/example/teste',
    dataType: 'json',
    method: 'POST',
    data: '',
    headers: {
        "Content-Type": "application/json"

    $scope.response = response;
    $scope.error = error;

Try like this.

Git Bash won't run my python files?

Add following line in you .bashrc file

# Environment path setting #
export PATH=/c/Python27:/c/Python27/Scripts:$PATH

Access Control Origin Header error using Axios in React Web throwing error in Chrome

I imagine everyone knows what cors is and what it is for. In a simple way and for example if you use nodejs and express for the management, enable it is like this


app.use (
   cors ({
     origin: "*",
    ... more

And for the problem of browser requests locally, it is only to install this extension of google chrome.

Name: Allow CORS: Access-Control-Allow-Origin

This allows you to enable and disable cros in local, and problem solved.

Converting bool to text in C++

If you decide to use macros (or are using C on a future project) you should add parenthesis around the 'b' in the macro expansion (I don't have enough points yet to edit other people's content):

#define BOOL_STR(b) ((b)?"true":"false")

This is a defensive programming technique that protects against hidden order-of-operations errors; i.e., how does this evaluate for all compilers?

1 == 2 ? "true" : "false"

compared to

(1 == 2) ? "true" : "false"

How to check version of python modules?

In Summary:

conda list   

(It will provide all the libraries along with version details).


pip show tensorflow

(It gives complete library details).

Getting started with Haskell

If you only have experience with imperative/OO languages, I suggest using a more conventional functional language as a stepping stone. Haskell is really different and you have to understand a lot of different concepts to get anywhere. I suggest tackling a ML-style language (like e.g. F#) first.

Trigger a button click with JavaScript on the Enter key in a text box

To trigger a search every time the enter key is pressed, use this:

$(document).keypress(function(event) {
    var keycode = (event.keyCode ? event.keyCode : event.which);
    if (keycode == '13') {

How can I get a channel ID from YouTube?

2017 Update: Henry's answer may be a little off the mark here. If you look for data-channel-external-id in the source code you may find more than one ID, and only the first occurrence is actually correct. Get the channel_id used in <link rel="alternate" type="application/rss+xml" title="RSS" href="<VALUE_HERE"> instead.

Where does error CS0433 "Type 'X' already exists in both A.dll and B.dll " come from?

A super quick and handy fix is to abuse Visual Studio's incredible intellisense by temporarily referencing the class somewhere.


System.Runtime.CompilerServices.ExtensionAttribute x = null;

When building or hovering the cursor over the line you can view the following error:

'System.Runtime.CompilerServices.ExtensionAttribute' exists in both 'C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll'

This tells you the two sources causing the conflict immediately.

System.Core.dll is the .dll file that you want to keep, so delete the other one.

I found mine sitting in the bin directory, but it may be elsewhere in the project.

As a matter of fact this is worth bearing in mind, because since the bin directory might not be included as part of the TFS change-set, it can explain why checking in your changes doesn't resolve the issue for other members of your team.

Deserialize JSON string to c# object

This may be useful:

var serializer = new JavaScriptSerializer();
dynamic jsonObject = serializer.Deserialize<dynamic>(json);

Where "json" is the string that contains the JSON values. Then to retrieve the values from the jsonObject you may use

myProperty = Convert.MyPropertyType(jsonObject["myProperty"]);

Changing MyPropertyType to the proper type (ToInt32, ToString, ToBoolean, etc).

How to suppress "unused parameter" warnings in C?

In MSVC to suppress a particular warning it is enough to specify the it's number to compiler as /wd#. My CMakeLists.txt contains such the block:

    Add_definitions (/W4 /wd4512 /wd4702 /wd4100 /wd4510 /wd4355 /wd4127)
    Add_definitions (/D_CRT_SECURE_NO_WARNINGS)
    Add_definitions (-Wall -W -pedantic)
Else ()
    Message ("Unknown compiler")
Endif ()

Now I can not say what exactly /wd4512 /wd4702 /wd4100 /wd4510 /wd4355 /wd4127 mean, because I do not pay any attention to MSVC for three years, but they suppress superpedantic warnings that does not influence the result.

Can RDP clients launch remote applications and not desktops

This is called "seamless" mode. rdesktop, the RDP client for Unix, is capable of this. From the manpage:

   -A     Enable SeamlessRDP. In this mode, rdesktop creates a X11 window for each window on the server
          side.  This  mode  requires  the  SeamlessRDP  server side component, which is available from
  When using this option, you  should  specify  a  startup
          shell which launches the desired application through SeamlessRDP.

See mentioned Cendio website for more information.

Difference between a theta join, equijoin and natural join

Natural is a subset of Equi which is a subset of Theta.

If I use the = sign on a theta join is it exactly the same as just using a natural join???

Not necessarily, but it would be an Equi. Natural means you are matching on all similarly named columns, Equi just means you are using '=' exclusively (and not 'less than', like, etc)

This is pure academia though, you could work with relational databases for years and never hear anyone use these terms.

how to delete a specific row in codeigniter?

It will come in the url so you can get it by two ways. Fist one

<td><?php echo anchor('textarea/delete_row', 'DELETE', 'id="$row->id"'); ?></td>
$id = $this->input->get('id');

2nd one.

$id = $this->uri->segment(3);

But in the second method you have to count the no. of segments in the url that on which no. your id come. 2,3,4 etc. then you have to pass. then in the ();

Check if user is using IE

I've placed this code in the document ready function and it only triggers in internet explorer. Tested in Internet Explorer 11.

var ua = window.navigator.userAgent;
ms_ie = /MSIE|Trident/.test(ua);
if ( ms_ie ) {
    //Do internet explorer exclusive behaviour here

How to copy a file from one directory to another using PHP?

You can use both rename() and copy().

I tend to prefer to use rename if I no longer require the source file to stay in its location.

How to add RSA key to authorized_keys file?

Make sure when executing Michael Krelin's solution you do the following

cat <your_public_key_file> >> ~/.ssh/authorized_keys

Note the double > without the double > the existing contents of authorized_keys will be over-written (nuked!) and that may not be desirable

The best node module for XML parsing

You can try xml2js. It's a simple XML to JavaScript object converter. It gets your XML converted to a JS object so that you can access its content with ease.

Here are some other options:

  1. libxmljs
  2. xml-stream
  3. xmldoc
  4. cheerio – implements a subset of core jQuery for XML (and HTML)

I have used xml2js and it has worked fine for me. The rest you might have to try out for yourself.

How to print environment variables to the console in PowerShell?

The following is works best in my opinion:

Get-Item Env:PATH
  1. It's shorter and therefore a little bit easier to remember than Get-ChildItem. There's no hierarchy with environment variables.
  2. The command is symmetrical to one of the ways that's used for setting environment variables with Powershell. (EX: Set-Item -Path env:SomeVariable -Value "Some Value")
  3. If you get in the habit of doing it this way you'll remember how to list all Environment variables; simply omit the entry portion. (EX: Get-Item Env:)

I found the syntax odd at first, but things started making more sense after I understood the notion of Providers. Essentially PowerShell let's you navigate disparate components of the system in a way that's analogous to a file system.

What's the point of the trailing colon in Env:? Try listing all of the "drives" available through Providers like this:

PS> Get-PSDrive

I only see a few results... (Alias, C, Cert, D, Env, Function, HKCU, HKLM, Variable, WSMan). It becomes obvious that Env is simply another "drive" and the colon is a familiar syntax to anyone who's worked in Windows.

You can navigate the drives and pick out specific values:

Get-ChildItem C:\Windows
Get-Item C:
Get-Item Env:
Get-Item HKLM:

What is the difference between a deep copy and a shallow copy?

I haven't seen a short, easy to understand answer here--so I'll give it a try.

With a shallow copy, any object pointed to by the source is also pointed to by the destination (so that no referenced objects are copied).

With a deep copy, any object pointed to by the source is copied and the copy is pointed to by the destination (so there will now be 2 of each referenced object). This recurses down the object tree.

How do I monitor the computer's CPU, memory, and disk usage in Java?

Have a look at this very detailled article:

To get the percentage of CPU used, all you need is some simple maths:

MBeanServerConnection mbsc = ManagementFactory.getPlatformMBeanServer();

OperatingSystemMXBean osMBean = ManagementFactory.newPlatformMXBeanProxy(
mbsc, ManagementFactory.OPERATING_SYSTEM_MXBEAN_NAME, OperatingSystemMXBean.class);

long nanoBefore = System.nanoTime();
long cpuBefore = osMBean.getProcessCpuTime();

// Call an expensive task, or sleep if you are monitoring a remote process

long cpuAfter = osMBean.getProcessCpuTime();
long nanoAfter = System.nanoTime();

long percent;
if (nanoAfter > nanoBefore)
 percent = ((cpuAfter-cpuBefore)*100L)/
else percent = 0;

System.out.println("Cpu usage: "+percent+"%");

Note: You must import and not

Set TextView text from html-formatted string resource in XML

Android does not have a specification to indicate the type of resource string (e.g. text/plain or text/html). There is a workaround, however, that will allow the developer to specify this within the XML file.

  1. Define a custom attribute to specify that the android:text attribute is html.
  2. Use a subclassed TextView.

Once you define these, you can express yourself with HTML in xml files without ever having to call setText(Html.fromHtml(...)) again. I'm rather surprised that this approach is not part of the API.

This solution works to the degree that the Android studio simulator will display the text as rendered HTML.

enter image description here

res/values/strings.xml (the string resource as HTML)

<string name="app_name">TextViewEx</string>
<string name="string_with_html"><![CDATA[
       <em>Hello</em> <strong>World</strong>!

layout.xml (only the relevant parts)

Declare the custom attribute namespace, and add the android_ex:isHtml attribute. Also use the subclass of TextView.



res/values/attrs.xml (define the custom attributes for the subclass)

<declare-styleable name="TextViewEx">
    <attr name="isHtml" format="boolean"/>
    <attr name="android:text" />
</resources> (the subclass of TextView)

 package tv.twelvetone.samples.textviewex;

 import android.content.Context;
 import android.content.res.TypedArray;
 import android.text.Html;
 import android.util.AttributeSet;
 import android.widget.TextView;

public TextViewEx(Context context, @Nullable AttributeSet attrs) {
    super(context, attrs);
    TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.TextViewEx, 0, 0);
    try {
        boolean isHtml = a.getBoolean(R.styleable.TextViewEx_isHtml, false);
        if (isHtml) {
            String text = a.getString(R.styleable.TextViewEx_android_text);
            if (text != null) {
    } catch (Exception e) {
    } finally {

How to "Open" and "Save" using java

You may also want to consider the possibility of using SWT (another Java GUI library). Pros and cons of each are listed at:

Java Desktop application: SWT vs. Swing

Example of SOAP request authenticated with WS-UsernameToken

May be this post (Secure Metro JAX-WS UsernameToken Web Service with Signature, Encryption and TLS (SSL)) provides more insight. As they mentioned "Remember, unless password text or digested password is sent on a secured channel or the token is encrypted, neither password digest nor cleartext password offers no real additional security. "

Initialize a long in Java

  1. You need to add the L character to the end of the number to make Java recognize it as a long.

    long i = 12345678910L;
  2. Yes.

See Primitive Data Types which says "An integer literal is of type long if it ends with the letter L or l; otherwise it is of type int."

How to install pip with Python 3?

I was able to install pip for python 3 on Ubuntu just by running sudo apt-get install python3-pip.

Single quotes vs. double quotes in C or C++

Single quotes are for a single character. Double quotes are for a string (array of characters). You can use single quotes to build up a string one character at a time, if you like.

char myChar     = 'A';
char myString[] = "Hello Mum";
char myOtherString[] = { 'H','e','l','l','o','\0' };

JWT (Json Web Token) Audience "aud" versus Client_Id - What's the difference?

The JWT aud (Audience) Claim

According to RFC 7519:

The "aud" (audience) claim identifies the recipients that the JWT is intended for. Each principal intended to process the JWT MUST identify itself with a value in the audience claim. If the principal processing the claim does not identify itself with a value in the "aud" claim when this claim is present, then the JWT MUST be rejected. In the general case, the "aud" value is an array of case- sensitive strings, each containing a StringOrURI value. In the special case when the JWT has one audience, the "aud" value MAY be a single case-sensitive string containing a StringOrURI value. The interpretation of audience values is generally application specific. Use of this claim is OPTIONAL.

The Audience (aud) claim as defined by the spec is generic, and is application specific. The intended use is to identify intended recipients of the token. What a recipient means is application specific. An audience value is either a list of strings, or it can be a single string if there is only one aud claim. The creator of the token does not enforce that aud is validated correctly, the responsibility is the recipient's to determine whether the token should be used.

Whatever the value is, when a recipient is validating the JWT and it wishes to validate that the token was intended to be used for its purposes, it MUST determine what value in aud identifies itself, and the token should only validate if the recipient's declared ID is present in the aud claim. It does not matter if this is a URL or some other application specific string. For example, if my system decides to identify itself in aud with the string:, then it should only accept the JWT if the aud claim contains in its list of audience values.

Of course, recipients may choose to disregard aud, so this is only useful if a recipient would like positive validation that the token was created for it specifically.

My interpretation based on the specification is that the aud claim is useful to create purpose-built JWTs that are only valid for certain purposes. For one system, this may mean you would like a token to be valid for some features but not for others. You could issue tokens that are restricted to only a certain "audience", while still using the same keys and validation algorithm.

Since in the typical case a JWT is generated by a trusted service, and used by other trusted systems (systems which do not want to use invalid tokens), these systems simply need to coordinate the values they will be using.

Of course, aud is completely optional and can be ignored if your use case doesn't warrant it. If you don't want to restrict tokens to being used by specific audiences, or none of your systems actually will validate the aud token, then it is useless.

Example: Access vs. Refresh Tokens

One contrived (yet simple) example I can think of is perhaps we want to use JWTs for access and refresh tokens without having to implement separate encryption keys and algorithms, but simply want to ensure that access tokens will not validate as refresh tokens, or vice-versa.

By using aud, we can specify a claim of refresh for refresh tokens and a claim of access for access tokens upon creating these tokens. When a request is made to get a new access token from a refresh token, we need to validate that the refresh token was a genuine refresh token. The aud validation as described above will tell us whether the token was actually a valid refresh token by looking specifically for a claim of refresh in aud.

OAuth Client ID vs. JWT aud Claim

The OAuth Client ID is completely unrelated, and has no direct correlation to JWT aud claims. From the perspective of OAuth, the tokens are opaque objects.

The application which accepts these tokens is responsible for parsing and validating the meaning of these tokens. I don't see much value in specifying OAuth Client ID within a JWT aud claim.

How to hide element using Twitter Bootstrap and show it using jQuery?

Razz's answer is good if you're willing to rewrite what you have done.

Was in the same trouble and worked it out with the following:

 * The problem:
 * _x000D_
 * This script enhances jQuery's methods: show and hide dynamically._x000D_
 * If the element was hidden by bootstrap's css class 'hide', remove it first._x000D_
 * Do similar in overriding the method 'hide'._x000D_
!function($) {_x000D_
    "use strict";_x000D_
    var oldShowHide = {'show': $, 'hide': $.fn.hide};_x000D_
        show: function() {_x000D_
            this.each(function(index) {_x000D_
                var $element = $(this);_x000D_
                if ($element.hasClass('hide')) {_x000D_
        hide: function() {_x000D_
            this.each(function(index) {_x000D_
                var $element = $(this);_x000D_
                if ($element.hasClass('show')) {_x000D_

Throw it away when Bootstrap comes with a fix for this problem.

What is python's site-packages directory?

site-packages is just the location where Python installs its modules.

No need to "find it", python knows where to find it by itself, this location is always part of the PYTHONPATH (sys.path).

Programmatically you can find it this way:

import sys
site_packages = next(p for p in sys.path if 'site-packages' in p)
print site_packages


Black transparent overlay on image hover with only CSS?

.overlay didn't have a height or width and no content, and you can't hover over display:none.

I instead gave the div the same size and position as .image and changes RGBA value on hover.

.image { position: absolute; border: 1px solid black; width: 200px; height: 200px; z-index:1;}
.image img { max-width: 100%; max-height: 100%; }
.overlay { position: absolute; top: 0; left: 0; background:rgba(255,0,0,0); z-index: 200; width:200px; height:200px; }
.overlay:hover { background:rgba(255,0,0,.7); }

How to change the URI (URL) for a remote Git repository?

You can change the url by editing the config file. Go to your project root:

nano .git/config

Then edit the url field and set your new url. Save the changes. You can verify the changes by using the command.

git remote -v 

Cannot get to $rootScope

You can not ask for instance during configuration phase - you can ask only for providers.

var app = angular.module('modx', []);

// configure stuff
app.config(function($routeProvider, $locationProvider) {
  // you can inject any provider here

// run blocks$rootScope) {
  // you can inject any instance here

See for more info.

annotation to make a private method public only for test classes

dp4j has what you need. Essentially all you have to do is add dp4j to your classpath and whenever a method annotated with @Test (JUnit's annotation) calls a method that's private it will work (dp4j will inject the required reflection at compile-time). You may also use dp4j's @TestPrivates annotation to be more explicit.

If you insist on also annotating your private methods you may use Google's @VisibleForTesting annotation.

@Nullable annotation usage

It makes it clear that the method accepts null values, and that if you override the method, you should also accept null values.

It also serves as a hint for code analyzers like FindBugs. For example, if such a method dereferences its argument without checking for null first, FindBugs will emit a warning.

error: unknown type name ‘bool’

C90 does not support the boolean data type.

C99 does include it with this include:

#include <stdbool.h>

Best way to parse command-line parameters?

I have never liked ruby like option parsers. Most developers that used them never write a proper man page for their scripts and end up with pages long options not organized in a proper way because of their parser.

I have always preferred Perl's way of doing things with Perl's Getopt::Long.

I am working on a scala implementation of it. The early API looks something like this:

def print_version() = () => println("version is 0.2")

def main(args: Array[String]) {
  val (options, remaining) = OptionParser.getOptions(args,
      "-f|--flag"       -> 'flag,
      "-s|--string=s"   -> 'string,
      "-i|--int=i"      -> 'int,
      "-f|--float=f"    -> 'double,
      "-p|-procedure=p" -> { () => println("higher order function" }
      "-h=p"            -> { () => print_synopsis() }
      "--help|--man=p"  -> { () => launch_manpage() },
      "--version=p"     -> print_version,

So calling script like this:

$ script hello -f --string=mystring -i 7 --float 3.14 --p --version world -- --nothing

Would print:

higher order function
version is 0.2

And return:

remaining = Array("hello", "world", "--nothing")

options = Map('flag   -> true,
              'string -> "mystring",
              'int    -> 7,
              'double -> 3.14)

The project is hosted in github scala-getoptions.

What is the most efficient way to deep clone an object in JavaScript?

I use the npm clone library. Apparently it also works in the browser.

let a = clone(b)

Override body style for content in an iframe

Override another domain iframe CSS

By using part of SimpleSam5's answer, I achieved this with a few of Tawk's chat iframes (their customization interface is fine but I needed further customizations).

In this particular iframe that shows up on mobile devices, I needed to hide the default icon and place one of my background images. I did the following:

Tawk_API.onLoad = function() {
// without a specific API, you may try a similar load function
// perhaps with a setTimeout to ensure the iframe's content is fully loaded
     $("<style type='text/css'>"+
       "#tawkchat-status-text-container {"+
         "background: url( no-repeat center center blue;"+
         "background-size: 100%;"+
       "} "+
       "#tawkchat-status-icon {display:none} </style>")

I do not own any Tawk's domain and this worked for me, thus you may do this even if it's not from the same parent domain (despite Jeremy Becker's comment on Sam's answer).

Copy rows from one table to another, ignoring duplicates

DISTINCT is the keyword you're looking for.

In MSSQL, copying unique rows from a table to another can be done like this:

INTO newTable
FROM srcTable

The column_name is the column you're searching the unique values from.

Tested and works.

Using NSLog for debugging

NSLog(@"%@", digit);

what is shown in console?

How to test if a string is JSON or not?

There are probably tests you can do, for instance if you know that the JSON returned is always going to be surrounded by { and } then you could test for those characters, or some other hacky method. Or you could use the JS library to try and parse it and test if it succeeds.

I would however suggest a different approach. Your PHP script currently returns JSON if the call is successful, but something else if it is not. Why not always return JSON?


Successful call:

{ "status": "success", "data": [ <your data here> ] }

Erroneous call:

{ "status": "error", "error": "Database not found" }

This would make writing your client side JS much easier - all you have to do is check the "status" member and the act accordingly.

Vue 2 - Mutating props vue-warn

Vue3 has a really good solution. Spent hours to reach there. But it worked really good.

On parent template


The child component

app.component('user-name', {
      props: {
      firstName: String,
      lastName: String
template: `


This was the only solution which did two way binding. I like that first two answers were addressing in good way to use SYNC and Emitting update events, and compute property getter setter, but that was heck of a Job to do and I did not like to work so hard.

Failure [INSTALL_FAILED_ALREADY_EXISTS] when I tried to update my application

It might mean the application is already installed for another user on your device. Users share applications. I don't know why they do but they do. So if one user updates an application is updated for the other user also. If you uninstall on one, it doesn't remove the app from the system on the other.

TensorFlow ValueError: Cannot feed value of shape (64, 64, 3) for Tensor u'Placeholder:0', which has shape '(?, 64, 64, 3)'

Powder's comment may go undetected like I missed it so many times,. So with the hope of making it more visible, I will re-iterate his point.

Sometimes using image = array(img).reshape(a,b,c,d) will reshape alright but from experience, my kernel crashes every time I try to use the new dimension in an operation. The safest to use is

np.expand_dims(img, axis=0)

It works perfect every time. I just can't explain why. This link has a great explanation and examples regarding its usage.

How to find controls in a repeater header or footer

As noted in the comments, this only works AFTER you've DataBound your repeater.

To find a control in the header:

lblControl = repeater1.Controls[0].Controls[0].FindControl("lblControl");

To find a control in the footer:

lblControl = repeater1.Controls[repeater1.Controls.Count - 1].Controls[0].FindControl("lblControl");

With extension methods

public static class RepeaterExtensionMethods
    public static Control FindControlInHeader(this Repeater repeater, string controlName)
        return repeater.Controls[0].Controls[0].FindControl(controlName);

    public static Control FindControlInFooter(this Repeater repeater, string controlName)
        return repeater.Controls[repeater.Controls.Count - 1].Controls[0].FindControl(controlName);

Declare a const array

If you declare an array behind an IReadOnlyList interface you get a constant array with constant values that is declared at runtime:

public readonly IReadOnlyList<string> Titles = new [] {"German", "Spanish", "Corrects", "Wrongs" };

Available in .NET 4.5 and higher.

How do I convert a TimeSpan to a formatted string?

Use String.Format() with multiple parameters.

using System;

namespace TimeSpanFormat
    class Program
        static void Main(string[] args)
            TimeSpan dateDifference = new TimeSpan(0, 0, 6, 32, 445);
            string formattedTimeSpan = string.Format("{0:D2} hrs, {1:D2} mins, {2:D2} secs", dateDifference.Hours, dateDifference.Minutes, dateDifference.Seconds);

How do I get a value of a <span> using jQuery?

Assuming you intended it to read id="item1", you need

$('#item1 span').text()

How to push elements in JSON from javascript array

I think you want to make objects from array and combine it with an old object (BODY.recipients.values), if it's then you may do it using $.extent (because you are using jQuery/tagged) method after prepare the object from array

var BODY = {
    "recipients": {
        "values": []
    "subject": 'TitleOfSubject',
    "body": 'This is the message body.'

var values = [],
names = ['sheikh', 'muhammed', 'Answer', 'Uddin', 'Heera']; // for testing
for (var ln = 0; ln < names.length; ln++) {
    var item1 = {
        "person": { "_path": "/people/"+names[ln] }

// Now merge with BODY
$.extend(BODY.recipients.values, values);


This IP, site or mobile application is not authorized to use this API key

For the latest version of the API the exact opposite seems to be true for me.

When calling the url<address>&key=<key> I was getting the following error

You must use an API key to authenticate each request to Google Maps Platform APIs. For additional information, please refer to

Once I switched the order to<key>&address=<address> it worked fine.

Note that the error message received above was the message I got when going directly to the URL in the browser. When I called the API from a software program I received an HTML response with basically the following message:

We're sorry... but your computer or network may be sending automated queries. To protect our users, we can't process your request right now.

Sorting an array in C?

In your particular case the fastest sort is probably the one described in this answer. It is exactly optimized for an array of 6 ints and uses sorting networks. It is 20 times (measured on x86) faster than library qsort. Sorting networks are optimal for sort of fixed length arrays. As they are a fixed sequence of instructions they can even be implemented easily by hardware.

Generally speaking there is many sorting algorithms optimized for some specialized case. The general purpose algorithms like heap sort or quick sort are optimized for in place sorting of an array of items. They yield a complexity of O(n.log(n)), n being the number of items to sort.

The library function qsort() is very well coded and efficient in terms of complexity, but uses a call to some comparizon function provided by user, and this call has a quite high cost.

For sorting very large amount of datas algorithms have also to take care of swapping of data to and from disk, this is the kind of sorts implemented in databases and your best bet if you have such needs is to put datas in some database and use the built in sort.

How do I use T-SQL's Case/When?

   WHEN xyz.something = 1 THEN 'SOMETEXT'
   WHEN xyz.somethingelse = 1 THEN 'SOMEOTHERTEXT'
   WHEN xyz.somethingelseagain = 2 THEN 'SOMEOTHERTEXTGOESHERE'
   END AS ColumnName;

jQuery UI: Datepicker set year range dropdown to 100 years

I wanted to implement the datepicker to select the birthdate and I had troubles changing the yearRange as it doesn't seemed to work with my version (1.5). I updated to the newest jquery-ui datepicker version here:

Then I found out they provide this very helpful on-the-fly tool, so you can config your whole datepicker and see what settings you have to use.

That's how I found out that the option


is the option I was looking for and I didn't find any results searching the web.

So for other users: If you also want to provide the datepicker to change the birthdate, I suggest to use this code options:

    startView: 2,
    maxViewMode: 2,
    daysOfWeekHighlighted: "1,2",
    defaultViewDate: { year: new Date().getFullYear()-20, month: 01, day: 01 }

When opening the datepicker you will start with the view to select the years, 20 years ago relative to the current year.

Difference between static class and singleton pattern?

To illustrate Jon's point what's shown below cannot be done if Logger was a static class.The class SomeClass expects an instance of ILogger implementation to be passed into its constructor.

Singleton class is important for dependency injection to be possible.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication2
    class Program
        static void Main(string[] args)

            var someClass = new SomeClass(Logger.GetLogger());


    public class SomeClass 
        public SomeClass(ILogger MyLogger)


    public class Logger : ILogger
        private static Logger _logger;
        private Logger() { }

        public static Logger GetLogger()
            if (_logger==null)
                _logger = new Logger();

            return _logger;

        public void Log()



    public interface ILogger
         void Log();

ImageView in circular through xml

I have a simple solution. Create a new Image asset by right clicking your package name and selecting New->Image asset. Enter name (any name) and path (location of image in your system). Then click Next and Finish. If you enter name of image as 'img', a round image with the name 'img_round' is created automatically in mipmap folder.

Then, do this :


Your preview may still show a rectangular image. But if you run the app on your device, it will be round.

Create a list from two object lists with linq

You need something like a full outer join. System.Linq.Enumerable has no method that implements a full outer join, so we have to do it ourselves.

var dict1 = list1.ToDictionary(l1 => l1.Name);
var dict2 = list2.ToDictionary(l2 => l2.Name);
    //get the full list of names.
var names = dict1.Keys.Union(dict2.Keys).ToList();
    //produce results
var result = names
.Select( name =>
  Person p1 = dict1.ContainsKey(name) ? dict1[name] : null;
  Person p2 = dict2.ContainsKey(name) ? dict2[name] : null;
      //left only
  if (p2 == null)
    p1.Change = 0;
    return p1;
      //right only
  if (p1 == null)
    p2.Change = 0;
    return p2;
  p2.Change = p2.Value - p1.Value;
  return p2;

Getting the client IP address: REMOTE_ADDR, HTTP_X_FORWARDED_FOR, what else could be useful?

I've ported Grant Burton's PHP code to an ASP.Net static method callable against the HttpRequestBase. It will optionally skip through any private IP ranges.

public static class ClientIP
    // based on
    public static string ClientIPFromRequest(this HttpRequestBase request, bool skipPrivate)
        foreach (var item in s_HeaderItems)
            var ipString = request.Headers[item.Key];

        if (String.IsNullOrEmpty(ipString))

        if (item.Split)
            foreach (var ip in ipString.Split(','))
                if (ValidIP(ip, skipPrivate))
                    return ip;
            if (ValidIP(ipString, skipPrivate))
                return ipString;

    return request.UserHostAddress;

private static bool ValidIP(string ip, bool skipPrivate)
    IPAddress ipAddr;

    ip = ip == null ? String.Empty : ip.Trim();

    if (0 == ip.Length
        || false == IPAddress.TryParse(ip, out ipAddr)
        || (ipAddr.AddressFamily != AddressFamily.InterNetwork
            && ipAddr.AddressFamily != AddressFamily.InterNetworkV6))
        return false;

    if (skipPrivate && ipAddr.AddressFamily == AddressFamily.InterNetwork)
        var addr = IpRange.AddrToUInt64(ipAddr);
        foreach (var range in s_PrivateRanges)
            if (range.Encompasses(addr))
                return false;

    return true;

/// <summary>
/// Provides a simple class that understands how to parse and
/// compare IP addresses (IPV4) ranges.
/// </summary>
private sealed class IpRange
    private readonly UInt64 _start;
    private readonly UInt64 _end;

    public IpRange(string startStr, string endStr)
        _start = ParseToUInt64(startStr);
        _end = ParseToUInt64(endStr);

    public static UInt64 AddrToUInt64(IPAddress ip)
        var ipBytes = ip.GetAddressBytes();
        UInt64 value = 0;

        foreach (var abyte in ipBytes)
            value <<= 8;    // shift
            value += abyte;

        return value;

    public static UInt64 ParseToUInt64(string ipStr)
        var ip = IPAddress.Parse(ipStr);
        return AddrToUInt64(ip);

    public bool Encompasses(UInt64 addrValue)
        return _start <= addrValue && addrValue <= _end;

    public bool Encompasses(IPAddress addr)
        var value = AddrToUInt64(addr);
        return Encompasses(value);

private static readonly IpRange[] s_PrivateRanges =
    new IpRange[] { 
            new IpRange("",""),
            new IpRange("",""),
            new IpRange("",""),
            new IpRange("",""),
            new IpRange("",""),
            new IpRange("",""),
            new IpRange("",""),
            new IpRange("","")

/// <summary>
/// Describes a header item (key) and if it is expected to be 
/// a comma-delimited string
/// </summary>
private sealed class HeaderItem
    public readonly string Key;
    public readonly bool Split;

    public HeaderItem(string key, bool split)
        Key = key;
        Split = split;

// order is in trust/use order top to bottom
private static readonly HeaderItem[] s_HeaderItems =
    new HeaderItem[] { 
            new HeaderItem("HTTP_CLIENT_IP",false),
            new HeaderItem("HTTP_X_FORWARDED_FOR",true),
            new HeaderItem("HTTP_X_FORWARDED",false),
            new HeaderItem("HTTP_X_CLUSTER_CLIENT_IP",false),
            new HeaderItem("HTTP_FORWARDED_FOR",false),
            new HeaderItem("HTTP_FORWARDED",false),
            new HeaderItem("HTTP_VIA",false),
            new HeaderItem("REMOTE_ADDR",false)

SQL subquery with COUNT help

FROM eventsTable e
           select columnName,count(columnName) as colCount
           from eventsTable e2 
          group by columnName
           ) as cnt on cnt.columnName = e.columnName
WHERE e.columnName='Business'

-- Added space

Java RegEx meta character (.) and ordinary dot?

Perl-style regular expressions (which the Java regex engine is more or less based upon) treat the following characters as special characters:

.^$|*+?()[{\ have special meaning outside of character classes,

]^-\ have special meaning inside of character classes ([...]).

So you need to escape those (and only those) symbols depending on context (or, in the case of character classes, place them in positions where they can't be misinterpreted).

Needlessly escaping other characters may work, but some regex engines will treat this as syntax errors, for example \_ will cause an error in .NET.

Some others will lead to false results, for example \< is interpreted as a literal < in Perl, but in egrep it means "word boundary".

So write -?\d+\.\d+\$ to match 1.50$, -2.00$ etc. and [(){}[\]] for a character class that matches all kinds of brackets/braces/parentheses.

If you need to transform a user input string into a regex-safe form, use java.util.regex.Pattern.quote.

Further reading: Jan Goyvaert's blog RegexGuru on escaping metacharacters

Remove Datepicker Function dynamically

Destroy the datepicker's instance when you don't want it and create new instance whenever necessary.

I know this is ugly but only this seems to be working...

Check this out

 $("#ddlSearchType").change(function () {
        if ($(this).val() == "Required Date" || $(this).val() == "Submitted Date") {

          else {

How to calculate UILabel height dynamically?

Try this

// UILabel *myLabel;

CGSize labelSize = [myLabel.text sizeWithFont:myLabel.font 

CGFloat labelHeight = labelSize.height;

int lines = [myLabel.text sizeWithFont:myLabel.font 
             // '16' is font size


int lines = labelHeight/16;

NSLog(@"lines count : %i \n\n",lines);  


int lines = [myLabel.text sizeWithFont:myLabel.font 
                         lineBreakMode:UILineBreakModeWordWrap].height /myLabel.font.pointSize; //fetching font size from font

By Using Categories, Just Create the category class named as



No more tension about the height calculation. Please review the below implementation.

Updates for iOS7 & Above,iOS 7 below : Dynamically calculate the UILabel height

#define SYSTEM_VERSION_EQUAL_TO(v)                  ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedSame)
#define SYSTEM_VERSION_GREATER_THAN(v)              ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedDescending)
#define SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(v)  ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedAscending)
#define SYSTEM_VERSION_LESS_THAN(v)                 ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedAscending)
#define SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(v)     ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedDescending)
#define iOS7_0 @"7.0"


#import <UIKit/UIKit.h>
@interface UILabel (UILabelDynamicHeight)

#pragma mark - Calculate the size the Multi line Label

    /* Calculate the size of the Multi line Label */

 *  Returns the size of the Label
 *  @param aLabel To be used to calculte the height
 *  @return size of the Label



#import "UILabel+UILabelDynamicHeight.h"
@implementation UILabel (UILabelDynamicHeight)

#pragma mark - Calculate the size,bounds,frame of the Multi line Label

/* Calculate the size,bounds,frame of the Multi line Label */

 *  Returns the size of the Label
 *  @param aLabel To be used to calculte the height
 *  @return size of the Label

    //Label text
    NSString *aLabelTextString = [self text];

    //Label font
    UIFont *aLabelFont = [self font];

    //Width of the Label
    CGFloat aLabelSizeWidth = self.frame.size.width;

        //version < 7.0

        return [aLabelTextString sizeWithFont:aLabelFont
                            constrainedToSize:CGSizeMake(aLabelSizeWidth, MAXFLOAT)
        //version >= 7.0

        //Return the calculated size of the Label
        return [aLabelTextString boundingRectWithSize:CGSizeMake(aLabelSizeWidth, MAXFLOAT)
                                                        NSFontAttributeName : aLabelFont


    return [self bounds].size;


C++ Singleton design pattern

#define INS(c) private:void operator=(c const&){};public:static c& I(){static c _instance;return _instance;}


   class CCtrl
        virtual ~CCtrl(void);


Multiple scenarios @RequestMapping produces JSON/XML together with Accept or ResponseEntity

All your problems are that you are mixing content type negotiation with parameter passing. They are things at different levels. More specific, for your question 2, you constructed the response header with the media type your want to return. The actual content negotiation is based on the accept media type in your request header, not response header. At the point the execution reaches the implementation of the method getPersonFormat, I am not sure whether the content negotiation has been done or not. Depends on the implementation. If not and you want to make the thing work, you can overwrite the request header accept type with what you want to return.

return new ResponseEntity<>(PersonFactory.createPerson(), httpHeaders, HttpStatus.OK);

Getting the actual usedrange

This function gives all 4 limits of the used range:

Function FindUsedRangeLimits()
    Set Sheet = ActiveSheet

    ' Display the range's rows and columns.
    row_min = Sheet.UsedRange.Row
    row_max = row_min + Sheet.UsedRange.Rows.Count - 1
    col_min = Sheet.UsedRange.Column
    col_max = col_min + Sheet.UsedRange.Columns.Count - 1

    MsgBox "Rows " & row_min & " - " & row_max & vbCrLf & _
           "Columns: " & col_min & " - " & col_max
    LastCellBeforeBlankInColumn = True
End Function

Download a file with Android, and showing the progress in a ProgressDialog

Yes the code above will work .But if you are updating your progressbar in onProgressUpdate of Asynctask and you press back button or finish your activity AsyncTask looses its track with your UI .And when you go back to your activity, even if download is running in background you will see no update on progressbar. So on OnResume() try to run a thread like runOnUIThread with a timer task that updates ur progressbar with values updating from the AsyncTask running background.

private void updateProgressBar(){
    Runnable runnable = new updateProgress();
    background = new Thread(runnable);

public class updateProgress implements Runnable {
    public void run() {
            //while (!Thread.currentThread().isInterrupted()) {
            try {
                Message msg = new Message();
                progress = getProgressPercentage();        
            } catch (InterruptedException e) {
            } catch (Exception e) {

private Handler handler = new Handler(){
    public void handleMessage(Message msg) {

Don't forget to Destroy the thread when ur activity is not visible.

private void destroyRunningThreads() {
    if (background != null) {

How to convert NSData to byte array in iPhone?

You can't declare an array using a variable so Byte byteData[len]; won't work. If you want to copy the data from a pointer, you also need to memcpy (which will go through the data pointed to by the pointer and copy each byte up to a specified length).


NSData *data = [NSData dataWithContentsOfFile:filePath];
NSUInteger len = [data length];
Byte *byteData = (Byte*)malloc(len);
memcpy(byteData, [data bytes], len);

This code will dynamically allocate the array to the correct size (you must free(byteData) when you're done) and copy the bytes into it.

You could also use getBytes:length: as indicated by others if you want to use a fixed length array. This avoids malloc/free but is less extensible and more prone to buffer overflow issues so I rarely ever use it.

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:

Instance member cannot be used on type

It is saying you have an instance variable (the var is only visible/accessible when you have an instance of that class) and you are trying to use it in the context of a static scope (class method).

You can make your instance variable a class variable by adding static/class attribute.

You instantiate an instance of your class and call the instance method on that variable.

Pure CSS scroll animation

And for webkit enabled browsers I've had good results with:

.myElement {
    -webkit-overflow-scrolling: touch;
    scroll-behavior: smooth; // Added in from answer from Felix
    overflow-x: scroll;

This makes scrolling behave much more like the standard browser behavior - at least it works well on the iPhone we were testing on!

Hope that helps,


Manually raising (throwing) an exception in Python

How do I manually throw/raise an exception in Python?

Use the most specific Exception constructor that semantically fits your issue.

Be specific in your message, e.g.:

raise ValueError('A very specific bad thing happened.')

Don't raise generic exceptions

Avoid raising a generic Exception. To catch it, you'll have to catch all other more specific exceptions that subclass it.

Problem 1: Hiding bugs

raise Exception('I know Python!') # Don't! If you catch, likely to hide bugs.

For example:

def demo_bad_catch():
        raise ValueError('Represents a hidden bug, do not catch this')
        raise Exception('This is the exception you expect to handle')
    except Exception as error:
        print('Caught this error: ' + repr(error))

>>> demo_bad_catch()
Caught this error: ValueError('Represents a hidden bug, do not catch this',)

Problem 2: Won't catch

And more specific catches won't catch the general exception:

def demo_no_catch():
        raise Exception('general exceptions not caught by specific handling')
    except ValueError as e:
        print('we will not catch exception: Exception')

>>> demo_no_catch()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 3, in demo_no_catch
Exception: general exceptions not caught by specific handling

Best Practices: raise statement

Instead, use the most specific Exception constructor that semantically fits your issue.

raise ValueError('A very specific bad thing happened')

which also handily allows an arbitrary number of arguments to be passed to the constructor:

raise ValueError('A very specific bad thing happened', 'foo', 'bar', 'baz') 

These arguments are accessed by the args attribute on the Exception object. For example:

except ValueError as err:


('message', 'foo', 'bar', 'baz')    

In Python 2.5, an actual message attribute was added to BaseException in favor of encouraging users to subclass Exceptions and stop using args, but the introduction of message and the original deprecation of args has been retracted.

Best Practices: except clause

When inside an except clause, you might want to, for example, log that a specific type of error happened, and then re-raise. The best way to do this while preserving the stack trace is to use a bare raise statement. For example:

logger = logging.getLogger(__name__)

except AppError as error:
    raise                 # just this!
    # raise AppError      # Don't do this, you'll lose the stack trace!

Don't modify your errors... but if you insist.

You can preserve the stacktrace (and error value) with sys.exc_info(), but this is way more error prone and has compatibility problems between Python 2 and 3, prefer to use a bare raise to re-raise.

To explain - the sys.exc_info() returns the type, value, and traceback.

type, value, traceback = sys.exc_info()

This is the syntax in Python 2 - note this is not compatible with Python 3:

raise AppError, error, sys.exc_info()[2] # avoid this.
# Equivalently, as error *is* the second object:
raise sys.exc_info()[0], sys.exc_info()[1], sys.exc_info()[2]

If you want to, you can modify what happens with your new raise - e.g. setting new args for the instance:

def error():
    raise ValueError('oops!')

def catch_error_modify_message():
    except ValueError:
        error_type, error_instance, traceback = sys.exc_info()
        error_instance.args = (error_instance.args[0] + ' <modification>',)
        raise error_type, error_instance, traceback

And we have preserved the whole traceback while modifying the args. Note that this is not a best practice and it is invalid syntax in Python 3 (making keeping compatibility much harder to work around).

>>> catch_error_modify_message()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 3, in catch_error_modify_message
  File "<stdin>", line 2, in error
ValueError: oops! <modification>

In Python 3:

raise error.with_traceback(sys.exc_info()[2])

Again: avoid manually manipulating tracebacks. It's less efficient and more error prone. And if you're using threading and sys.exc_info you may even get the wrong traceback (especially if you're using exception handling for control flow - which I'd personally tend to avoid.)

Python 3, Exception chaining

In Python 3, you can chain Exceptions, which preserve tracebacks:

raise RuntimeError('specific message') from error

Be aware:

  • this does allow changing the error type raised, and
  • this is not compatible with Python 2.

Deprecated Methods:

These can easily hide and even get into production code. You want to raise an exception, and doing them will raise an exception, but not the one intended!

Valid in Python 2, but not in Python 3 is the following:

raise ValueError, 'message' # Don't do this, it's deprecated!

Only valid in much older versions of Python (2.4 and lower), you may still see people raising strings:

raise 'message' # really really wrong. don't do this.

In all modern versions, this will actually raise a TypeError, because you're not raising a BaseException type. If you're not checking for the right exception and don't have a reviewer that's aware of the issue, it could get into production.

Example Usage

I raise Exceptions to warn consumers of my API if they're using it incorrectly:

def api_func(foo):
    '''foo should be either 'baz' or 'bar'. returns something very useful.'''
    if foo not in _ALLOWED_ARGS:
        raise ValueError('{foo} wrong, use "baz" or "bar"'.format(foo=repr(foo)))

Create your own error types when apropos

"I want to make an error on purpose, so that it would go into the except"

You can create your own error types, if you want to indicate something specific is wrong with your application, just subclass the appropriate point in the exception hierarchy:

class MyAppLookupError(LookupError):
    '''raise this when there's a lookup error for my app'''

and usage:

if important_key not in resource_dict and not ok_to_be_missing:
    raise MyAppLookupError('resource is missing, and that is not ok.')

How to use a filter in a controller?

Inject $filter to your controller

function myCtrl($scope, $filter)

Then wherever you want to use that filter, just use it like this:


If you want to pass arguments to that filter, do it using separate parentheses:

function myCtrl($scope, $filter)

Where arg1 is the array you want to filter on and arg2 is the object used to filter.

MongoDB - admin user not authorized

Perhaps a quick example of how to change a current user will be helpful to somebody. This is what I was actually looking for.

Following advice of @JohnPetrone I added readWrite role to my admin user with grantRolesToUser

> use admin
> db.grantRolesToUser("admin",["readWrite"])
> show collections

How do I pass environment variables to Docker containers?

Another way is to use the powers of /usr/bin/env:

docker run ubuntu env DEBUG=1 path/to/

How to update (append to) an href in jquery?

var _href = $("a.directions-link").attr("href");
$("a.directions-link").attr("href", _href + '&saddr=50.1234567,-50.03452');

To loop with each()

$("a.directions-link").each(function() {
   var $this = $(this);       
   var _href = $this.attr("href"); 
   $this.attr("href", _href + '&saddr=50.1234567,-50.03452');

ng-repeat: access key and value for each object in array of objects

I think the problem is with the way you designed your data. To me in terms of semantics, it just doesn't make sense. What exactly is steps for?

Does it store the information of one company?

If that's the case steps should be an object (see KayakDave's answer) and each "step" should be an object property.

Does it store the information of multiple companies?

If that's the case, steps should be an array of objects.

$scope.steps=[{companyName: true, businessType: true},{companyName: false}]

In either case you can easily iterate through the data with one (two for 2nd case) ng-repeats.

change directory in batch file using variable

The set statement doesn't treat spaces the way you expect; your variable is really named Pathname[space] and is equal to [space]C:\Program Files.

Remove the spaces from both sides of the = sign, and put the value in double quotes:

set Pathname="C:\Program Files"

Also, if your command prompt is not open to C:\, then using cd alone can't change drives.


cd /d %Pathname%


pushd %Pathname%


Check if string is in a pandas dataframe

If there is any chance that you will need to search for empty strings,


will NOT work, as it will always return True.

Instead, use

    if '' in a["Names"].values

to accurately reflect whether or not a string is in a Series, including the edge case of searching for an empty string.

The model backing the 'ApplicationDbContext' context has changed since the database was created

I just solved a similar problem by deleting all files in the website folder and then republished it.

How to create a temporary directory and get the path / file name in Python

To expand on another answer, here is a fairly complete example which can cleanup the tmpdir even on exceptions:

import contextlib
import os
import shutil
import tempfile

def cd(newdir, cleanup=lambda: True):
    prevdir = os.getcwd()

def tempdir():
    dirpath = tempfile.mkdtemp()
    def cleanup():
    with cd(dirpath, cleanup):
        yield dirpath

def main():
    with tempdir() as dirpath:
        pass # do something here

Spring,Request method 'POST' not supported

Your user.jsp:

 <form:form action="profile/proffesional" modelAttribute="PROFESSIONAL">

In your controller class:

(make it as a meaning full method name..Hear i think you are insert record in DB.)

@RequestMapping(value = "proffessional", method = RequestMethod.POST)
    public @ResponseBody
    String proffessionalDetails(
            @ModelAttribute UserProfessionalForm professionalForm,
            BindingResult result, Model model) {

        UserProfileVO userProfileVO = new UserProfileVO();

        model.addAttribute("PROFESSIONAL", professionalForm);

        return "Your Professional Details Updated";


C: Run a System Command and Get Output?

You need some sort of Inter Process Communication. Use a pipe or a shared buffer.

Memory address of an object in C#

When you free that handle, the garbage collector is free to move the memory that was pinned. If you have a pointer to memory that's supposed to be pinned, and you un-pin that memory, then all bets are off. That this worked at all in 3.5 was probably just by luck. The JIT compiler and the runtime for 4.0 probably do a better job of object lifetime analysis.

If you really want to do this, you can use a try/finally to prevent the object from being un-pinned until after you've used it:

public static string Get(object a)
    GCHandle handle = GCHandle.Alloc(a, GCHandleType.Pinned);
        IntPtr pointer = GCHandle.ToIntPtr(handle);
        return "0x" + pointer.ToString("X");

Can't create handler inside thread which has not called Looper.prepare()

You create handler in background thread this way

private void createHandler() {
        Thread thread = new Thread() {
          public void run() {

               final Handler handler = new Handler();
               handler.postDelayed(new Runnable() {
                    public void run() {
                       // Do Work
                }, 2000);


How to set JAVA_HOME in Linux for all users

Step 1 - check the current java version by "echo $JAVA_HOME"

Step 2 - vim /etc/profile

Step 3 - At the end of file you will find export JAVA_HOME, we need to provide the new path here, make sure that it is not relative.

Step 4 - Save and exit :wq

Step 5 - "source /etc/profile/", this would execute the change

Step 6 - Again do a echo $JAVA_HOME - change would have been reflected.

How to disable PHP Error reporting in CodeIgniter?

Change CI index.php file to:

if ($_SERVER['SERVER_NAME'] == 'local_server_name') {
    define('ENVIRONMENT', 'development');
} else {
    define('ENVIRONMENT', 'production');

if (defined('ENVIRONMENT')){
    switch (ENVIRONMENT){
        case 'development':

        case 'testing':
        case 'production':

            exit('The application environment is not set correctly.');

IF PHP errors are off, but any MySQL errors are still going to show, turn these off in the /config/database.php file. Set the db_debug option to false:

$db['default']['db_debug'] = FALSE; 

Also, you can use active_group as development and production to match the environment

$active_group = 'development';

$db['development']['hostname'] = 'localhost';
$db['development']['username'] = '---';
$db['development']['password'] = '---';
$db['development']['database'] = '---';
$db['development']['dbdriver'] = 'mysql';
$db['development']['dbprefix'] = '';
$db['development']['pconnect'] = TRUE;

$db['development']['db_debug'] = TRUE;

$db['development']['cache_on'] = FALSE;
$db['development']['cachedir'] = '';
$db['development']['char_set'] = 'utf8';
$db['development']['dbcollat'] = 'utf8_general_ci';
$db['development']['swap_pre'] = '';
$db['development']['autoinit'] = TRUE;
$db['development']['stricton'] = FALSE;

$db['production']['hostname'] = 'localhost';
$db['production']['username'] = '---';
$db['production']['password'] = '---';
$db['production']['database'] = '---';
$db['production']['dbdriver'] = 'mysql';
$db['production']['dbprefix'] = '';
$db['production']['pconnect'] = TRUE;

$db['production']['db_debug'] = FALSE;

$db['production']['cache_on'] = FALSE;
$db['production']['cachedir'] = '';
$db['production']['char_set'] = 'utf8';
$db['production']['dbcollat'] = 'utf8_general_ci';
$db['production']['swap_pre'] = '';
$db['production']['autoinit'] = TRUE;
$db['production']['stricton'] = FALSE;

TOMCAT - HTTP Status 404

To get your program to run, please put jsp files under web-content and not under WEB-INF because in Eclipse the files are not accessed there by the server, so try starting the server and browsing to URL:


then your problem will be solved.

MySQL ON DUPLICATE KEY UPDATE for multiple rows insert in single query

Beginning with MySQL 8.0.19 you can use an alias for that row (see reference).

INSERT INTO beautiful (name, age)
    ('Helen', 24),
    ('Katrina', 21),
    ('Samia', 22),
    ('Hui Ling', 25),
    ('Yumie', 29)
    AS new
    age = new.age

For earlier versions use the keyword VALUES (see reference, deprecated with MySQL 8.0.20).

INSERT INTO beautiful (name, age)
    ('Helen', 24),
    ('Katrina', 21),
    ('Samia', 22),
    ('Hui Ling', 25),
    ('Yumie', 29)
    age = VALUES(age),

How to check whether a variable is a class or not?

This check is compatible with both Python 2.x and Python 3.x.

import six
isinstance(obj, six.class_types)

This is basically a wrapper function that performs the same check as in andrea_crotti answer.


>>> import datetime
>>> isinstance(, six.class_types)
>>> True
>>> isinstance(, six.class_types)
>>> False

Using CSS to affect div style inside iframe

In short no.

You can not apply CSS to HTML that is loaded in an iframe, unless you have control over the page loaded in the iframe due to cross-domain resource restrictions.

$(document).ready(function(){ Uncaught ReferenceError: $ is not defined

No need to use jQuery.noConflict and all

Try this instead:

// Replace line no. 87 (guessing from your chrome console) to the following


// All your code using $


If you still get error at line 87, like Uncaught reference error: jQuery is not defined, then you need to include jQuery file before using it, for which you can check the above answers

Validate email address textbox using JavaScript

You should use below regex which have tested all possible email combination

     function validate(email) {
            var reg = "^[a-zA-Z0-9]+(\.[_a-zA-Z0-9]+)*@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*(\.[a-zA-Z]{2,15})$";
            //var address = document.getElementById[email].value;
            if (reg.test(email) == false) 
                alert('Invalid Email Address');
                return (false);

Bonus tip if you're using this in Input tag than you can directly add the regex in that tag example

<input type="text"  

Above you can see two attribute required & pattern in

required make sure it input block have data @time of submit &
pattern make sure it input tag validate based in pattern(regex) @time of submit

For more info you can go throw doc

Reading a JSP variable from JavaScript

The cleanest way, as far as I know:

  1. add your JSP variable to an HTML element's data-* attribute
  2. then read this value via Javascript when required

My opinion regarding the current solutions on this SO page: reading "directly" JSP values using java scriplet inside actual javascript code is probably the most disgusting thing you could do. Makes me wanna puke. haha. Seriously, try to not do it.

The HTML part without JSP:

<body data-customvalueone="1st Interpreted Jsp Value" data-customvaluetwo="another Interpreted Jsp Value">
    Here is your regular page main content

The HTML part when using JSP:

<body data-customvalueone="${beanName.attrName}" data-customvaluetwo="${beanName.scndAttrName}">
    Here is your regular page main content

The javascript part (using jQuery for simplicity):

<script type="text/JavaScript" src="//"></script>
<script type="text/javascript">
        var valuePassedFromJSP = $("body").attr("data-customvalueone");
        var anotherValuePassedFromJSP = $("body").attr("data-customvaluetwo");

        alert(valuePassedFromJSP + " and " + anotherValuePassedFromJSP + " are the values passed from your JSP page");

And here is the jsFiddle to see this in action


Regex select all text between tags

To exclude the delimiting tags:


(?<=<pre>) looks for text after <pre>

(?=</pre>) looks for text before </pre>

Results will text inside pre tag

MySQL Select Date Equal to Today

Sounds like you need to add the formatting to the WHERE:

SELECT, DATE_FORMAT(users.signup_date, '%Y-%m-%d') 
FROM users 
WHERE DATE_FORMAT(users.signup_date, '%Y-%m-%d') = CURDATE()

See SQL Fiddle with Demo

Global variables in AngularJS

Example of AngularJS "global variables" using $rootScope:

Controller 1 sets the global variable:

function MyCtrl1($scope, $rootScope) {
    $ = 'anonymous'; 

Controller 2 reads the global variable:

function MyCtrl2($scope, $rootScope) {
    $scope.name2 = $; 

Here is a working jsFiddle:

init-param and context-param

<init-param> will be used if you want to initialize some parameter for a particular servlet. When request come to servlet first its init method will be called then doGet/doPost whereas if you want to initialize some variable for whole application you will need to use <context-param> . Every servlet will have access to the context variable.

IE8 support for CSS Media Query

Edited answer: IE understands just screen and print as import media. All other CSS supplied along with the import statement causes IE8 to ignore the import statement. Geco browser like safari or mozilla didn't have this problem.

C++ Structure Initialization

You can just initialize via a constructor:

struct address {
  address() : city("Hamilton"), prov("Ontario") {}
  int street_no;
  char *street_name;
  char *city;
  char *prov;
  char *postal_code;

How to make an image center (vertically & horizontally) inside a bigger div

The best way to center an image both vertically and horizontally, is to use two containers, and apply the following properties :

The outher container

  • should have display: table;

The inner container

  • should have display: table-cell;
  • should have vertical-align: middle;
  • should have text-align: center;

A demo

.outer-container {_x000D_
    display: table;_x000D_
    width: 80%; /* can be any width */_x000D_
    height: 120px; /* can be any height */_x000D_
    background: #ccc;_x000D_
.inner-container {_x000D_
    display: table-cell;_x000D_
    vertical-align: middle;_x000D_
    text-align: center;_x000D_
.inner-container img {_x000D_
    background: #fff;_x000D_
    padding : 10px;_x000D_
    border : 1px solid #000;_x000D_
<div class="outer-container">_x000D_
   <div class="inner-container">_x000D_
     <img src="" />_x000D_

Pandas convert string to int

You need add parameter errors='coerce' to function to_numeric:

ID = pd.to_numeric(ID, errors='coerce')

If ID is column:

df.ID = pd.to_numeric(df.ID, errors='coerce')

but non numeric are converted to NaN, so all values are float.

For int need convert NaN to some value e.g. 0 and then cast to int:

df.ID = pd.to_numeric(df.ID, errors='coerce').fillna(0).astype(np.int64)


df = pd.DataFrame({'ID':['4806105017087','4806105017087','CN414149']})
print (df)
0  4806105017087
1  4806105017087
2       CN414149

print (pd.to_numeric(df.ID, errors='coerce'))
0    4.806105e+12
1    4.806105e+12
2             NaN
Name: ID, dtype: float64

df.ID = pd.to_numeric(df.ID, errors='coerce').fillna(0).astype(np.int64)
print (df)
0  4806105017087
1  4806105017087
2              0

EDIT: If use pandas 0.25+ then is possible use integer_na:

df.ID = pd.to_numeric(df.ID, errors='coerce').astype('Int64')
print (df)
0  4806105017087
1  4806105017087
2            NaN

enum Values to NSString (iOS)

I didn't like putting the enum on the heap, without providing a heap function for translation. Here's what I came up with:

typedef enum {value1, value2, value3} myValue;
#define myValueString(enum) [@[@"value1",@"value2",@"value3"] objectAtIndex:enum]

This keeps the enum and string declarations close together for easy updating when needed.

Now, anywhere in the code, you can use the enum/macro like this:

myValue aVal = value2;
NSLog(@"The enum value is '%@'.", myValueString(aVal));

outputs: The enum value is 'value2'.

To guarantee the element indexes, you can always explicitly declare the start(or all) enum values.

enum {value1=0, value2=1, value3=2};

Invoking a static method using reflection

public class Add {
    static int add(int a, int b){
        return (a+b);

In the above example, 'add' is a static method that takes two integers as arguments.

Following snippet is used to call 'add' method with input 1 and 2.

Class myClass = Class.forName("Add");
Method method = myClass.getDeclaredMethod("add", int.class, int.class);
Object result = method.invoke(null, 1, 2);

Reference link.

How to disable Google asking permission to regularly check installed apps on my phone?

With the latest version of Lollipop, go into app. drawer and look for Google Settings. Scroll down to Security, tap iit to open, slide to the left the slider next to 'Improve harmful app. detection' to the left, then same for 'Scan device for security threats'. Exit out of that, and the annoying pop up will never appear again!

AngularJS disable partial caching on dev machine

Building on @Valentyn's answer a bit, here's one way to always automatically clear the cache whenever the ng-view content changes:$rootScope, $templateCache) {
   $rootScope.$on('$viewContentLoaded', function() {

How to run a function when the page is loaded?

Taking Darin's answer but jQuery style. (I know the user asked for javascript).

running fiddle

$(document).ready ( function(){

How to embed images in html email

I would strongly recommend using a library like PHPMailer to send emails.
It's easier and handles most of the issues automatically for you.

Regarding displaying embedded (inline) images, here's what's on their documentation:

Inline Attachments

There is an additional way to add an attachment. If you want to make a HTML e-mail with images incorporated into the desk, it's necessary to attach the image and then link the tag to it. For example, if you add an image as inline attachment with the CID my-photo, you would access it within the HTML e-mail with <img src="cid:my-photo" alt="my-photo" />.

In detail, here is the function to add an inline attachment:

$mail->AddEmbeddedImage(filename, cid, name);
//By using this function with this example's value above, results in this code:
$mail->AddEmbeddedImage('my-photo.jpg', 'my-photo', 'my-photo.jpg ');

To give you a more complete example of how it would work:

$mail = new PHPMailer(true); // the true param means it will throw exceptions on     errors, which we need to catch

$mail->IsSMTP(); // telling the class to use SMTP

try {
  $mail->Host       = ""; // SMTP server
  $mail->Port       = 25;                    // set the SMTP port
  $mail->SetFrom('[email protected]', 'First Last');
  $mail->AddAddress('[email protected]', 'John Doe');
  $mail->Subject = 'PHPMailer Test';

  $mail->AddEmbeddedImage("rocks.png", "my-attach", "rocks.png");
  $mail->Body = 'Your <b>HTML</b> with an embedded Image: <img src="cid:my-attach"> Here is an image!';

  $mail->AddAttachment(''); // this is a regular attachment (Not inline)
  echo "Message Sent OK<p></p>\n";
} catch (phpmailerException $e) {
  echo $e->errorMessage(); //Pretty error messages from PHPMailer
} catch (Exception $e) {
  echo $e->getMessage(); //Boring error messages from anything else!


Regarding your comment, you asked how to send HTML email with embedded images, so I gave you an example of how to do that.
The library I told you about can send emails using a lot of methods other than SMTP.
Take a look at the PHPMailer Example page for other examples.

One way or the other, if you don't want to send the email in the ways supported by the library, you can (should) still use the library to build the message, then you send it the way you want.

For example:

You can replace the line that send the email:


With this:

$mime_message = $mail->CreateBody(); //Retrieve the message content
echo $mime_message; // Echo it to the screen or send it using whatever method you want

Hope that helps. Let me know if you run into trouble using it.

How to improve Netbeans performance?

I use Windows 7. I suggest right-clicking the NetBeans shortcut, go to Properties, and on the Shortcut tab at the Target, add -J-Xmx1024m -J-Xms256m.

This sets the memory usage of the JVM. Xms is the minimal value, while Xmx is the max.

This is the value of target textfield:

"C:\Program Files\NetBeans 7.1\bin\netbeans.exe" --jdkhome "C:\Program Files\Java\jdk1.6.0_10" -J-Dorg.netbeans.modules.php.dbgp.level=400 -J-Xmx1024m -J-Xms256m

Since I add that attribute, my NetBeans run so fast!

Another way to try More Reference Here

In the etc directory under your Netbeans-Home, edit the file netbeans.conf file. -Xms and -Xmx should be increased to the values that allow your program to compile.

instructions in netbeans.conf :

# Note that default -Xmx and -XX:MaxPermSize are selected for you automatically.
# You can find these values in var/log/messages.log file in your userdir.
# The automatically selected value can be overridden by specifying -J-Xmx or
# -J-XX:MaxPermSize= here or on the command line.

Put the values in the netbeans_default_options string. Example :

netbeans_default_options="-J-client -J-Xss2m -J-Xms32m -J-XX:PermSize=32m -J-Dapple.laf.useScreenMenuBar=true -J-Dsun.java2d.noddraw=true -J-Dsun.java2d.dpiaware=true  -J-Dsun.awt.disableMixing=true -J-Dswing.aatext=true -J-Dawt.useSystemAAFontSettings=lcd --laf Nimbus"

What to do to speed up / free up memory windows:

  1. Disable Windows Update :

    • Open Task Manager, open tab Services, disable Windows Update:

disable win update

  1. Hit Ctrl + R and type Services.msc and press enter.
    • Sort by Startup Type
    • Select Services from 3rd party (non windows) which run Automatic, Right click, click Properties and change startup type to Manual


  • Sort by Status and Stop services from (3rd party) app you think unused

Convert XML to JSON (and back) using Javascript

The best way to do it using server side as client side doesn't work well in all scenarios. I was trying to build online json to xml and xml to json converter using javascript and I felt almost impossible as it was not working in all scenarios. Ultimately I ended up doing it server side using Newtonsoft in ASP.MVC. Here is the online converter

JDK was not found on the computer for NetBeans 6.5

I use the following steps to solve the problem:

First, Make sure

“Run this program in compatibality mode for: Windows XP (Service Pack 3)” and “Run this program as an administrator” are ENABLED.

Run in Command Prompt

C:\Users\{yourusernamehere}\Documents\Downloads\netbeans-6.5-ml-windows.exe –-javahome "C:\Program Files (x86)\Java\jdk1.6.0_18"

Changing specific text's color using NSMutableAttributedString in Swift

This extension works well when configuring the text of a label with an already set default color.

public extension String {
    func setColor(_ color: UIColor, ofSubstring substring: String) -> NSMutableAttributedString {
        let range = (self as NSString).range(of: substring)
        let attributedString = NSMutableAttributedString(string: self)
        attributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)
        return attributedString

For example

let text = "Hello World!"
let attributedText = text.setColor(.blue, ofSubstring: "World")

let myLabel = UILabel()
myLabel.textColor = .white
myLabel.attributedText = attributedText

How to get the indices list of all NaN value in numpy array?

Since x!=x returns the same boolean array with np.isnan(x) (because np.nan!=np.nan would return True), you could also write:


However, I still recommend writing np.argwhere(np.isnan(x)) since it is more readable. I just try to provide another way to write the code in this answer.

HashMaps and Null values?

Its a good programming practice to avoid having null values in a Map.

If you have an entry with null value, then it is not possible to tell whether an entry is present in the map or has a null value associated with it.

You can either define a constant for such cases (Example: String NOT_VALID = "#NA"), or you can have another collection storing keys which have null values.

Please check this link for more details.

Make content horizontally scroll inside a div

@marcio-junior's answer ( works perfectly, but I wanted to explain for those who don't understand why it works:

@a7omiton Along with @psyren89's response to your question

Think of the outer div as a movie screen and the inner div as the setting in which the characters move around. If you were viewing the setting in person, that is without a screen around it, you would be able to see all of the characters at once assuming your eyes have a large enough field of vision. That would mean the setting wouldn't have to scroll (move left to right) in order for you to see more of it and so it would stay still.

However, you are not at the setting in person, you are viewing it from your computer screen which has a width of 500px while the setting has a width of 1000px. Thus, you will need to scroll (move left to right) the setting in order to see more of the characters inside of it.

I hope that helps anyone who was lost on the principle.

Convert string with comma to integer

If someone is looking to sub out more than a comma I'm a fan of:


dunno about performance but, it is more flexible than a gsub, ie:


CSS to prevent child element from inheriting parent styles

Can't you style the forms themselves? Then, style the divs accordingly.

    /* styles */

You can always overrule inherited styles by making it important:

    /* styles */ !important

Count number of rows within each group

Create a new variable Count with a value of 1 for each row:

df1["Count"] <-1

Then aggregate dataframe, summing by the Count column:

df2 <- aggregate(df1[c("Count")], by=list(Year=df1$Year, Month=df1$Month), FUN=sum, na.rm=TRUE)

How to set IE11 Document mode to edge as default?

I was having the same problem while developing my own website. While it was resident locally, resources opened as file//. For pages from the internet, including my own loaded as http://, the F12 Developer did use Edge as default, but not while they were loaded into IE11 from local files.

After following the suggestions above, I unchecked the box for "Display intranet Sites in Compatibility View".

That did the trick without adding any extra coding to my web page, or adding a multitude of pages to populate the list. Now all local files open in Edge document mode with F12.

So if you are referring to using F12 for locally hosted files, this may help.

Why should C++ programmers minimize use of 'new'?

The reason why is complicated.

First, C++ is not garbage collected. Therefore, for every new, there must be a corresponding delete. If you fail to put this delete in, then you have a memory leak. Now, for a simple case like this:

std::string *someString = new std::string(...);
//Do stuff
delete someString;

This is simple. But what happens if "Do stuff" throws an exception? Oops: memory leak. What happens if "Do stuff" issues return early? Oops: memory leak.

And this is for the simplest case. If you happen to return that string to someone, now they have to delete it. And if they pass it as an argument, does the person receiving it need to delete it? When should they delete it?

Or, you can just do this:

std::string someString(...);
//Do stuff

No delete. The object was created on the "stack", and it will be destroyed once it goes out of scope. You can even return the object, thus transfering its contents to the calling function. You can pass the object to functions (typically as a reference or const-reference: void SomeFunc(std::string &iCanModifyThis, const std::string &iCantModifyThis). And so forth.

All without new and delete. There's no question of who owns the memory or who's responsible for deleting it. If you do:

std::string someString(...);
std::string otherString;
otherString = someString;

It is understood that otherString has a copy of the data of someString. It isn't a pointer; it is a separate object. They may happen to have the same contents, but you can change one without affecting the other:

someString += "More text.";
if(otherString == someString) { /*Will never get here */ }

See the idea?

How to compare strings in C conditional preprocessor-directives

[UPDATE: 2021.01.04]

One thing that has changed since I first posted this in 2014, is the format of #pragma message.

Nowadays, the parens are required!

#pragma message ("USER    IS " USER)
#pragma message ("USER_VS IS " USER_VS)

That said, the 2016 code (using characters, not strings) still works in VS2019.

But, as @Artyer points out, the version involving c_strcmp will NOT work in ANY modern compiler.

[UPDATE: 2018.05.03]

CAVEAT: Not all compilers implement the C++11 specification in the same way. The below code works in the compiler I tested on, while many commenters used a different compiler.

Quoting from Shafik Yaghmour's answer at: Computing length of a C string at compile time. Is this really a constexpr?

Constant expressions are not guaranteed to be evaluated at compile time, we only have a non-normative quote from draft C++ standard section 5.19 Constant expressions that says this though:

[...]>[ Note: Constant expressions can be evaluated during translation.—end note ]

That word can makes all the difference in the world.

So, YMMV on this (or any) answer involving constexpr, depending on the compiler writer's interpretation of the spec.

[UPDATED 2016.01.31]

As some didn't like my earlier answer because it avoided the whole compile time string compare aspect of the OP by accomplishing the goal with no need for string compares, here is a more detailed answer.

You can't! Not in C98 or C99. Not even in C11. No amount of MACRO manipulation will change this.

The definition of const-expression used in the #if does not allow strings.

It does allow characters, so if you limit yourself to characters you might use this:

#define JACK 'J'
#define QUEEN 'Q'

#define CHOICE JACK     // or QUEEN, your choice

#if 'J' == CHOICE
#define USER "jack"
#define USER_VS "queen"
#elif 'Q' == CHOICE
#define USER "queen"
#define USER_VS "jack"
#define USER "anonymous1"
#define USER_VS "anonymous2"

#pragma message "USER    IS " USER
#pragma message "USER_VS IS " USER_VS

You can! In C++11. If you define a compile time helper function for the comparison.

[2021.01.04: CAVEAT: This does not work in any MODERN compiler. See comment by @Artyer.]

// compares two strings in compile time constant fashion
constexpr int c_strcmp( char const* lhs, char const* rhs )
    return (('\0' == lhs[0]) && ('\0' == rhs[0])) ? 0
        :  (lhs[0] != rhs[0]) ? (lhs[0] - rhs[0])
        : c_strcmp( lhs+1, rhs+1 );
// some compilers may require ((int)lhs[0] - (int)rhs[0])

#define JACK "jack"
#define QUEEN "queen"

#define USER JACK       // or QUEEN, your choice

#if 0 == c_strcmp( USER, JACK )
#elif 0 == c_strcmp( USER, QUEEN )
#define USER_VS JACK
#define USER_VS "unknown"

#pragma message "USER    IS " USER
#pragma message "USER_VS IS " USER_VS

So, ultimately, you will have to change the way you accomlish your goal of choosing final string values for USER and USER_VS.

You can't do compile time string compares in C99, but you can do compile time choosing of strings.

If you really must do compile time sting comparisons, then you need to change to C++11 or newer variants that allow that feature.



#define jack_VS queen
#define queen_VS jack

#define USER jack          // jack    or queen, your choice
#define USER_VS USER##_VS  // jack_VS or queen_VS

// stringify usage: S(USER) or S(USER_VS) when you need the string form.
#define S(U) S_(U)
#define S_(U) #U

UPDATE: ANSI token pasting is sometimes less than obvious. ;-D

Putting a single # before a macro causes it to be changed into a string of its value, instead of its bare value.

Putting a double ## between two tokens causes them to be concatenated into a single token.

So, the macro USER_VS has the expansion jack_VS or queen_VS, depending on how you set USER.

The stringify macro S(...) uses macro indirection so the value of the named macro gets converted into a string. instead of the name of the macro.

Thus USER##_VS becomes jack_VS (or queen_VS), depending on how you set USER.

Later, when the stringify macro is used as S(USER_VS) the value of USER_VS (jack_VS in this example) is passed to the indirection step S_(jack_VS) which converts its value (queen) into a string "queen".

If you set USER to queen then the final result is the string "jack".

For token concatenation, see:

For token string conversion, see:

[UPDATED 2015.02.15 to correct a typo.]

How schedule build in Jenkins?

In the job configuration one can define various build triggers. With periodically build you can schedule the build by defining the date or day of the week and the time to execute the build.

The format is as follows:

MINUTE (0-59), HOUR (0-23), DAY (1-31), MONTH (1-12), DAY OF THE WEEK (0-6)

The letter H, representing the word Hash can be inserted instead of any of the values, it will calculate the parameter based on the hash code of your project name, this is so that if you are building several projects on your build machine at the same time, lets say midnight each day, they do not all start there build execution at the same time, each project starts its execution at a different minute depending on its hash code. You can also specify the value to be between numbers, i.e. H(0,30) will return the hash code of the project where the possible hashes are 0-30


start build daily at 08:30 in the morning, Monday - Friday:

  • 30 08 * * 1-5

weekday daily build twice a day, at lunchtime 12:00 and midnight 00:00, Sunday to Thursday:

  • 00 0,12 * * 0-4

start build daily in the late afternoon between 4:00 p.m. - 4:59 p.m. or 16:00 -16:59 depending on the projects hash:

  • H 16 * * 1-5

start build at midnight:

  • @midnight

or start build at midnight, every Saturday:

  • 59 23 * * 6

every first of every month between 2:00 a.m. - 02:30 a.m. :

  • H(0-30) 02 01 * *

more on CRON expressions

Difference between Running and Starting a Docker container

Explanation with an example:

Consider you have a game (iso) image in your computer.

When you run (mount your image as a virtual drive), a virtual drive is created with all the game contents in the virtual drive and the game installation file is automatically launched. [Running your docker image - creating a container and then starting it.]

But when you stop (similar to docker stop) it, the virtual drive still exists but stopping all the processes. [As the container exists till it is not deleted]

And when you do start (similar to docker start), from the virtual drive the games files start its execution. [starting the existing container]

In this example - The game image is your Docker image and virtual drive is your container.

How do ports work with IPv6?

They're the same, aren't they? Now I'm losing confidence in myself but I really thought IPv6 was just an addressing change. TCP and UDP are still addressed as they are under IPv4.

What's the default password of mariadb on fedora?

From :

In order to log into MariaDB to secure it, we'll need the current password for the root user. If you've just installed MariaDB, and you haven't set the root password yet, the password will be blank, so you should just press enter here.

the password will be blank

I think that's your answer.

User Control - Custom Properties

It is very simple, just add a property:

public string Value {
  get { return textBox1.Text; }
  set { textBox1.Text = value; }

Using the Text property is a bit trickier, the UserControl class intentionally hides it. You'll need to override the attributes to put it back in working order:

[Browsable(true), EditorBrowsable(EditorBrowsableState.Always), Bindable(true)]
public override string Text {
  get { return textBox1.Text; }
  set { textBox1.Text = value; }

Angular JS update input field after change

I wrote a directive you can use to bind an ng-model to any expression you want. Whenever the expression changes the model is set to the new value.

 module.directive('boundModel', function() {
      return {
        require: 'ngModel',
        link: function(scope, elem, attrs, ngModel) {
          var boundModel$watcher = scope.$watch(attrs.boundModel, function(newValue, oldValue) {
            if(newValue != oldValue) {

          // When $destroy is fired stop watching the change.
          // If you don't, and you come back on your state
          // you'll have two watcher watching the same properties
          scope.$on('$destroy', function() {

You can use it in your templates like this:

 <li>Total<input type="text" ng-model="total" bound-model="one * two"></li>      

AngularJS performs an OPTIONS HTTP request for a cross-origin resource

If you are using a nodeJS server, you can use this library, it worked fine for me

var express = require('express')
  , cors = require('cors')
  , app = express();


and after you can do an npm update.

How to call C++ function from C?

You will have to write a wrapper for C in C++ if you want to do this. C++ is backwards compatible, but C is not forwards compatible.

No input file specified

disabling PHP-FPM fixed my issue.

Placeholder in IE9

If you want to do it without using jquery or modenizer you can use the code below:


     "use strict";

     //shim for String's trim function..
     function trim(string){
         return string.trim ? string.trim() : string.replace(/^\s+|\s+$/g, "");

     //returns whether the given element has the given class name..
     function hasClassName(element, className){ 
         //refactoring of Prototype's function..
         var elClassName = element.className;
             return false;
         var regex = new RegExp("(^|\\s)" + className + "(\\s|$)");
         return regex.test(element.className);

     function removeClassName(element, className){
         //refactoring of Prototype's function..
         var elClassName = element.className;
         element.className = elClassName.replace(
             new RegExp("(^|\\s+)" + className + "(\\s+|$)"), ' ');

     function addClassName(element, className){
         var elClassName = element.className;
             element.className += " " + className;
             element.className = className;

     //strings to make event attachment x-browser.. 
     var addEvent = document.addEventListener ?
            'addEventListener' : 'attachEvent';
     var eventPrefix = document.addEventListener ? '' : 'on';

     //the class which is added when the placeholder is being used..
     var placeHolderClassName = 'usingPlaceHolder';

     //allows the given textField to use it's placeholder attribute
     //as if it's functionality is supported natively..
     window.placeHolder = function(textField){

         //don't do anything if you get it for free..
         if('placeholder' in document.createElement('input'))

         //don't do anything if the place holder attribute is not
         //defined or is blank..
         var placeHolder = textField.getAttribute('placeholder');        

         //if it's just the empty string do nothing..
         placeHolder = trim(placeHolder);
         if(placeHolder === '')

         //called on blur - sets the value to the place holder if it's empty..
         var onBlur = function(){
             if(textField.value !== '') //a space is a valid input..
             textField.value = placeHolder;
             addClassName(textField, placeHolderClassName);

         //the blur event..
         textField[addEvent](eventPrefix + 'blur', onBlur, false);

         //the focus event - removes the place holder if required..
         textField[addEvent](eventPrefix + 'focus', function(){
             if(hasClassName(textField, placeHolderClassName)){
                removeClassName(textField, placeHolderClassName);
                textField.value = "";
         }, false);

         //the submit event on the form to which it's associated - if the
         //placeholder is attached set the value to be empty..
         var form = textField.form;
             form[addEvent](eventPrefix + 'submit', function(){
                 if(hasClassName(textField, placeHolderClassName))
                     textField.value = '';
            }, false);

         onBlur(); //call the onBlur to set it initially..


For each text field you want to use it for you need to run placeHolder(HTMLInputElement), but I guess you can just change that to suit! Also, doing it this way, rather than just on load means that you can make it work for inputs which aren't in the DOM when the page loads.

Note, that this works by applying the class: usingPlaceHolder to the input element, so you can use this to style it (e.g. add the rule .usingPlaceHolder { color: #999; font-style: italic; } to make it look better).

How to change facebook login button with my custom image

Found a site on google explaining some changes, according to the author of the page fb does not allow custom buttons. Heres the website.

Unfortunately, it’s against Facebook’s developer policies, which state:

You must not circumvent our intended limitations on core Facebook features.

The Facebook Connect button is intended to be rendered in FBML, which means it’s only meant to look the way Facebook lets it.

Angular - "has no exported member 'Observable'"

The angular-split component is not supported in Angular 6, so to make it compatible with Angular 6 install following dependency in your application

To get this working until it's updated use:

"dependencies": {
"angular-split": "1.0.0-rc.3",
"rxjs": "^6.2.2",
    "rxjs-compat": "^6.2.2",

Simple way to sort strings in the (case sensitive) alphabetical order

The simple way to solve the problem is to use ComparisonChain from Guava

private static Comparator<String> stringAlphabeticalComparator = new Comparator<String>() {
        public int compare(String str1, String str2) {
            return ComparisonChain.start().
                                compare(str1,str2, String.CASE_INSENSITIVE_ORDER).
Collections.sort(list, stringAlphabeticalComparator);

The first comparator from the chain will sort strings according to the case insensitive order, and the second comparator will sort strings according to the case insensitive order. As excepted strings appear in the result according to the alphabetical order:


ServletContext.getRequestDispatcher() vs ServletRequest.getRequestDispatcher()

request.getRequestDispatcher(“url”) means the dispatch is relative to the current HTTP request.Means this is for chaining two servlets with in the same web application Example

RequestDispatcher reqDispObj = request.getRequestDispatcher("/home.jsp");

getServletContext().getRequestDispatcher(“url”) means the dispatch is relative to the root of the ServletContext.Means this is for chaining two web applications with in the same server/two different servers


RequestDispatcher reqDispObj = getServletContext().getRequestDispatcher("/ContextRoot/home.jsp");

Add a column to existing table and uniquely number them on MS SQL Server

And the Postgres equivalent (second line is mandatory only if you want "id" to be a key):


Import Python Script Into Another?

Following worked for me and it seems very simple as well:

Let's assume that we want to import a script ./data/ and want to access get_set1() function in it.

import sys
sys.path.insert(0, './data/')
import get_my_file as db

print (db.get_set1())

XPath: difference between dot and text()

There is a difference between . and text(), but this difference might not surface because of your input document.

If your input document looked like (the simplest document one can imagine given your XPath expressions)

Example 1

  <a>Ask Question</a>

Then //a[text()="Ask Question"] and //a[.="Ask Question"] indeed return exactly the same result. But consider a different input document that looks like

Example 2

  <a>Ask Question<other/>

where the a element also has a child element other that follows immediately after "Ask Question". Given this second input document, //a[text()="Ask Question"] still returns the a element, while //a[.="Ask Question"] does not return anything!

This is because the meaning of the two predicates (everything between [ and ]) is different. [text()="Ask Question"] actually means: return true if any of the text nodes of an element contains exactly the text "Ask Question". On the other hand, [.="Ask Question"] means: return true if the string value of an element is identical to "Ask Question".

In the XPath model, text inside XML elements can be partitioned into a number of text nodes if other elements interfere with the text, as in Example 2 above. There, the other element is between "Ask Question" and a newline character that also counts as text content.

To make an even clearer example, consider as an input document:

Example 3

<a>Ask Question<other/>more text</a>

Here, the a element actually contains two text nodes, "Ask Question" and "more text", since both are direct children of a. You can test this by running //a/text() on this document, which will return (individual results separated by ----):

Ask Question
more text

So, in such a scenario, text() returns a set of individual nodes, while . in a predicate evaluates to the string concatenation of all text nodes. Again, you can test this claim with the path expression //a[.='Ask Questionmore text'] which will successfully return the a element.

Finally, keep in mind that some XPath functions can only take one single string as an input. As LarsH has pointed out in the comments, if such an XPath function (e.g. contains()) is given a sequence of nodes, it will only process the first node and silently ignore the rest.

JQuery Find #ID, RemoveClass and AddClass

corrected Code:


Extension mysqli is missing, phpmyadmin doesn't work

Just add this line to your php.ini if you are using XAMPP etc. also check if it is already there just remove ; from front of it

extension= php_mysqli.dll

and stop and start apache and MySQL it will work.

How do I install a custom font on an HTML site

You can use @font-face in most modern browsers.

Here's some articles on how it works:

Here is a good syntax for adding the font to your app:

Here are a couple of places to convert fonts for use with @font-face:

Also cufon will work if you don't want to use font-face, and it has good documentation on the web site:

Oracle: how to UPSERT (update or insert into a table?)

None of the answers given so far is safe in the face of concurrent accesses, as pointed out in Tim Sylvester's comment, and will raise exceptions in case of races. To fix that, the insert/update combo must be wrapped in some kind of loop statement, so that in case of an exception the whole thing is retried.

As an example, here's how Grommit's code can be wrapped in a loop to make it safe when run concurrently:

) IS
    MERGE INTO Employee USING dual ON ( "id"=2097153 )
      WHEN MATCHED THEN UPDATE SET "last"="smith" , "name"="john"
      WHEN NOT MATCHED THEN INSERT ("id","last","name") 
        VALUES ( 2097153,"smith", "john" );
    EXIT; -- success? -> exit loop
    WHEN NO_DATA_FOUND THEN -- the entry was concurrently deleted
      NULL; -- exception? -> no op, i.e. continue looping
    WHEN DUP_VAL_ON_INDEX THEN -- an entry was concurrently inserted
      NULL; -- exception? -> no op, i.e. continue looping

N.B. In transaction mode SERIALIZABLE, which I don't recommend btw, you might run into ORA-08177: can't serialize access for this transaction exceptions instead.

Warning: mysqli_connect(): (HY000/1045): Access denied for user 'username'@'localhost' (using password: YES)

Make sure that your password doesn't have special characters and just keep a plain password (for ex: 12345), it will work. This is the strangest thing that I have ever seen. I spent about 2 hours to figure this out.

Note: 12345 mentioned below is your plain password

GRANT ALL PRIVILEGES ON dbname.* TO 'yourusername'@'%' IDENTIFIED BY '12345';

Call JavaScript function on DropDownList SelectedIndexChanged Event:

You can use the ScriptManager.RegisterStartupScript(); to call any of your javascript event/Client Event from the server. For example, to display a message using javascript's alert();, you can do this:

protected void ddl_SelectedIndexChanged(object sender, EventArgs e)
Response.write("<script>alert('This is my message');</script>");
 //----or alternatively and to be more proper
 ScriptManager.RegisterStartupScript(this, this.GetType(), "callJSFunction", "alert('This is my message')", true);

To be exact for you, do this...

protected void ddl_SelectedIndexChanged(object sender, EventArgs e)
 ScriptManager.RegisterStartupScript(this, this.GetType(), "callJSFunction", "CalcTotalAmt();", true);

MySQL & Java - Get id of the last inserted value (JDBC)

Wouldn't you just change:

numero = stmt.executeUpdate(query);


numero = stmt.executeUpdate(query, Statement.RETURN_GENERATED_KEYS);

Take a look at the documentation for the JDBC Statement interface.

Update: Apparently there is a lot of confusion about this answer, but my guess is that the people that are confused are not reading it in the context of the question that was asked. If you take the code that the OP provided in his question and replace the single line (line 6) that I am suggesting, everything will work. The numero variable is completely irrelevant and its value is never read after it is set.

Copying the cell value preserving the formatting from one cell to another in excel using VBA

I prefer to avoid using select

     With sheets("sheetname").range("I10") 
          .PasteSpecial Paste:=xlPasteValues, _
                  Operation:=xlNone, _
                  SkipBlanks:=False, _
          .PasteSpecial Paste:=xlPasteFormats, _
                  Operation:=xlNone, _
                  SkipBlanks:=False, _
          .font.color = sheets("sheetname").range("F10").font.color
      End With

How to convert a List<String> into a comma separated string without iterating List explicitly

With Java 8:

String csv = String.join(",", ids);

With Java 7-, there is a dirty way (note: it works only if you don't insert strings which contain ", " in your list) - obviously, List#toString will perform a loop to create idList but it does not appear in your code:

List<String> ids = new ArrayList<String>();
String idList = ids.toString();
String csv = idList.substring(1, idList.length() - 1).replace(", ", ",");

How do you create an asynchronous HTTP request in JAVA?

Here is a solution using apache HttpClient and making the call in a separate thread. This solution is useful if you are only making one async call. If you are making multiple calls I suggest using apache HttpAsyncClient and placing the calls in a thread pool.

import java.lang.Thread;

import org.apache.hc.client5.http.classic.methods.HttpGet;
import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
import org.apache.hc.client5.http.impl.classic.HttpClients;

public class ApacheHttpClientExample {
    public static void main(final String[] args) throws Exception {
        try (final CloseableHttpClient httpclient = HttpClients.createDefault()) {
            final HttpGet httpget = new HttpGet("");
            new Thread(() -> {
                 final String responseBody = httpclient.execute(httpget);

How do I increment a DOS variable in a FOR /F loop?

The problem with your code snippet is the way variables are expanded. Variable expansion is usually done when a statement is first read. In your case the whole FOR loop and its block is read and all variables, except the loop variables are expanded to their current value.

This means %c% in your echo %%i, %c% expanded instantly and so is actually used as echo %%i, 1 in each loop iteration.

So what you need is the delayed variable expansion. Find some good explanation about it here.

Variables that should be delay expanded are referenced with !VARIABLE! instead of %VARIABLE%. But you need to activate this feature with setlocal ENABLEDELAYEDEXPANSION and reset it with a matching endlocal.

Your modified code would look something like that:

set TEXT_T="myfile.txt"

set /a c=1


FOR /F "tokens=1 usebackq" %%i in (%TEXT_T%) do (
  set /a c=c+1

  echo %%i, !c!


WebForms UnobtrusiveValidationMode requires a ScriptResourceMapping for 'jquery'. Please add a ScriptResourceMapping named jquery(case-sensitive)

Rather than disabling a new feature, I opted to follow the instructions of the error. In my global.asax.cs I added:

protected void Application_Start(object sender, EventArgs e)
    string JQueryVer = "1.7.1";
    ScriptManager.ScriptResourceMapping.AddDefinition("jquery", new ScriptResourceDefinition
        Path = "~/Scripts/jquery-" + JQueryVer + ".min.js",
        DebugPath = "~/Scripts/jquery-" + JQueryVer + ".js",
        CdnPath = "" + JQueryVer + ".min.js",
        CdnDebugPath = "" + JQueryVer + ".js",
        CdnSupportsSecureConnection = true,
        LoadSuccessExpression = "window.jQuery"

This comes from an msdn blog post which highlights some of the advantages of script resource mappings. Of particular interest to me was centralized control over the delivery of the script files based on "debug=true", EnableCDN, etc.

What are the differences in die() and exit() in PHP?

From what I know when I look at this question here

It said there that "in PHP, there is a distinct difference in Header output. In the examples below I chose to use a different header but for sake of showing the difference between exit() and die() that doesn't matter", and tested (personally)

sub and gsub function?

That won't work if the string contains more than one match... try this:

echo "/x/y/z/x" | awk '{ gsub("/", "_") ; system( "echo "  $0) }'

or better (if the echo isn't a placeholder for something else):

echo "/x/y/z/x" | awk '{ gsub("/", "_") ; print $0 }'

In your case you want to make a copy of the value before changing it:

echo "/x/y/z/x" | awk '{ c=$0; gsub("/", "_", c) ; system( "echo " $0 " " c )}'

What's the difference between 'r+' and 'a+' when open file in python?

Python opens files almost in the same way as in C:

  • r+ Open for reading and writing. The stream is positioned at the beginning of the file.

  • a+ Open for reading and appending (writing at end of file). The file is created if it does not exist. The initial file position for reading is at the beginning of the file, but output is appended to the end of the file (but in some Unix systems regardless of the current seek position).

How to convert integer into date object python?

Here is what I believe answers the question (Python 3, with type hints):

from datetime import date

def int2date(argdate: int) -> date:
    If you have date as an integer, use this method to obtain a object.

    argdate : int
      Date as a regular integer value (example: 20160618)

      A date object which corresponds to the given value `argdate`.
    year = int(argdate / 10000)
    month = int((argdate % 10000) / 100)
    day = int(argdate % 100)

    return date(year, month, day)


The code above produces the expected 2016-06-18.

SQL Developer is returning only the date, not the time. How do I fix this?

Well I found this way :

Oracle SQL Developer (Left top icon) > Preferences > Database > NLS and set the Date Format as MM/DD/YYYY HH24:MI:SS

enter image description here

How do I write a bash script to restart a process if it dies?

The easiest way to do it is using flock on file. In Python script you'd do

lf = open('/tmp/script.lock','w')
if(fcntl.flock(lf, fcntl.LOCK_EX|fcntl.LOCK_NB) != 0): 
   sys.exit('other instance already running')

In shell you can actually test if it's running:

if [ `flock -xn /tmp/script.lock -c 'echo 1'` ]; then 
   echo 'it's not running'
   echo -n 'it's already running with PID '
   cat /tmp/script.lock

But of course you don't have to test, because if it's already running and you restart it, it'll exit with 'other instance already running'

When process dies, all it's file descriptors are closed and all locks are automatically removed.

Compiler error: "initializer element is not a compile-time constant"

The reason is that your are defining your imageSegment outside of a function in your source code (static variable).

In such cases, the initialization cannot include execution of code, like calling a function or allocation a class. Initializer must be a constant whose value is known at compile time.

You can then initialize your static variable inside of your init method (if you postpone its declaration to init).

Command to list all files in a folder as well as sub-folders in windows

If you simply need to get the basic snapshot of the files + folders. Follow these baby steps:

  • Press Windows + R
  • Press Enter
  • Type cmd
  • Press Enter
  • Type dir -s
  • Press Enter

How to loop through file names returned by find?

based on other answers and comment of @phk, using fd #3:
(which still allows to use stdin inside the loop)

while IFS= read -r f <&3; do
    echo "$f"

done 3< <(find . -iname "*filename*")

Defining a HTML template to append using JQuery

In order to solve this problem, I recognize two solutions:

  • The first one goes with AJAX, with which you'll have to load the template from another file and just add everytime you want with .clone().

    $.get('url/to/template', function(data) {
        temp = data
        $('.search').keyup(function() {
            $.each(items, function(index) {

    Take into account that the event should be added once the ajax has completed to be sure the data is available!

  • The second one would be to directly add it anywhere in the original html, select it and hide it in jQuery:

    temp = $('.list_group_item').hide()

    You can after add a new instance of the template with

    $('.search').keyup(function() {
        $.each(items, function(index) {
  • Same as the previous one, but if you don't want the template to remain there, but just in the javascript, I think you can use (have not tested it!) .detach() instead of hide.

    temp = $('.list_group_item').detach()

    .detach() removes elements from the DOM while keeping the data and events alive (.remove() does not!).

HRESULT: 0x800A03EC on Worksheet.range

Simply, the excel file is corrupt. Best solution is change/repair the file.(make a copy of the existing file and rename it)

How to install JQ on Mac by command-line?

For CentOS, RHEL, Amazon Linux: sudo yum install jq

Scroll to a div using jquery

Add this little function and use it as so: $('div').scrollTo(500);

  scrollTo : function(speed, easing)
    return this.each(function()
      var targetOffset = $(this).offset().top;
      $('html,body').animate({scrollTop: targetOffset}, speed, easing);

Display two fields side by side in a Bootstrap Form

@KyleMit's answer on Bootstrap 4 has changed a little

<div class="input-group">
    <input type="text" class="form-control">
    <div class="input-group-prepend">
        <span class="input-group-text">-</span>
    <input type="text" class="form-control">

Way to insert text having ' (apostrophe) into a SQL table

insert into table1 values("sunil''s book",123,99382932938);

use double apostrophe inside of single apostrophe, it will work

How to set the part of the text view is clickable

This is my MovementMethod for detecting link/text/image clicks. It is modified LinkMovementMethod.

import android.text.Layout;
import android.text.NoCopySpan;
import android.text.Selection;
import android.text.Spannable;
import android.text.method.ScrollingMovementMethod;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.widget.TextView;

public class ClickMovementMethod extends ScrollingMovementMethod {
private Object FROM_BELOW = new NoCopySpan.Concrete();

private static final int CLICK = 1;
private static final int UP = 2;
private static final int DOWN = 3;

private Listener listener;

public void setListener(Listener listener) {
    this.listener = listener;

public boolean canSelectArbitrarily() {
    return true;

protected boolean handleMovementKey(TextView widget, Spannable buffer, int keyCode,
                                    int movementMetaState, KeyEvent event) {
    switch (keyCode) {
        case KeyEvent.KEYCODE_DPAD_CENTER:
        case KeyEvent.KEYCODE_ENTER:
            if (KeyEvent.metaStateHasNoModifiers(movementMetaState)) {
                if (event.getAction() == KeyEvent.ACTION_DOWN &&
                        event.getRepeatCount() == 0 && action(CLICK, widget, buffer)) {
                    return true;
    return super.handleMovementKey(widget, buffer, keyCode, movementMetaState, event);

protected boolean up(TextView widget, Spannable buffer) {
    if (action(UP, widget, buffer)) {
        return true;

    return super.up(widget, buffer);

protected boolean down(TextView widget, Spannable buffer) {
    if (action(DOWN, widget, buffer)) {
        return true;

    return super.down(widget, buffer);

protected boolean left(TextView widget, Spannable buffer) {
    if (action(UP, widget, buffer)) {
        return true;

    return super.left(widget, buffer);

protected boolean right(TextView widget, Spannable buffer) {
    if (action(DOWN, widget, buffer)) {
        return true;

    return super.right(widget, buffer);

private boolean action(int what, TextView widget, Spannable buffer) {
    Layout layout = widget.getLayout();

    int padding = widget.getTotalPaddingTop() +
    int areatop = widget.getScrollY();
    int areabot = areatop + widget.getHeight() - padding;

    int linetop = layout.getLineForVertical(areatop);
    int linebot = layout.getLineForVertical(areabot);

    int first = layout.getLineStart(linetop);
    int last = layout.getLineEnd(linebot);

    ClickableSpan[] candidates = buffer.getSpans(first, last, URLSpan.class);

    int a = Selection.getSelectionStart(buffer);
    int b = Selection.getSelectionEnd(buffer);

    int selStart = Math.min(a, b);
    int selEnd = Math.max(a, b);

    if (selStart < 0) {
        if (buffer.getSpanStart(FROM_BELOW) >= 0) {
            selStart = selEnd = buffer.length();

    if (selStart > last)
        selStart = selEnd = Integer.MAX_VALUE;
    if (selEnd < first)
        selStart = selEnd = -1;

    switch (what) {
        case CLICK:
            if (selStart == selEnd) {
                return false;

            if (listener != null) {
                URLSpan[] link = buffer.getSpans(selStart, selEnd, URLSpan.class);
                if (link.length >= 1) {
                } else {
                    ImageSpan[] image = buffer.getSpans(selStart, selEnd, ImageSpan.class);
                    if (image.length >= 1) {
                    } else {

        case UP:
            int beststart, bestend;

            beststart = -1;
            bestend = -1;

            for (int i = 0; i < candidates.length; i++) {
                int end = buffer.getSpanEnd(candidates[i]);

                if (end < selEnd || selStart == selEnd) {
                    if (end > bestend) {
                        beststart = buffer.getSpanStart(candidates[i]);
                        bestend = end;

            if (beststart >= 0) {
                Selection.setSelection(buffer, bestend, beststart);
                return true;


        case DOWN:
            beststart = Integer.MAX_VALUE;
            bestend = Integer.MAX_VALUE;

            for (int i = 0; i < candidates.length; i++) {
                int start = buffer.getSpanStart(candidates[i]);

                if (start > selStart || selStart == selEnd) {
                    if (start < beststart) {
                        beststart = start;
                        bestend = buffer.getSpanEnd(candidates[i]);

            if (bestend < Integer.MAX_VALUE) {
                Selection.setSelection(buffer, beststart, bestend);
                return true;


    return false;

public boolean onTouchEvent(TextView widget, Spannable buffer,
                            MotionEvent event) {
    int action = event.getAction();

    if (action == MotionEvent.ACTION_UP ||
            action == MotionEvent.ACTION_DOWN) {
        int x = (int) event.getX();
        int y = (int) event.getY();

        x -= widget.getTotalPaddingLeft();
        y -= widget.getTotalPaddingTop();

        x += widget.getScrollX();
        y += widget.getScrollY();

        Layout layout = widget.getLayout();
        int line = layout.getLineForVertical(y);
        int off = layout.getOffsetForHorizontal(line, x);

        URLSpan[] link = buffer.getSpans(off, off, URLSpan.class);

        if (action == MotionEvent.ACTION_UP) {
            if (listener != null) {
                if (link.length >= 1) {
                } else {
                    ImageSpan[] image = buffer.getSpans(off, off, ImageSpan.class);
                    if (image.length >= 1) {
                    } else if (Selection.getSelectionStart(buffer) == Selection.getSelectionEnd(buffer)) {

        if (action == MotionEvent.ACTION_DOWN && link.length != 0) {
            return true;

        if (link.length == 0) {

    return super.onTouchEvent(widget, buffer, event);

public void initialize(TextView widget, Spannable text) {

public void onTakeFocus(TextView view, Spannable text, int dir) {

    if ((dir & View.FOCUS_BACKWARD) != 0) {
        text.setSpan(FROM_BELOW, 0, 0, Spannable.SPAN_POINT_POINT);
    } else {

public interface Listener {

    void onClick(String clicked);

    void onTextClicked();

    void onImageClicked(String source);



Is there a foreach loop in Go?

A "for" statement with a "range" clause iterates through all entries of an array, slice, string or map, or values received on a channel. For each entry it assigns iteration values to corresponding iteration variables and then executes the block.

As an example:

for index, element := range someSlice {
    // index is the index where we are
    // element is the element from someSlice for where we are

If you don't care about the index, you can use _:

for _, element := range someSlice {
    // element is the element from someSlice for where we are

The underscore, _, is the blank identifier, an anonymous placeholder.

Jenkins pipeline if else not working

It requires a bit of rearranging, but when does a good job to replace conditionals above. Here's the example from above written using the declarative syntax. Note that test3 stage is now two different stages. One that runs on the master branch and one that runs on anything else.

stage ('Test 3: Master') {
    when { branch 'master' }
    steps { 
        echo 'I only execute on the master branch.' 

stage ('Test 3: Dev') {
    when { not { branch 'master' } }
    steps {
        echo 'I execute on non-master branches.'

HTML form submit to PHP script

<form method="POST" action="chk_kw.php">
    <select name="website_string"> 
        <option selected="selected"></option>
        <option value="abc">abc</option>
        <option value="def">def</option>
        <option value="hij">hij</option>   
    <input type="submit">

  • As your form gets more complex, you can a quick check at top of your php script using print_r($_POST);, it'll show what's being submitted an the respective element name.
  • To get the submitted value of the element in question do:

    $website_string = $_POST['website_string'];

Apache 2.4.6 on Ubuntu Server: Client denied by server configuration (PHP FPM) [While loading PHP file]

For those of you on AWS (Amazon Web Services), remember to add a rule for your SSL port (in my case 443) to your security groups. I was getting this error because I forgot to open the port.

3 hours of tearing my hair out later...

What is the meaning of # in URL and how can I use that?

Originally it was used as an anchor to jump to an element with the same name/id.

However, nowadays it's usually used with AJAX-based pages since changing the hash can be detected using JavaScript and allows you to use the back/forward button without actually triggering a full page reload.

How to strip comma in Python string

You want to replace it, not strip it:

s = s.replace(',', '')

Circle line-segment collision detection algorithm?

I have created this function for iOS following the answer given by chmike

+ (NSArray *)intersectionPointsOfCircleWithCenter:(CGPoint)center withRadius:(float)radius toLinePoint1:(CGPoint)p1 andLinePoint2:(CGPoint)p2
    NSMutableArray *intersectionPoints = [NSMutableArray array];

    float Ax = p1.x;
    float Ay = p1.y;
    float Bx = p2.x;
    float By = p2.y;
    float Cx = center.x;
    float Cy = center.y;
    float R = radius;

    // compute the euclidean distance between A and B
    float LAB = sqrt( pow(Bx-Ax, 2)+pow(By-Ay, 2) );

    // compute the direction vector D from A to B
    float Dx = (Bx-Ax)/LAB;
    float Dy = (By-Ay)/LAB;

    // Now the line equation is x = Dx*t + Ax, y = Dy*t + Ay with 0 <= t <= 1.

    // compute the value t of the closest point to the circle center (Cx, Cy)
    float t = Dx*(Cx-Ax) + Dy*(Cy-Ay);

    // This is the projection of C on the line from A to B.

    // compute the coordinates of the point E on line and closest to C
    float Ex = t*Dx+Ax;
    float Ey = t*Dy+Ay;

    // compute the euclidean distance from E to C
    float LEC = sqrt( pow(Ex-Cx, 2)+ pow(Ey-Cy, 2) );

    // test if the line intersects the circle
    if( LEC < R )
        // compute distance from t to circle intersection point
        float dt = sqrt( pow(R, 2) - pow(LEC,2) );

        // compute first intersection point
        float Fx = (t-dt)*Dx + Ax;
        float Fy = (t-dt)*Dy + Ay;

        // compute second intersection point
        float Gx = (t+dt)*Dx + Ax;
        float Gy = (t+dt)*Dy + Ay;

        [intersectionPoints addObject:[NSValue valueWithCGPoint:CGPointMake(Fx, Fy)]];
        [intersectionPoints addObject:[NSValue valueWithCGPoint:CGPointMake(Gx, Gy)]];

    // else test if the line is tangent to circle
    else if( LEC == R ) {
        // tangent point to circle is E
        [intersectionPoints addObject:[NSValue valueWithCGPoint:CGPointMake(Ex, Ey)]];
    else {
        // line doesn't touch circle

    return intersectionPoints;

Watermark / hint text / placeholder TextBox

This library has a watermark.

Nuget package

Sample usage:

<TextBox adorners:Watermark.Text="Write something here" 
         adorners:Watermark.TextStyle="{StaticResource AdornerTextStyle}"

Remove scrollbars from textarea

Hide scroll bar, but while still being able to scroll using CSS

To hide the scrollbar use -webkit- because it is supported by major browsers (Google Chrome, Safari or newer versions of Opera). There are many other options for the other browsers which are listed below:

    -webkit- (Chrome, Safari, newer versions of Opera):
    .element::-webkit-scrollbar { width: 0 !important }
    -moz- (Firefox):
    .element { overflow: -moz-scrollbars-none; }
    -ms- (Internet Explorer +10):
    .element { -ms-overflow-style: none; }


Is JavaScript object-oriented?

Objects in JavaScript inherit directly from objects. What can be more object oriented?

Calculate last day of month in JavaScript

var month = 0; // January
var d = new Date(2008, month + 1, 0);
alert(d); // last day in January

IE 6:                     Thu Jan 31 00:00:00 CST 2008
IE 7:                     Thu Jan 31 00:00:00 CST 2008
IE 8: Beta 2:             Thu Jan 31 00:00:00 CST 2008
Opera 8.54:               Thu, 31 Jan 2008 00:00:00 GMT-0600
Opera 9.27:               Thu, 31 Jan 2008 00:00:00 GMT-0600
Opera 9.60:               Thu Jan 31 2008 00:00:00 GMT-0600
Firefox         Thu Jan 31 2008 00:00:00 GMT-0600 (Canada Central Standard Time)
Firefox 3.0.3:            Thu Jan 31 2008 00:00:00 GMT-0600 (Canada Central Standard Time)
Google Chrome Thu Jan 31 2008 00:00:00 GMT-0600 (Canada Central Standard Time)
Safari for Windows 3.1.2: Thu Jan 31 2008 00:00:00 GMT-0600 (Canada Central Standard Time)

Output differences are due to differences in the toString() implementation, not because the dates are different.

Of course, just because the browsers identified above use 0 as the last day of the previous month does not mean they will continue to do so, or that browsers not listed will do so, but it lends credibility to the belief that it should work the same way in every browser.

How to pass in parameters when use resource service?

I suggest you to use provider. Provide is good when you want to configure it first before to use (against Service/Factory)

Something like:

.provider('Magazines', function() {

    this.url = '/';
    this.urlArray = '/';
    this.organId = 'Default';

    this.$get = function() {
        var url = this.url;
        var urlArray = this.urlArray;
        var organId = this.organId;

        return {
            invoke: function() {
                return ......

    this.setUrl  = function(url) {
        this.url = url;

   this.setUrlArray  = function(urlArray) {
        this.urlArray = urlArray;

    this.setOrganId  = function(organId) {
        this.organId = organId;


And now controller:

function MyCtrl($scope, Magazines) {        




Return different type of data from a method in java?

you can have the return as an object. You create that object 'on fly' in your

function: if(int) 
 return new object(){
   int nr=..

same for string. But I am concerned that is an expensive solution...

Python pip install fails: invalid command egg_info

I just convert liquidki's answer into Ubuntu commands. On an Ubuntu based system it works!:

sudo apt -y install python-pip
pip install -U pip
sudo pip install -U setuptools

Replace only text inside a div using jquery

If you actually know the text you are going to replace you could use

$('#one').contents(':contains("Hi I am text")')[0].nodeValue = '"Hi I am replace"';


$('#one').contents(':not(*)')[1].nodeValue = '"Hi I am replace"';

$('#one').contents(':not(*)') selects non-element child nodes in this case text nodes and the second node is the one we want to replace.

Counting number of characters in a file through shell script

awk only

awk 'BEGIN{FS=""}{for(i=1;i<=NF;i++)c++}END{print "total chars:"c}' file

shell only

echo ${#var}


ruby -0777 -ne 'print $_.size' file

"unadd" a file to svn before commit

Full process (Unix svn package):

Check files are not in SVN:

> svn st -u folder 
? folder

Add all (including ignored files):

> svn add folder
A   folder
A   folder/file1.txt
A   folder/folder2
A   folder/folder2/file2.txt
A   folder/folderToIgnore
A   folder/folderToIgnore/fileToIgnore1.txt
A   fileToIgnore2.txt

Remove "Add" Flag to All * Ignore * files:

> cd folder

> svn revert --recursive folderToIgnore
Reverted 'folderToIgnore'
Reverted 'folderToIgnore/fileToIgnore1.txt'

> svn revert fileToIgnore2.txt
Reverted 'fileToIgnore2.txt'

Edit svn ignore on folder

svn propedit svn:ignore .

Add two singles lines with just the following:


Check which files will be upload and commit:

> cd ..

> svn st -u
A   folder
A   folder/file1.txt
A   folder/folder2
A   folder/folder2/file2.txt

> svn ci -m "Commit message here"

Check If array is null or not in php

you can use


to check if the main array is empty or not.

But since you have a SimpleXMLElement object, you need to query the object if it is empty or not. See


if (empty($result) || !isset($result['Tags'])) {
    return false;
if ( !($result['Tags'] instanceof SimpleXMLElement)) {
    return false;
return ($result['Tags']->count());

anaconda - path environment variable in windows

To export the exact set of paths used by Anaconda, use the command echo %PATH% in Anaconda Prompt. This is needed to avoid problems with certain libraries such as SSL.


How to convert Blob to File in JavaScript

Joshua P Nixon's answer is correct but I had to set last modified date also. so here is the code.

var file = new File([blob], "file_name", {lastModified: 1534584790000});

1534584790000 is an unix timestamp for "GMT: Saturday, August 18, 2018 9:33:10 AM"

How to loop through elements of forms with JavaScript?

You can use getElementsByTagName function, it returns a HTMLCollection of elements with the given tag name.

var elements = document.getElementsByTagName("input")
for (var i = 0; i < elements.length; i++) {
    if(elements[i].value == "") {
        //Do something here


You can also use document.myform.getElementsByTagName provided you have given a name to yoy form

DEMO with form Name

Git command to show which specific files are ignored by .gitignore

Another option that's pretty clean (No pun intended.):

git clean -ndX


$ git help clean

git-clean - Remove untracked files from the working tree
-n, --dry-run - Don't actually remove anything, just show what would be done.
-d - Remove untracked directories in addition to untracked files.
-X - Remove only files ignored by Git.

Note: This solution will not show ignored files that have already been removed.

Don't reload application when orientation changes

You just have to go to the AndroidManifest.xml and inside or in your activities labels, you have to type this line of code as someone up there said:


So, you'll have something like this:

<activity android:name="ActivityMenu"

Hope it works!

Differences between "java -cp" and "java -jar"?

With the -cp argument you provide the classpath i.e. path(s) to additional classes or libraries that your program may require when being compiled or run. With -jar you specify the executable JAR file that you want to run.

You can't specify them both. If you try to run java -cp folder/myexternallibrary.jar -jar myprogram.jar then it won't really work. The classpath for that JAR should be specified in its Manifest, not as a -cp argument.

You can find more about this here and here.

PS: -cp and -classpath are synonyms.