HTML table with horizontal scrolling (first column fixed)

Take a look at this JQuery plugin:

It adds vertical (fixed header row) or horizontal (fixed first column) scrolling to an existing HTML table. There is a demo you can check for both cases of scrolling.

parent & child with position fixed, parent overflow:hidden bug

Because a fixed position element is fixed with respect to the viewport, not another element. Therefore since the viewport isn't cutting it off, the overflow becomes irrelevant.

Whereas the position and dimensions of an element with position:absolute are relative to its containing block, the position and dimensions of an element with position:fixed are always relative to the initial containing block. This is normally the viewport: the browser window or the paper’s page box.

ref: http://www.w3.org/wiki/CSS_absolute_and_fixed_positioning#Fixed_positioning

Fixed position but relative to container

Check this:

<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title></title>
    </head>
    <body style="width: 1000px !important;margin-left: auto;margin-right: auto">
        <div style="width: 100px; height: 100px; background-color: #ccc; position:fixed;">
        </div>
        <div id="1" style="width: 100%; height: 600px; background-color: #800000">
        </div>
        <div id="2" style="width: 100%; height: 600px; background-color: #100000">
        </div>
        <div id="3" style="width: 100%; height: 600px; background-color: #400000">
        </div>
    </body>
</html>

Fixed header table with horizontal scrollbar and vertical scrollbar on

you can use following CSS code..

body {
    margin:0;
    padding:0;
    height: 100%;
    width: 100%;
}
table {
    border-collapse: collapse; /* make simple 1px lines borders if border defined */
}
tr {
    width: 100%;
}

.outer-container {
    background-color: #ccc;    
    top:0;
    left: 0;
    right: 300px;
    bottom:40px;
    overflow:hidden;

}
.inner-container {
    width: 100%;
    height: 100%;
    position: relative;

}
.table-header {
    float:left;
    width: 100%;
}
.table-body {
    float:left;
    height: 100%;
    width: inherit;

}
.header-cell {
    background-color: yellow;
    text-align: left;
    height: 40px;
}
.body-cell {
    background-color: blue;
    text-align: left;
}
.col1, .col3, .col4, .col5 {
    width:120px;
    min-width: 120px;
}
.col2 {
    min-width: 300px;
}

Fixed positioned div within a relative parent div

This question came first on Google although an old one so I'm posting the working answer I found, which can be of use to someone else.

This requires 3 divs including the fixed div.

HTML

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

CSS

.wrapper { position:relative; width:1280px; }
    .parent { position:absolute; }
        .child { position:fixed; width:960px; }

How to make a div have a fixed size?

Try the following css:

#innerbox
{
   width:250px; /* or whatever width you want. */
   max-width:250px; /* or whatever width you want. */
   display: inline-block;
}

This makes the div take as little space as possible, and its width is defined by the css.

// Expanded answer

To make the buttons fixed widths do the following :

#innerbox input
{
   width:150px; /* or whatever width you want. */
   max-width:150px; /* or whatever width you want. */
}

However, you should be aware that as the size of the text changes, so does the space needed to display it. As such, it's natural that the containers need to expand. You should perhaps review what you are trying to do; and maybe have some predefined classes that you alter on the fly using javascript to ensure the content placement is perfect.

Stop fixed position at footer

I ran into this same issue recently, posted the my solution also here: Preventing element from displaying on top of footer when using position:fixed

You can achieve a solution leveraging the position property of the element with jQuery, switching between the default value (static for divs), fixed and absolute. You will also need a container element for your fixed element. Finally, in order to prevent the fixed element to go over the footer, this container element can't be the parent of the footer.

The javascript part involves calculating the distance in pixels between your fixed element and the top of the document, and comparing it with the current vertical position of the scrollbar relatively to the window object (i.e. the number of pixels above that are hidden from the visible area of the page) every time the user scrolls the page. When, on scrolling down, the fixed element is about to disappear above, we change its position to fixed and stick on top of the page.

This causes the fixed element to go over the footer when we scroll to the bottom, especially if the browser window is small. Therefore, we will calculate the distance in pixels of the footer from the top of the document and compare it with the height of the fixed element plus the vertical position of the scrollbar: when the fixed element is about to go over the footer, we will change its position to absolute and stick at the bottom, just over the footer.

Here's a generic example.

The HTML structure:

<div id="content">
    <div id="leftcolumn">
        <div class="fixed-element">
            This is fixed 
        </div>
    </div>
    <div id="rightcolumn">Main content here</div>
    <div id="footer"> The footer </div>
</div>

The CSS:

#leftcolumn {
    position: relative;
}
.fixed-element {
    width: 180px;
}
.fixed-element.fixed {
    position: fixed;
    top: 20px;
}
.fixed-element.bottom {
    position: absolute;
    bottom: 356px; /* Height of the footer element, plus some extra pixels if needed */
}

The JS:

// Position of fixed element from top of the document
var fixedElementOffset = $('.fixed-element').offset().top;
// Position of footer element from top of the document.
// You can add extra distance from the bottom if needed,
// must match with the bottom property in CSS
var footerOffset = $('#footer').offset().top - 36;

var fixedElementHeight = $('.fixed-element').height(); 

// Check every time the user scrolls
$(window).scroll(function (event) {

    // Y position of the vertical scrollbar
    var y = $(this).scrollTop();

    if ( y >= fixedElementOffset && ( y + fixedElementHeight ) < footerOffset ) {
        $('.fixed-element').addClass('fixed');
        $('.fixed-element').removeClass('bottom');          
    }
    else if ( y >= fixedElementOffset && ( y + fixedElementHeight ) >= footerOffset ) {
        $('.fixed-element').removeClass('fixed');           
        $('.fixed-element').addClass('bottom');
    }
    else {
        $('.fixed-element').removeClass('fixed bottom');
    }

 });

How can I fix the form size in a C# Windows Forms application and not to let user change its size?

Try to set

this.MinimumSize = new Size(140, 480);
this.MaximumSize = new Size(140, 480);

How to fix a header on scroll

 $(document).ready(function(){

    var div=$('#header');
    var start=$(div).offset().top;

    $.event.add(window,'scroll',function(){
        var p=$(window).scrollTop();
        $(div).css('position',(p>start)?'fixed':'static');
        $(div).css('top',(p>start)?'0px':'');

    }); 
});

It works perfectly.

Passing an array as an argument to a function in C

1. Standard array usage in C with natural type decay from array to ptr

@Bo Persson correctly states in his great answer here:

When passing an array as a parameter, this
void arraytest(int a[])
means exactly the same as
void arraytest(int *a)

However, let me add also that the above two forms also:

mean exactly the same as
```
 void arraytest(int a[0])
```
which means exactly the same as
```
 void arraytest(int a[1])
```
which means exactly the same as
```
 void arraytest(int a[2])
```
which means exactly the same as
```
 void arraytest(int a[1000])
```
etc.

In every single one of the array examples above, and as shown in the example calls in the code just below, the input parameter type decays to an int *, and can be called with no warnings and no errors, even with build options -Wall -Wextra -Werror turned on (see my repo here for details on these 3 build options), like this:

int array1[2];
int * array2 = array1;

// works fine because `array1` automatically decays from an array type
// to `int *`
arraytest(array1);
// works fine because `array2` is already an `int *` 
arraytest(array2);

As a matter of fact, the "size" value ([0], [1], [2], [1000], etc.) inside the array parameter here is apparently just for aesthetic/self-documentation purposes, and can be any positive integer (size_t type I think) you want!

In practice, however, you should use it to specify the minimum size of the array you expect the function to receive, so that when writing code it's easy for you to track and verify. The MISRA-C-2012 standard (buy/download the 236-pg 2012-version PDF of the standard for £15.00 here) goes so far as to state (emphasis added):

Rule 17.5 The function argument corresponding to a parameter declared to have an array type shall have an appropriate number of elements.

...

If a parameter is declared as an array with a specified size, the corresponding argument in each function call should point into an object that has at least as many elements as the array.

...

The use of an array declarator for a function parameter specifies the function interface more clearly than using a pointer. The minimum number of elements expected by the function is explicitly stated, whereas this is not possible with a pointer.

In other words, they recommend using the explicit size format, even though the C standard technically doesn't enforce it--it at least helps clarify to you as a developer, and to others using the code, what size array the function is expecting you to pass in.

2. Forcing type safety on arrays in C

(Not recommended, but possible. See my brief argument against doing this at the end.)

As @Winger Sendon points out in a comment below my answer, we can force C to treat an array type to be different based on the array size!

First, you must recognize that in my example just above, using the int array1[2]; like this: arraytest(array1); causes array1 to automatically decay into an int *. HOWEVER, if you take the address of array1 instead and call arraytest(&array1), you get completely different behavior! Now, it does NOT decay into an int *! Instead, the type of &array1 is int (*)[2], which means "pointer to an array of size 2 of int", or "pointer to an array of size 2 of type int", or said also as "pointer to an array of 2 ints". So, you can FORCE C to check for type safety on an array, like this:

void arraytest(int (*a)[2])
{
    // my function here
}

This syntax is hard to read, but similar to that of a function pointer. The online tool, cdecl, tells us that int (*a)[2] means: "declare a as pointer to array 2 of int" (pointer to array of 2 ints). Do NOT confuse this with the version withOUT parenthesis: int * a[2], which means: "declare a as array 2 of pointer to int" (AKA: array of 2 pointers to int, AKA: array of 2 int*s).

Now, this function REQUIRES you to call it with the address operator (&) like this, using as an input parameter a POINTER TO AN ARRAY OF THE CORRECT SIZE!:

int array1[2];

// ok, since the type of `array1` is `int (*)[2]` (ptr to array of 
// 2 ints)
arraytest(&array1); // you must use the & operator here to prevent
                    // `array1` from otherwise automatically decaying
                    // into `int *`, which is the WRONG input type here!

This, however, will produce a warning:

int array1[2];

// WARNING! Wrong type since the type of `array1` decays to `int *`:
//      main.c:32:15: warning: passing argument 1 of ‘arraytest’ from 
//      incompatible pointer type [-Wincompatible-pointer-types]                                                            
//      main.c:22:6: note: expected ‘int (*)[2]’ but argument is of type ‘int *’
arraytest(array1); // (missing & operator)

You may test this code here.

To force the C compiler to turn this warning into an error, so that you MUST always call arraytest(&array1); using only an input array of the corrrect size and type (int array1[2]; in this case), add -Werror to your build options. If running the test code above on onlinegdb.com, do this by clicking the gear icon in the top-right and click on "Extra Compiler Flags" to type this option in. Now, this warning:

main.c:34:15: warning: passing argument 1 of ‘arraytest’ from incompatible pointer type [-Wincompatible-pointer-types]                                                            
main.c:24:6: note: expected ‘int (*)[2]’ but argument is of type ‘int *’

will turn into this build error:

main.c: In function ‘main’:
main.c:34:15: error: passing argument 1 of ‘arraytest’ from incompatible pointer type [-Werror=incompatible-pointer-types]
     arraytest(array1); // warning!
               ^~~~~~
main.c:24:6: note: expected ‘int (*)[2]’ but argument is of type ‘int *’
 void arraytest(int (*a)[2])
      ^~~~~~~~~
cc1: all warnings being treated as errors

Note that you can also create "type safe" pointers to arrays of a given size, like this:

int array[2];
// "type safe" ptr to array of size 2 of int:
int (*array_p)[2] = &array;

...but I do NOT necessarily recommend this (using these "type safe" arrays in C), as it reminds me a lot of the C++ antics used to force type safety everywhere, at the exceptionally high cost of language syntax complexity, verbosity, and difficulty architecting code, and which I dislike and have ranted about many times before (ex: see "My Thoughts on C++" here).

For additional tests and experimentation, see also the link just below.

References

See links above. Also:

My code experimentation online: https://onlinegdb.com/B1RsrBDFD

Shortcut for changing font size

Ctrl + MouseWheel on active editor.

Spring RestTemplate timeout

RestTemplate timeout with SimpleClientHttpRequestFactory To programmatically override the timeout properties, we can customize the SimpleClientHttpRequestFactory class as below.

Override timeout with SimpleClientHttpRequestFactory

//Create resttemplate
RestTemplate restTemplate = new RestTemplate(getClientHttpRequestFactory());

//Override timeouts in request factory
private SimpleClientHttpRequestFactory getClientHttpRequestFactory() 
{
    SimpleClientHttpRequestFactory clientHttpRequestFactory
                      = new SimpleClientHttpRequestFactory();
    //Connect timeout
    clientHttpRequestFactory.setConnectTimeout(10_000);

    //Read timeout
    clientHttpRequestFactory.setReadTimeout(10_000);
    return clientHttpRequestFactory;
}

RestTemplate timeout with HttpComponentsClientHttpRequestFactory SimpleClientHttpRequestFactory helps in setting timeout but it is very limited in functionality and may not prove sufficient in realtime applications. In production code, we may want to use HttpComponentsClientHttpRequestFactory which support HTTP Client library along with resttemplate.

HTTPClient provides other useful features such as connection pool, idle connection management etc.

Override timeout with HttpComponentsClientHttpRequestFactory

//Create resttemplate
RestTemplate restTemplate = new RestTemplate(getClientHttpRequestFactory());

//Override timeouts in request factory
private SimpleClientHttpRequestFactory getClientHttpRequestFactory() 
{
    HttpComponentsClientHttpRequestFactory clientHttpRequestFactory
                      = new HttpComponentsClientHttpRequestFactory();
    //Connect timeout
    clientHttpRequestFactory.setConnectTimeout(10_000);

    //Read timeout
    clientHttpRequestFactory.setReadTimeout(10_000);
    return clientHttpRequestFactory;
}

reference: Spring RestTemplate timeout configuration example

How to read a list of files from a folder using PHP?

If you have problems with accessing to the path, maybe you need to put this:

$root = $_SERVER['DOCUMENT_ROOT'];
$path = "/cv/"; 

// Open the folder
 $dir_handle = @opendir($root . $path) or die("Unable to open $path");

Regex to check whether a string contains only numbers

Maybe it works:

let a = "1234"
parseInt(a) == a // true
let b = "1234abc"
parseInt(b) == b // false

How to change value for innodb_buffer_pool_size in MySQL on Mac OS?

In the earlier versions of MySQL ( < 5.7.5 ) the only way to set

'innodb_buffer_pool_size'

variable was by writing it to my.cnf (for linux) and my.ini (for windows) under [mysqld] section :

[mysqld]

innodb_buffer_pool_size = 2147483648

You need to restart your mysql server to have it's effect in action.

UPDATE :

As of MySQL 5.7.5, the innodb_buffer_pool_size configuration option can be set dynamically using a SET statement, allowing you to resize the buffer pool without restarting the server. For example:
mysql> SET GLOBAL innodb_buffer_pool_size=402653184;

Reference : https://dev.mysql.com/doc/refman/5.7/en/innodb-buffer-pool-resize.html

python-dev installation error: ImportError: No module named apt_pkg

This worked for me on after updating python3.7 on ubuntu18.04

cd /usr/lib/python3/dist-packages
sudo cp apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.so

What is process.env.PORT in Node.js?

In some scenarios, port can only be designated by the environment and is saved in a user environment variable. Below is how node.js apps work with it.

The process object is a global that provides information about, and control over, the current Node.js process. As a global, it is always available to Node.js applications without using require().

The process.env property returns an object containing the user environment.

An example of this object looks like:

{
  TERM: 'xterm-256color',
  SHELL: '/usr/local/bin/bash',
  USER: 'maciej',
  PATH: '~/.bin/:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin',
  PWD: '/Users/maciej',
  EDITOR: 'vim',
  SHLVL: '1',
  HOME: '/Users/maciej',
  LOGNAME: 'maciej',
  _: '/usr/local/bin/node'
}

For example,

terminal: set a new user environment variable, not permanently

export MY_TEST_PORT=9999

app.js: read the new environment variable from node app

console.log(process.env.MY_TEST_PORT)

terminal: run the node app and get the value

$ node app.js
9999

SQL Server Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >=

The error implies that this subquery is returning more than 1 row:

(Select Supplier_Item.Price from Supplier_Item,orderdetails,Supplier where Supplier_Item.SKU=OrderDetails.Sku and Supplier_Item.SupplierId=Supplier.SupplierID )

You probably don't want to include the orderdetails and supplier tables in the subquery, because you want to reference the values selected from those tables in the outer query. So I think you want the subquery to be simply:

(Select Supplier_Item.Price from Supplier_Item where Supplier_Item.SKU=OrderDetails.Sku and Supplier_Item.SupplierId=Supplier.SupplierID )

I suggest you read up on correlated vs. non-correlated subqueries.

Find out whether radio button is checked with JQuery?

This will work in all versions of jquery.

//-- Check if there's no checked radio button
if ($('#radio_button').is(':checked') === false ) {
  //-- if none, Do something here    
}

To activate some function when a certain radio button is checked.

// get it from your form or parent id
    if ($('#your_form').find('[name="radio_name"]').is(':checked') === false ) {
      $('#your_form').find('[name="radio_name"]').filter('[value=' + checked_value + ']').prop('checked', true);
    }

your html

_x000D_

$('document').ready(function() {
var checked_value = 'checked';
  if($("#your_form").find('[name="radio_name"]').is(":checked") === false) {
      $("#your_form")
        .find('[name="radio_name"]')
        .filter("[value=" + checked_value + "]")
        .prop("checked", true);
    }
  }
)

_x000D_

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form action="" id="your_form">
  <input id="user" name="radio_name" type="radio" value="checked">
        <label for="user">user</label>
  <input id="admin" name="radio_name" type="radio" value="not_this_one">
    <label for="admin">Admin</label>
</form>

_x000D_

How to create a RelativeLayout programmatically with two buttons one on top of the other?

Found the answer in How to lay out Views in RelativeLayout programmatically?

We should explicitly set id's using setId(). Only then, RIGHT_OF rules make sense.

Another mistake I did is, reusing the layoutparams object between the controls. We should create new object for each control

Purpose of installing Twitter Bootstrap through npm?

Use npm/bower to install bootstrap if you want to recompile it/change less files/test. With grunt it would be easier to do this, as shown on http://getbootstrap.com/getting-started/#grunt. If you only want to add precompiled libraries feel free to manually include files to project.
No, you have to do this by yourself or use separate grunt tool. For example 'grunt-contrib-concat' How to concatenate and minify multiple CSS and JavaScript files with Grunt.js (0.3.x)

Can I connect to SQL Server using Windows Authentication from Java EE webapp?

Unless you have some really compelling reason not to, I suggest ditching the MS JDBC driver.

Instead, use the jtds jdbc driver. Read the README.SSO file in the jtds distribution on how to configure for single-sign-on (native authentication) and where to put the native DLL to ensure it can be loaded by the JVM.

How to get share counts using graph API

Using FQL you could do that:

http://graph.facebook.com/fql?q=SELECT url, total_count FROM link_stat WHERE url='PASTE_YOUR_URL_HERE'

How do I set combobox read-only or user cannot write in a combo box only can select the given items?

The solution is to change the DropDownStyle property to DropDownList. It will help.

PersistenceContext EntityManager injection NullPointerException

If the component is an EJB, then, there shouldn't be a problem injecting an EM.

But....In JBoss 5, the JAX-RS integration isn't great. If you have an EJB, you cannot use scanning and you must manually list in the context-param resteasy.jndi.resource. If you still have scanning on, Resteasy will scan for the resource class and register it as a vanilla JAX-RS service and handle the lifecycle.

This is probably the problem.

Android Studio: /dev/kvm device permission denied

In order to make a virtual device in Linux - I have to follow this three command and it helps me to avoid trouble for building avd devices - the process are -

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

so, now you are good to go, restart android studio and start building application with emulator.

Horizontal swipe slider with jQuery and touch devices support?

Have you seen FlexSlider from WooThemes? I've used it on several recent projects with great success. It's touch enabled too so it will work on both mouse-based browsers as well as touch-based browsers in iOS and Android.

535-5.7.8 Username and Password not accepted

Goto config/initializers/setup_mail.rb Check whether the configuration there matches the configuration written in the development.rb file.It should look like the following in both files:

config.action_mailer.smtp_settings = {
     :address =>"[email protected]",
     :port => 587,
     :domain => "gmail.com",
     :user_name => "[email protected]",
     :password => "********",
     :authentication => 'plain',
     :enable_starttls_auto => true,
     :openssl_verify_mode => 'none' 
     }

This will most certainly solve your problem.

Is there a float input type in HTML5?

Based on this answer

<input type="text" id="sno" placeholder="Only float with dot !"   
   onkeypress="return (event.charCode >= 48 && event.charCode <= 57) ||  
   event.charCode == 46 || event.charCode == 0 ">

Meaning :

Char code :

48-57 equal to 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
0 is Backspace(otherwise need refresh page on Firefox)
46 is dot

&& is AND , || is OR operator.

if you try float with comma :

<input type="text" id="sno" placeholder="Only float with comma !"   
     onkeypress="return (event.charCode >= 48 && event.charCode <= 57) ||  
     event.charCode == 44 || event.charCode == 0 ">

Supported Chromium and Firefox (Linux X64)(other browsers I does not exist.)

How to convert WebResponse.GetResponseStream return into a string?

You can use StreamReader.ReadToEnd(),

using (Stream stream = response.GetResponseStream())
{
   StreamReader reader = new StreamReader(stream, Encoding.UTF8);
   String responseString = reader.ReadToEnd();
}

When to use dynamic vs. static libraries

If the library is static, then at link time the code is linked in with your executable. This makes your executable larger (than if you went the dynamic route).

If the library is dynamic then at link time references to the required methods are built in to your executable. This means that you have to ship your executable and the dynamic library. You also ought to consider whether shared access to the code in the library is safe, preferred load address among other stuff.

If you can live with the static library, go with the static library.

"unrecognized import path" with go get

I installed Go with brew on OSX 10.11, and found I had to set GOROOT to:

/usr/local/Cellar/go/1.5.1/libexec

(Of course replace the version in this path with go version you have)

Brew uses symlinks, which were fooling the gotool. So follow the links home.

AWS S3 copy files and folders between two buckets

How to implement oauth2 server in ASP.NET MVC 5 and WEB API 2

I also struggled finding articles on how to just generate the token part. I never found one and wrote my own. So if it helps:

The things to do are:

Create a new web application
Install the following NuGet packages:
- Microsoft.Owin
- Microsoft.Owin.Host.SystemWeb
- Microsoft.Owin.Security.OAuth
- Microsoft.AspNet.Identity.Owin
Add a OWIN startup class

Then create a HTML and a JavaScript (index.js) file with these contents:

var loginData = 'grant_type=password&[email protected]&password=test123';

var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function () {
    if (xmlhttp.readyState === 4 && xmlhttp.status === 200) {
        alert(xmlhttp.responseText);
    }
}
xmlhttp.open("POST", "/token", true);
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.send(loginData);

<!DOCTYPE html>
<html>
<head>
    <title></title>
</head>
<body>
    <script type="text/javascript" src="index.js"></script>
</body>
</html>

The OWIN startup class should have this content:

using System;
using System.Security.Claims;
using Microsoft.Owin;
using Microsoft.Owin.Security.OAuth;
using OAuth20;
using Owin;

[assembly: OwinStartup(typeof(Startup))]

namespace OAuth20
{
    public class Startup
    {
        public static OAuthAuthorizationServerOptions OAuthOptions { get; private set; }

        public void Configuration(IAppBuilder app)
        {
            OAuthOptions = new OAuthAuthorizationServerOptions()
            {
                TokenEndpointPath = new PathString("/token"),
                Provider = new OAuthAuthorizationServerProvider()
                {
                    OnValidateClientAuthentication = async (context) =>
                    {
                        context.Validated();
                    },
                    OnGrantResourceOwnerCredentials = async (context) =>
                    {
                        if (context.UserName == "[email protected]" && context.Password == "test123")
                        {
                            ClaimsIdentity oAuthIdentity = new ClaimsIdentity(context.Options.AuthenticationType);
                            context.Validated(oAuthIdentity);
                        }
                    }
                },
                AllowInsecureHttp = true,
                AccessTokenExpireTimeSpan = TimeSpan.FromDays(1)
            };

            app.UseOAuthBearerTokens(OAuthOptions);
        }
    }
}

Run your project. The token should be displayed in the pop-up.

Android Material Design Button Styles

I tried a lot of answer & third party libs, but none was keeping the border and raised effect on pre-lollipop while having the ripple effect on lollipop without drawback. Here is my final solution combining several answers (border/raised are not well rendered on gifs due to grayscale color depth) :

Lollipop

Pre-lollipop

build.gradle

compile 'com.android.support:cardview-v7:23.1.1'

layout.xml

<android.support.v7.widget.CardView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:id="@+id/card"
    card_view:cardElevation="2dp"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    card_view:cardMaxElevation="8dp"
    android:layout_margin="6dp"
    >
    <Button
        android:id="@+id/button"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_margin="0dp"
        android:background="@drawable/btn_bg"
        android:text="My button"/>
</android.support.v7.widget.CardView>

drawable-v21/btn_bg.xml

<?xml version="1.0" encoding="utf-8"?>
<ripple xmlns:android="http://schemas.android.com/apk/res/android"
    android:color="?attr/colorControlHighlight">
    <item android:drawable="?attr/colorPrimary"/>
</ripple>

drawable/btn_bg.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@color/colorPrimaryDark" android:state_pressed="true"/>
    <item android:drawable="@color/colorPrimaryDark" android:state_focused="true"/>
    <item android:drawable="@color/colorPrimary"/>
</selector>

Activity's onCreate

    final CardView cardView = (CardView) findViewById(R.id.card);
    final Button button = (Button) findViewById(R.id.button);
    button.setOnTouchListener(new View.OnTouchListener() {
        ObjectAnimator o1 = ObjectAnimator.ofFloat(cardView, "cardElevation", 2, 8)
                .setDuration
                        (80);
        ObjectAnimator o2 = ObjectAnimator.ofFloat(cardView, "cardElevation", 8, 2)
                .setDuration
                        (80);

        @Override
        public boolean onTouch(View v, MotionEvent event) {

            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    o1.start();
                    break;
                case MotionEvent.ACTION_CANCEL:
                case MotionEvent.ACTION_UP:
                    o2.start();
                    break;
            }
            return false;
        }
    });

How to check queue length in Python

len(queue) should give you the result, 3 in this case.

Specifically, len(object) function will call object.__len__ method [reference link]. And the object in this case is deque, which implements __len__ method (you can see it by dir(deque)).

queue= deque([])   #is this length 0 queue?

Yes it will be 0 for empty deque.

CSS Div width percentage and padding without breaking layout

If you want the #header to be the same width as your container, with 10px of padding, you can leave out its width declaration. That will cause it to implicitly take up its entire parent's width (since a div is by default a block level element).

Then, since you haven't defined a width on it, the 10px of padding will be properly applied inside the element, rather than adding to its width:

#container {
    position: relative;
    width: 80%;
}

#header {
    position: relative;
    height: 50px;
    padding: 10px;
}

You can see it in action here.

The key when using percentage widths and pixel padding/margins is not to define them on the same element (if you want to accurately control the size). Apply the percentage width to the parent and then the pixel padding/margin to a display: block child with no width set.

Update

Another option for dealing with this is to use the box-sizing CSS rule:

#container { 
    -webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
    -moz-box-sizing: border-box;    /* Firefox, other Gecko */
    box-sizing: border-box;         /* Opera/IE 8+ */

    /* Since this element now uses border-box sizing, the 10px of horizontal
       padding will be drawn inside the 80% width */
    width: 80%;
    padding: 0 10px;
}

Here's a post talking about how box-sizing works.

jQuery get input value after keypress

I was looking for a ES6 example (so it could pass my linter) So for other people who are looking for the same:

$('#dSuggest').keyup((e) => {
    console.log(e.currentTarget.value);
});

I would also use keyup because you get the current value that is filled in.

PHP How to find the time elapsed since a date time?

Improvisation to the function "humanTiming" by arnorhs. It would calculate a "fully stretched" translation of time string to human readable text version. For example to say it like "1 week 2 days 1 hour 28 minutes 14 seconds"

function humantime ($oldtime, $newtime = null, $returnarray = false)    {
    if(!$newtime) $newtime = time();
    $time = $newtime - $oldtime; // to get the time since that moment
    $tokens = array (
            31536000 => 'year',
            2592000 => 'month',
            604800 => 'week',
            86400 => 'day',
            3600 => 'hour',
            60 => 'minute',
            1 => 'second'
    );
    $htarray = array();
    foreach ($tokens as $unit => $text) {
            if ($time < $unit) continue;
            $numberOfUnits = floor($time / $unit);
            $htarray[$text] = $numberOfUnits.' '.$text.(($numberOfUnits>1)?'s':'');
            $time = $time - ( $unit * $numberOfUnits );
    }
    if($returnarray) return $htarray;
    return implode(' ', $htarray);
}

Async always WaitingForActivation

I overcome this issue with if anybody interested. In myMain method i called my readasync method like

Dispatcher.BeginInvoke(new ThreadStart(() => ReadData()));

Everything is fine for me now.

How to test if a string is basically an integer in quotes using Ruby

Well, here's the easy way:

class String
  def is_integer?
    self.to_i.to_s == self
  end
end

>> "12".is_integer?
=> true
>> "blah".is_integer?
=> false

I don't agree with the solutions that provoke an exception to convert the string - exceptions are not control flow, and you might as well do it the right way. That said, my solution above doesn't deal with non-base-10 integers. So here's the way to do with without resorting to exceptions:

  class String
    def integer? 
      [                          # In descending order of likeliness:
        /^[-+]?[1-9]([0-9]*)?$/, # decimal
        /^0[0-7]+$/,             # octal
        /^0x[0-9A-Fa-f]+$/,      # hexadecimal
        /^0b[01]+$/              # binary
      ].each do |match_pattern|
        return true if self =~ match_pattern
      end
      return false
    end
  end

Entity Framework - Generating Classes

1) First you need to generate EDMX model using your database. To do that you should add new item to your project:

Select ADO.NET Entity Data Model from the Templates list.
On the Choose Model Contents page, select the Generate from Database option and click Next.
Choose your database.
On the Choose Your Database Objects page, check the Tables. Choose Views or Stored Procedures if you need.

So now you have Model1.edmx file in your project.

2) To generate classes using your model:

Open your EDMX model designer.
On the design surface Right Click –> Add Code Generation Item…
Select Online templates.
Select EF 4.x DbContext Generator for C#.
Click ‘Add’.

Notice that two items are added to your project:

Model1.tt (This template generates very simple POCO classes for each entity in your model)
Model1.Context.tt (This template generates a derived DbContext to use for querying and persisting data)

3) Read/Write Data example:

 var dbContext = new YourModelClass(); //class derived from DbContext
 var contacts = from c in dbContext.Contacts select c; //read data
 contacts.FirstOrDefault().FirstName = "Alex"; //edit data
 dbContext.SaveChanges(); //save data to DB

Don't forget that you need 4.x version of EntityFramework. You can download EF 4.1 here: Entity Framework 4.1.

shorthand If Statements: C#

Yes. Use the ternary operator.

condition ? true_expression : false_expression;

Capitalize only first character of string and leave others alone? (Rails)

str.sub(/./, &:capitalize)

How can I convert a file pointer ( FILE* fp ) to a file descriptor (int fd)?

The proper function is int fileno(FILE *stream). It can be found in <stdio.h>, and is a POSIX standard but not standard C.

.NET NewtonSoft JSON deserialize map to a different property name

Expanding Rentering.com's answer, in scenarios where a whole graph of many types is to be taken care of, and you're looking for a strongly typed solution, this class can help, see usage (fluent) below. It operates as either a black-list or white-list per type. A type cannot be both (Gist - also contains global ignore list).

public class PropertyFilterResolver : DefaultContractResolver
{
  const string _Err = "A type can be either in the include list or the ignore list.";
  Dictionary<Type, IEnumerable<string>> _IgnorePropertiesMap = new Dictionary<Type, IEnumerable<string>>();
  Dictionary<Type, IEnumerable<string>> _IncludePropertiesMap = new Dictionary<Type, IEnumerable<string>>();
  public PropertyFilterResolver SetIgnoredProperties<T>(params Expression<Func<T, object>>[] propertyAccessors)
  {
    if (propertyAccessors == null) return this;

    if (_IncludePropertiesMap.ContainsKey(typeof(T))) throw new ArgumentException(_Err);

    var properties = propertyAccessors.Select(GetPropertyName);
    _IgnorePropertiesMap[typeof(T)] = properties.ToArray();
    return this;
  }

  public PropertyFilterResolver SetIncludedProperties<T>(params Expression<Func<T, object>>[] propertyAccessors)
  {
    if (propertyAccessors == null)
      return this;

    if (_IgnorePropertiesMap.ContainsKey(typeof(T))) throw new ArgumentException(_Err);

    var properties = propertyAccessors.Select(GetPropertyName);
    _IncludePropertiesMap[typeof(T)] = properties.ToArray();
    return this;
  }

  protected override IList<JsonProperty> CreateProperties(Type type, MemberSerialization memberSerialization)
  {
    var properties = base.CreateProperties(type, memberSerialization);

    var isIgnoreList = _IgnorePropertiesMap.TryGetValue(type, out IEnumerable<string> map);
    if (!isIgnoreList && !_IncludePropertiesMap.TryGetValue(type, out map))
      return properties;

    Func<JsonProperty, bool> predicate = jp => map.Contains(jp.PropertyName) == !isIgnoreList;
    return properties.Where(predicate).ToArray();
  }

  string GetPropertyName<TSource, TProperty>(
  Expression<Func<TSource, TProperty>> propertyLambda)
  {
    if (!(propertyLambda.Body is MemberExpression member))
      throw new ArgumentException($"Expression '{propertyLambda}' refers to a method, not a property.");

    if (!(member.Member is PropertyInfo propInfo))
      throw new ArgumentException($"Expression '{propertyLambda}' refers to a field, not a property.");

    var type = typeof(TSource);
    if (!type.GetTypeInfo().IsAssignableFrom(propInfo.DeclaringType.GetTypeInfo()))
      throw new ArgumentException($"Expresion '{propertyLambda}' refers to a property that is not from type '{type}'.");

    return propInfo.Name;
  }
}

Usage:

var resolver = new PropertyFilterResolver()
  .SetIncludedProperties<User>(
    u => u.Id, 
    u => u.UnitId)
  .SetIgnoredProperties<Person>(
    r => r.Responders)
  .SetIncludedProperties<Blog>(
    b => b.Id)
  .Ignore(nameof(IChangeTracking.IsChanged)); //see gist

What is JSONP, and why was it created?

The great answers have already been given, I just need to give my piece in the form of code blocks in javascript (I will also include more modern and better solution for cross-origin requests: CORS with HTTP Headers):

JSONP:

1.client_jsonp.js

$.ajax({
    url: "http://api_test_server.proudlygeek.c9.io/?callback=?",
    dataType: "jsonp",
    success: function(data) {
        console.log(data);    
    }
});??????????????????

2.server_jsonp.js

var http = require("http"),
    url  = require("url");

var server = http.createServer(function(req, res) {

    var callback = url.parse(req.url, true).query.callback || "myCallback";
    console.log(url.parse(req.url, true).query.callback);

    var data = {
        'name': "Gianpiero",
        'last': "Fiorelli",
        'age': 37
    };

    data = callback + '(' + JSON.stringify(data) + ');';

    res.writeHead(200, {'Content-Type': 'application/json'});
    res.end(data);
});

server.listen(process.env.PORT, process.env.IP);

console.log('Server running at '  + process.env.PORT + ':' + process.env.IP);

CORS:

3.client_cors.js

$.ajax({
    url: "http://api_test_server.proudlygeek.c9.io/",
    success: function(data) {
        console.log(data);    
    }
});?

4.server_cors.js

var http = require("http"),
    url  = require("url");

var server = http.createServer(function(req, res) {
    console.log(req.headers);

    var data = {
        'name': "Gianpiero",
        'last': "Fiorelli",
        'age': 37
    };

    res.writeHead(200, {
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*'
    });

    res.end(JSON.stringify(data));
});

server.listen(process.env.PORT, process.env.IP);

console.log('Server running at '  + process.env.PORT + ':' + process.env.IP);

How to break long string to multiple lines

You cannot use the VB line-continuation character inside of a string.

SqlQueryString = "Insert into Employee values(" & txtEmployeeNo.Value & _
"','" & txtContractStartDate.Value &  _
"','" & txtSeatNo.Value & _
"','" & txtFloor.Value & "','" & txtLeaves.Value & "')"

What .NET collection provides the fastest search

If you don't need ordering, try HashSet<Record> (new to .Net 3.5)

If you do, use a List<Record> and call BinarySearch.

Mongoose limit/offset and count query

Instead of using 2 separate queries, you can use aggregate() in a single query:

Aggregate "$facet" can be fetch more quickly, the Total Count and the Data with skip & limit

    db.collection.aggregate([

      //{$sort: {...}}

      //{$match:{...}}

      {$facet:{

        "stage1" : [ {"$group": {_id:null, count:{$sum:1}}} ],

        "stage2" : [ { "$skip": 0}, {"$limit": 2} ]
  
      }},
     
     {$unwind: "$stage1"},
  
      //output projection
     {$project:{
        count: "$stage1.count",
        data: "$stage2"
     }}

 ]);

output as follows:-

[{
     count: 50,
     data: [
        {...},
        {...}
      ]
 }]

Also, have a look at https://docs.mongodb.com/manual/reference/operator/aggregation/facet/

Which is preferred: Nullable<T>.HasValue or Nullable<T> != null?

I did some research on this by using different methods to assign values to a nullable int. Here is what happened when I did various things. Should clarify what's going on. Keep in mind: Nullable<something> or the shorthand something? is a struct for which the compiler seems to be doing a lot of work to let us use with null as if it were a class.
As you'll see below, SomeNullable == null and SomeNullable.HasValue will always return an expected true or false. Although not demonstrated below, SomeNullable == 3 is valid too (assuming SomeNullable is an int?).
While SomeNullable.Value gets us a runtime error if we assigned null to SomeNullable. This is in fact the only case where nullables could cause us a problem, thanks to a combination of overloaded operators, overloaded object.Equals(obj) method, and compiler optimization and monkey business.

Here is a description of some code I ran, and what output it produced in labels:

int? val = null;
lbl_Val.Text = val.ToString(); //Produced an empty string.
lbl_ValVal.Text = val.Value.ToString(); //Produced a runtime error. ("Nullable object must have a value.")
lbl_ValEqNull.Text = (val == null).ToString(); //Produced "True" (without the quotes)
lbl_ValNEqNull.Text = (val != null).ToString(); //Produced "False"
lbl_ValHasVal.Text = val.HasValue.ToString(); //Produced "False"
lbl_NValHasVal.Text = (!(val.HasValue)).ToString(); //Produced "True"
lbl_ValValEqNull.Text = (val.Value == null).ToString(); //Produced a runtime error. ("Nullable object must have a value.")
lbl_ValValNEqNull.Text = (val.Value != null).ToString(); //Produced a runtime error. ("Nullable object must have a value.")

Ok, lets try the next initialization method:

int? val = new int?();
lbl_Val.Text = val.ToString(); //Produced an empty string.
lbl_ValVal.Text = val.Value.ToString(); //Produced a runtime error. ("Nullable object must have a value.")
lbl_ValEqNull.Text = (val == null).ToString(); //Produced "True" (without the quotes)
lbl_ValNEqNull.Text = (val != null).ToString(); //Produced "False"
lbl_ValHasVal.Text = val.HasValue.ToString(); //Produced "False"
lbl_NValHasVal.Text = (!(val.HasValue)).ToString(); //Produced "True"
lbl_ValValEqNull.Text = (val.Value == null).ToString(); //Produced a runtime error. ("Nullable object must have a value.")
lbl_ValValNEqNull.Text = (val.Value != null).ToString(); //Produced a runtime error. ("Nullable object must have a value.")

All the same as before. Keep in mind that initializing with int? val = new int?(null);, with null passed to the constructor, would have produced a COMPILE time error, since the nullable object's VALUE is NOT nullable. It is only the wrapper object itself that can equal null.

Likewise, we would get a compile time error from:

int? val = new int?();
val.Value = null;

not to mention that val.Value is a read-only property anyway, meaning we can't even use something like:

val.Value = 3;

but again, polymorphous overloaded implicit conversion operators let us do:

val = 3;

No need to worry about polysomthing whatchamacallits though, so long as it works right? :)

How to hide a mobile browser's address bar?

create host file = manifest.json

html tag head

<link rel="manifest" href="/manifest.json">

file

manifest.json

{
"name": "news",
"short_name": "news",
"description": "des news application day",
"categories": [
"news",
"business"
],
"theme_color": "#ffffff",
"background_color": "#ffffff",
"display": "standalone",
"orientation": "natural",
"lang": "fa",
"dir": "rtl",
"start_url": "/?application=true",
"gcm_sender_id": "482941778795",
"DO_NOT_CHANGE_GCM_SENDER_ID": "Do not change the GCM Sender ID",
"icons": [
{
"src": "https://s100.divarcdn.com/static/thewall-assets/android-chrome-192x192.png",
"sizes": "192x192",
"type": "image/png"
},
{
"src": "https://s100.divarcdn.com/static/thewall-assets/android-chrome-512x512.png",
"sizes": "512x512",
"type": "image/png"
}
],
"related_applications": [
{
"platform": "play",
"url": "https://play.google.com/store/apps/details?id=ir.divar"
}
],
"prefer_related_applications": true
}

log4j:WARN No appenders could be found for logger in web.xml

You may get this error when your log4j.properties are not present in the classpath.

This means you have to move the log4j.properties into the src folder and set the output to the bin folder so that at run time log4j.properties will read from the bin folder and your error will be resolved easily.

When should I use semicolons in SQL Server?

From a SQLServerCentral.Com article by Ken Powers:

The Semicolon

The semicolon character is a statement terminator. It is a part of the ANSI SQL-92 standard, but was never used within Transact-SQL. Indeed, it was possible to code T-SQL for years without ever encountering a semicolon.

Usage

There are two situations in which you must use the semicolon. The first situation is where you use a Common Table Expression (CTE), and the CTE is not the first statement in the batch. The second is where you issue a Service Broker statement and the Service Broker statement is not the first statement in the batch.

Wget output document and headers to STDOUT

This will not work:

wget -q -S -O - google.com 1>wget.txt 2>&1

since redirects are evaluated right to left, this sends html to wget.txt and the header to STDOUT:

wget -q -S -O - google.com 2>&1 1>wget.txt

Send string to stdin

You can use one-line heredoc

cat <<< "This is coming from the stdin"

the above is the same as

cat <<EOF
This is coming from the stdin
EOF

or you can redirect output from a command, like

diff <(ls /bin) <(ls /usr/bin)

or you can read as

while read line
do
   echo =$line=
done < some_file

or simply

echo something | read param

Display last git commit comment

If you want to see just the subject (first line) of the commit message:

git log -1 --format=%s

This was not previously documented in any answer. Alternatively, the approach by nos also shows it.

Reference:

git log - emsem

How can I find out which server hosts LDAP on my windows domain?

If you're using AD you can use serverless binding to locate a domain controller for the default domain, then use LDAP://rootDSE to get information about the directory server, as described in the linked article.

Gradle - Error Could not find method implementation() for arguments [com.android.support:appcompat-v7:26.0.0]

Make sure you're adding these dependencies in android/app/build.gradle, not android/build.gradle

Error: Java: invalid target release: 11 - IntelliJ IDEA

I've got the same info messages and error message today, but I have recently updated Idea -> 2018.3.3, built on January 9, 2019.
To resolve this issue I've changed File->Project Structure->Modules ->> Language level to 10.
And check File -> Settings -> Build, Execution, Deployment -> Compiler -> Java Compiler ->> Project bytecode and Per-module bytecode versions. I have 11 there.
Now I don't get these notifications and the error.

It could be useful for someone like me, having the most recent Idea and getting the same error.

git cherry-pick says "...38c74d is a merge but no -m option was given"

-m means the parent number.

From the git doc:

Usually you cannot cherry-pick a merge because you do not know which side of the merge should be considered the mainline. This option specifies the parent number (starting from 1) of the mainline and allows cherry-pick to replay the change relative to the specified parent.

For example, if your commit tree is like below:

- A - D - E - F -   master
   \     /
    B - C           branch one

then git cherry-pick E will produce the issue you faced.

git cherry-pick E -m 1 means using D-E, while git cherry-pick E -m 2 means using B-C-E.

How to get just the date part of getdate()?

try this:

select convert (date ,getdate())

select CAST (getdate() as DATE)

select convert(varchar(10), getdate(),121)

Composer update memory limit

This error can occur especially when you are updating large libraries or libraries with a lot of dependencies. Composer can be quite memory hungry.

Be sure that your composer itself is updated to the latest version:

php composer.phar --self-update

You can increase the memory limit for composer temporarily by adding the composer memory limit environment variable:

COMPOSER_MEMORY_LIMIT=128MB php composer.phar update

Use the format “128M” for megabyte or “2G” for gigabyte. You can use the value “-1” to ignore the memory limit completely.

Another way would be to increase the PHP memory limit:

php -d memory_limit=512M composer.phar update ...

Why does this CSS margin-top style not work?

What @BoltClock mentioned are pretty solid. And Here I just want to add several more solutions for this problem. check this w3c_collapsing margin. The green parts are the potential thought how this problem can be solved.

Solution 1

Margins between a floated box and any other box do not collapse (not even between a float and its in-flow children).

that means I can add float:left to either #outer or #inner demo1.

also notice that float would invalidate the auto in margin.

Solution 2

Margins of elements that establish new block formatting contexts (such as floats and elements with 'overflow' other than 'visible') do not collapse with their in-flow children.

other than visible, let's put overflow: hidden into #outer. And this way seems pretty simple and decent. I like it.

#outer{
    width: 500px;
    height: 200px;
    background: #FFCCCC;
    margin: 50px auto;
    overflow: hidden;
}
#inner {
    background: #FFCC33;
    height: 50px;
    margin: 50px;
}

Solution 3

Margins of absolutely positioned boxes do not collapse (not even with their in-flow children).

#outer{
    width: 500px;
    height: 200px;
    background: #FFCCCC;
    margin: 50px auto;
    position: absolute; 
}
#inner{
    background: #FFCC33;
    height: 50px;
    margin: 50px;
}

#outer{
    width: 500px;
    height: 200px;
    background: #FFCCCC;
    margin: 50px auto;
    position: relative; 
}
#inner {
    background: #FFCC33;
    height: 50px;
    margin: 50px;
    position: absolute;
}

these two methods will break the normal flow of div

Solution 4

Margins of inline-block boxes do not collapse (not even with their in-flow children).

is the same as @enderskill

Solution 5

The bottom margin of an in-flow block-level element always collapses with the top margin of its next in-flow block-level sibling, unless that sibling has clearance.

This has not much work to do with the question since it is the collapsing margin between siblings. it generally means if a top-box has margin-bottom: 30px and a sibling-box has margin-top: 10px. The total margin between them is 30px instead of 40px.

Solution 6

The top margin of an in-flow block element collapses with its first in-flow block-level child's top margin if the element has no top border, no top padding, and the child has no clearance.

This is very interesting and I can just add one top border line

#outer{
    width: 500px;
    height: 200px;
    background: #FFCCCC;
    margin: 50px auto;
    border-top: 1px solid red;

}
#inner {
    background: #FFCC33;
    height: 50px;
    margin: 50px;

}

And Also <div> is block-level in default, so you don't have to declare it on purpose. Sorry for not being able to post more than 2 links and images due to my novice reputation. At least you know where the problem comes from next time you see something similar.

Sum all the elements java arraylist

Not very hard, just use m.get(i) to get the value from the list.

public double incassoMargherita()
{
    double sum = 0;
    for(int i = 0; i < m.size(); i++)
    {
        sum += m.get(i);
    }
    return sum;
}

'nuget' is not recognized but other nuget commands working

In Visual Studio:

Tools -> Nuget Package Manager -> Package Manager Console.

In PM:

Install-Package NuGet.CommandLine

Close Visual Studio and open it again.

System.currentTimeMillis() vs. new Date() vs. Calendar.getInstance().getTime()

If you're USING a date then I strongly advise that you use jodatime, http://joda-time.sourceforge.net/. Using System.currentTimeMillis() for fields that are dates sounds like a very bad idea because you'll end up with a lot of useless code.

Both date and calendar are seriously borked, and Calendar is definitely the worst performer of them all.

I'd advise you to use System.currentTimeMillis() when you are actually operating with milliseconds, for instance like this

 long start = System.currentTimeMillis();
    .... do something ...
 long elapsed = System.currentTimeMillis() -start;

How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?

One command to convert date time to Unix format and then to string

    DateTime.strptime(Time.now.utc.to_i.to_s,'%s').strftime("%d %m %y")

    Time.now.utc.to_i #Converts time from Unix format
    DateTime.strptime(Time.now.utc.to_i.to_s,'%s') #Converts date and time from unix format to DateTime

finally strftime is used to format date

Example:

    irb(main):034:0> DateTime.strptime("1410321600",'%s').strftime("%d %m %y")
    "10 09 14"

drop down list value in asp.net

In simple way, Its not possible. Because DropdownList contain ListItem and it will be selected by default

But, you can use ValidationControl for that:

<asp:RequiredFieldValidator InitialValue="-1" ID="Req_ID" Display="Dynamic" 
ValidationGroup="g1" runat="server" ControlToValidate="ControlID"
Text="*" ErrorMessage="ErrorMessage"></asp:RequiredFieldValidator>

Chrome desktop notification example

Notify.js is a wrapper around the new webkit notifications. It works pretty well.

http://alxgbsn.co.uk/2013/02/20/notify-js-a-handy-wrapper-for-the-web-notifications-api/

How to compare datetime with only date in SQL Server

Of-course this is an old thread but to make it complete.

From SQL 2008 you can use DATE datatype so you can simply do:

SELECT CONVERT(DATE,GETDATE())

OR

Select * from [User] U
where  CONVERT(DATE,U.DateCreated) = '2014-02-07'

How to copy java.util.list Collection

You may create a new list with an input of a previous list like so:

List one = new ArrayList()
//... add data, sort, etc
List two = new ArrayList(one);

This will allow you to modify the order or what elemtents are contained independent of the first list.

Keep in mind that the two lists will contain the same objects though, so if you modify an object in List two, the same object will be modified in list one.

example:

MyObject value1 = one.get(0);
MyObject value2 = two.get(0);
value1 == value2 //true
value1.setName("hello");
value2.getName(); //returns "hello"

Edit

To avoid this you need a deep copy of each element in the list like so:

List<Torero> one = new ArrayList<Torero>();
//add elements

List<Torero> two = new Arraylist<Torero>();
for(Torero t : one){
    Torero copy = deepCopy(t);
    two.add(copy);
}

with copy like the following:

public Torero deepCopy(Torero input){
    Torero copy = new Torero();
    copy.setValue(input.getValue());//.. copy primitives, deep copy objects again

    return copy;
}

How to get a view table query (code) in SQL Server 2008 Management Studio

Use sp_helptext before the view_name. Example:

sp_helptext Example_1

Hence you will get the query:

CREATE VIEW dbo.Example_1
AS
SELECT       a, b, c
FROM         dbo.table_name JOIN blah blah blah
WHERE        blah blah blah

sp_helptext will give stored procedures.

Get current folder path

You should not use Directory.GetCurrentDirectory() in your case, as the current directory may differ from the execution folder, especially when you execute the program through a shortcut.

It's better to use Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location); for your purpose. This returns the pathname where the currently executing assembly resides.

While my suggested approach allows you to differentiate between the executing assembly, the entry assembly or any other loaded assembly, as Soner Gönül said in his answer,

System.IO.Path.GetDirectoryName(Application.ExecutablePath);

may also be sufficient. This would be equal to

System.IO.Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);

How do I create a singleton service in Angular 2?

A singleton service is a service for which only one instance exists in an app.

There are (2) ways to provide a singleton service for your application.

use the providedIn property, or
provide the module directly in the AppModule of the application

Using providedIn

Beginning with Angular 6.0, the preferred way to create a singleton service is to set providedIn to root on the service's @Injectable() decorator. This tells Angular to provide the service in the application root.

import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root',
})
export class UserService {
}

NgModule providers array

In apps built with Angular versions prior to 6.0, services are registered NgModule providers arrays as follows:

@NgModule({
  ...
  providers: [UserService],
  ...
})

If this NgModule were the root AppModule, the UserService would be a singleton and available throughout the app. Though you may see it coded this way, using the providedIn property of the @Injectable() decorator on the service itself is preferable as of Angular 6.0 as it makes your services tree-shakable.

Windows.history.back() + location.reload() jquery

You can't do window.history.back(); and location.reload(); in the same function.

window.history.back() breaks the javascript flow and redirects to previous page, location.reload() is never processed.

location.reload() has to be called on the page you redirect to when using window.history.back().

I would used an url to redirect instead of history.back, that gives you both a redirect and refresh.

TypeError: You provided an invalid object where a stream was expected. You can provide an Observable, Promise, Array, or Iterable

In your example code, you have your map operator receiving two callbacks, when it should only be receiving one. You can move your error handling code to your catch callback.

checkLogin():Observable<boolean>{
    return this.service.getData()
                       .map(response => {  
                          this.data = response;                            
                          this.checkservice=true;
                          return true;
                       })
                       .catch(error => {
                          this.router.navigate(['newpage']);
                          console.log(error);
                          return Observable.throw(error);
                       })
   }

You'll need to also import the catch and throw operators.

import 'rxjs/add/operator/catch';
import 'rxjs/add/observable/throw';

EDIT: Note that by returning Observable.throwin your catch handler, you won't actually capture the error - it will still surface to the console.

TypeScript add Object to array with push

If your example represents your real code, the problem is not in the push, it's that your constructor doesn't do anything.

You need to declare and initialize the x and y members.

Explicitly:

export class Pixel {
    public x: number;
    public y: number;   
    constructor(x: number, y: number) {
        this.x = x;
        this.y = y;
    }
}

Or implicitly:

export class Pixel {
    constructor(public x: number, public y: number) {}
}

How do I display image in Alert/confirm box in Javascript?

You can emojis!

$('#test').on('click', () => {
    alert(' Build is too fast');
})

ModuleNotFoundError: What does it mean main is not a package?

Try to run it as:

python3 -m p_03_using_bisection_search

Laravel 5 call a model function in a blade view

want to use model in view as:

{{ Product::find($id) }}

you can use in view:

<?php
$tmp = \App\Product::find($id);
?>
{{ $tmp->name }}

Hope this will help you

What is a practical use for a closure in JavaScript?

Explaining the practical use for a closure in JavaScript

When we create a function inside another function, we are creating a closure. Closures are powerful because they are capable of reading and manipulating the data of its outer functions. Whenever a function is invoked, a new scope is created for that call. The local variable declared inside the function belong to that scope and they can only be accessed from that function. When the function has finished the execution, the scope is usually destroyed.

A simple example of such function is this:

function buildName(name) {
    const greeting = "Hello, " + name;
    return greeting;
}

In above example, the function buildName() declares a local variable greeting and returns it. Every function call creates a new scope with a new local variable. After the function is done executing, we have no way to refer to that scope again, so it’s garbage collected.

But how about when we have a link to that scope?

Let’s look at the next function:

_x000D_

function buildName(name) {
    const greeting = "Hello, " + name + " Welcome ";
    const sayName = function() {
        console.log(greeting);
    };
    return sayName;
}

const sayMyName = buildName("Mandeep");
sayMyName();  // Hello, Mandeep Welcome

_x000D_

The function sayName() from this example is a closure. The sayName() function has its own local scope (with variable welcome) and has also access to the outer (enclosing) function’s scope. In this case, the variable greeting from buildName().

After the execution of buildName is done, the scope is not destroyed in this case. The sayMyName() function still has access to it, so it won’t be garbage collected. However, there is no other way of accessing data from the outer scope except the closure. The closure serves as the gateway between the global context and the outer scope.

Split string with delimiters in C

I think strsep is still the best tool for this:

while ((token = strsep(&str, ","))) my_fn(token);

That is literally one line that splits a string.

The extra parentheses are a stylistic element to indicate that we're intentionally testing the result of an assignment, not an equality operator ==.

For that pattern to work, token and str both have type char *. If you started with a string literal, then you'd want to make a copy of it first:

// More general pattern:
const char *my_str_literal = "JAN,FEB,MAR";
char *token, *str, *tofree;

tofree = str = strdup(my_str_literal);  // We own str's memory now.
while ((token = strsep(&str, ","))) my_fn(token);
free(tofree);

If two delimiters appear together in str, you'll get a token value that's the empty string. The value of str is modified in that each delimiter encountered is overwritten with a zero byte - another good reason to copy the string being parsed first.

In a comment, someone suggested that strtok is better than strsep because strtok is more portable. Ubuntu and Mac OS X have strsep; it's safe to guess that other unixy systems do as well. Windows lacks strsep, but it has strbrk which enables this short and sweet strsep replacement:

char *strsep(char **stringp, const char *delim) {
  if (*stringp == NULL) { return NULL; }
  char *token_start = *stringp;
  *stringp = strpbrk(token_start, delim);
  if (*stringp) {
    **stringp = '\0';
    (*stringp)++;
  }
  return token_start;
}

Here is a good explanation of strsep vs strtok. The pros and cons may be judged subjectively; however, I think it's a telling sign that strsep was designed as a replacement for strtok.

How do I execute code AFTER a form has loaded?

I know this is an old post. But here is how I have done it:

    public Form1(string myFile)
    {
        InitializeComponent();
        this.Show();
        if (myFile != null)
        {
            OpenFile(myFile);
        }
    }

    private void OpenFile(string myFile = null)
    {
            MessageBox.Show(myFile);
    }

How do I install a NuGet package .nupkg file locally?

Recently I want to install squirrel.windows, I tried Install-Package squirrel.windows -Version 2.0.1 from https://www.nuget.org/packages/squirrel.windows/, but it failed with some errors. So I downloaded squirrel.windows.2.0.1.nupkg and save it in D:\Downloads\, then I can install it success via Install-Package squirrel.windows -verbose -Source D:\Downloads\ -Scope CurrentUser -SkipDependencies in powershell.

How to implement the factory method pattern in C++ correctly

Factory Pattern

class Point
{
public:
  static Point Cartesian(double x, double y);
private:
};

And if you compiler does not support Return Value Optimization, ditch it, it probably does not contain much optimization at all...

How can I remove a pytz timezone from a datetime object?

To remove a timezone (tzinfo) from a datetime object:

# dt_tz is a datetime.datetime object
dt = dt_tz.replace(tzinfo=None)

If you are using a library like arrow, then you can remove timezone by simply converting an arrow object to to a datetime object, then doing the same thing as the example above.

# <Arrow [2014-10-09T10:56:09.347444-07:00]>
arrowObj = arrow.get('2014-10-09T10:56:09.347444-07:00')

# datetime.datetime(2014, 10, 9, 10, 56, 9, 347444, tzinfo=tzoffset(None, -25200))
tmpDatetime = arrowObj.datetime

# datetime.datetime(2014, 10, 9, 10, 56, 9, 347444)
tmpDatetime = tmpDatetime.replace(tzinfo=None)

Why would you do this? One example is that mysql does not support timezones with its DATETIME type. So using ORM's like sqlalchemy will simply remove the timezone when you give it a datetime.datetime object to insert into the database. The solution is to convert your datetime.datetime object to UTC (so everything in your database is UTC since it can't specify timezone) then either insert it into the database (where the timezone is removed anyway) or remove it yourself. Also note that you cannot compare datetime.datetime objects where one is timezone aware and another is timezone naive.

##############################################################################
# MySQL example! where MySQL doesn't support timezones with its DATETIME type!
##############################################################################

arrowObj = arrow.get('2014-10-09T10:56:09.347444-07:00')

arrowDt = arrowObj.to("utc").datetime

# inserts datetime.datetime(2014, 10, 9, 17, 56, 9, 347444, tzinfo=tzutc())
insertIntoMysqlDatabase(arrowDt)

# returns datetime.datetime(2014, 10, 9, 17, 56, 9, 347444)
dbDatetimeNoTz = getFromMysqlDatabase()

# cannot compare timzeone aware and timezone naive
dbDatetimeNoTz == arrowDt # False, or TypeError on python versions before 3.3

# compare datetimes that are both aware or both naive work however
dbDatetimeNoTz == arrowDt.replace(tzinfo=None) # True

How to add custom html attributes in JSX

For any custom attributes I use react-any-attr package https://www.npmjs.com/package/react-any-attr

How to generate .NET 4.0 classes from xsd?

I use XSD in a batch script to generate .xsd file and classes from XML directly :

set XmlFilename=Your__Xml__Here
set WorkingFolder=Your__Xml__Path_Here

set XmlExtension=.xml
set XsdExtension=.xsd

set XSD="C:\Program Files (x86)\Microsoft SDKs\Windows\v8.1A\bin\NETFX 4.5.1\Tools\xsd.exe"

set XmlFilePath=%WorkingFolder%%XmlFilename%%XmlExtension%
set XsdFilePath=%WorkingFolder%%XmlFilename%%XsdExtension%

%XSD% %XmlFilePath% /out:%WorkingFolder%
%XSD% %XsdFilePath% /c /out:%WorkingFolder%

Can you target <br /> with css?

This will work, but only in IE. I tested it in IE8.

br {

  border-bottom: 1px dashed #000000;
  background-color: #ffffff;
  display: block;
  }

How do I free memory in C?

You actually can't manually "free" memory in C, in the sense that the memory is released from the process back to the OS ... when you call malloc(), the underlying libc-runtime will request from the OS a memory region. On Linux, this may be done though a relatively "heavy" call like mmap(). Once this memory region is mapped to your program, there is a linked-list setup called the "free store" that manages this allocated memory region. When you call malloc(), it quickly looks though the free-store for a free block of memory at the size requested. It then adjusts the linked list to reflect that there has been a chunk of memory taken out of the originally allocated memory pool. When you call free() the memory block is placed back in the free-store as a linked-list node that indicates its an available chunk of memory.

If you request more memory than what is located in the free-store, the libc-runtime will again request more memory from the OS up to the limit of the OS's ability to allocate memory for running processes. When you free memory though, it's not returned back to the OS ... it's typically recycled back into the free-store where it can be used again by another call to malloc(). Thus, if you make a lot of calls to malloc() and free() with varying memory size requests, it could, in theory, cause a condition called "memory fragmentation", where there is enough space in the free-store to allocate your requested memory block, but not enough contiguous space for the size of the block you've requested. Thus the call to malloc() fails, and you're effectively "out-of-memory" even though there may be plenty of memory available as a total amount of bytes in the free-store.

Spring profiles and testing

Looking at Biju's answer I found a working solution.

I created an extra context-file test-context.xml:

<context:property-placeholder location="classpath:config/spring-test.properties"/>

Containing the profile:

spring.profiles.active=localtest

And loading the test with:

@RunWith(SpringJUnit4ClassRunner.class)
@TestExecutionListeners({
    TestPreperationExecutionListener.class
    })
@Transactional
@ActiveProfiles(profiles = "localtest")
@ContextConfiguration(locations = {
    "classpath:config/test-context.xml" })
public class TestContext {

  @Test
  public void testContext(){

  }
}

This saves some work when creating multiple test-cases.

cast_sender.js error: Failed to load resource: net::ERR_FAILED in Chrome

The error is try to fix a Youtube error.

The solution to avoid your Javascript-Console-Error complex is to accept that Youtube (and also other webpages) can have Javascript errors that you can't fix.

That is all.

Regexp Java for password validation

Password Requirement :

Password should be at least eight (8) characters in length where the system can support it.
Passwords must include characters from at least two (2) of these groupings: alpha, numeric, and special characters.
```
^.*(?=.{8,})(?=.*\d)(?=.*[a-zA-Z])|(?=.{8,})(?=.*\d)(?=.*[!@#$%^&])|(?=.{8,})(?=.*[a-zA-Z])(?=.*[!@#$%^&]).*$
```

I tested it and it works

How to set up datasource with Spring for HikariCP?

I have recently migrated from C3P0 to HikariCP in a Spring and Hibernate based project and it was not as easy as I had imagined and here I am sharing my findings.

For Spring Boot see my answer here

I have the following setup

Spring 4.3.8+
Hiberante 4.3.8+
Gradle 2.x
PostgreSQL 9.5

Some of the below configs are similar to some of the answers above but, there are differences.

Gradle stuff

In order to pull in the right jars, I needed to pull in the following jars

//latest driver because *brettw* see https://github.com/pgjdbc/pgjdbc/pull/849
compile 'org.postgresql:postgresql:42.2.0'
compile('com.zaxxer:HikariCP:2.7.6') {
    //they are pulled in separately elsewhere
    exclude group: 'org.hibernate', module: 'hibernate-core'
}

// Recommended to use HikariCPConnectionProvider by Hibernate in 4.3.6+    
compile('org.hibernate:hibernate-hikaricp:4.3.8.Final') {
        //they are pulled in separately elsewhere, to avoid version conflicts
        exclude group: 'org.hibernate', module: 'hibernate-core'
        exclude group: 'com.zaxxer', module: 'HikariCP'
}

// Needed for HikariCP logging if you use log4j
compile('org.slf4j:slf4j-simple:1.7.25')  
compile('org.slf4j:slf4j-log4j12:1.7.25') {
    //log4j pulled in separately, exclude to avoid version conflict
    exclude group: 'log4j', module: 'log4j'
}

Spring/Hibernate based configs

In order to get Spring & Hibernate to make use of Hikari Connection pool, you need to define the HikariDataSource and feed it into sessionFactory bean as shown below.

<!-- HikariCP Database bean -->
<bean id="dataSource" class="com.zaxxer.hikari.HikariDataSource" destroy-method="close">
    <constructor-arg ref="hikariConfig" />
</bean>

<!-- HikariConfig config that is fed to above dataSource -->
<bean id="hikariConfig" class="com.zaxxer.hikari.HikariConfig">
        <property name="poolName" value="SpringHikariPool" />
        <property name="dataSourceClassName" value="org.postgresql.ds.PGSimpleDataSource" />
        <property name="maximumPoolSize" value="20" />
        <property name="idleTimeout" value="30000" />

        <property name="dataSourceProperties">
            <props>
                <prop key="serverName">localhost</prop>
                <prop key="portNumber">5432</prop>
                <prop key="databaseName">dbname</prop>
                <prop key="user">dbuser</prop>
                <prop key="password">dbpassword</prop>
            </props>
        </property>
</bean>

<bean class="org.springframework.orm.hibernate4.LocalSessionFactoryBean" id="sessionFactory">
        <!-- Your Hikari dataSource below -->
        <property name="dataSource" ref="dataSource"/>
        <!-- your other configs go here -->
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.connection.provider_class">org.hibernate.hikaricp.internal.HikariCPConnectionProvider</prop>
                <!-- Remaining props goes here -->
            </props>
        </property>
 </bean>

Once the above are setup then, you need to add an entry to your log4j or logback and set the level to DEBUG to see Hikari Connection Pool start up.

Log4j1.2

<!-- Keep additivity=false to avoid duplicate lines -->
<logger additivity="false" name="com.zaxxer.hikari">
    <level value="debug"/>
    <!-- Your appenders goes here -->
</logger>

Logback

Via application.properties in Spring Boot

debug=true
logging.level.com.zaxxer.hikari.HikariConfig=DEBUG

Using logback.xml

<logger name="com.zaxxer.hikari" level="DEBUG" additivity="false">
    <appender-ref ref="STDOUT" />
</logger>

With the above you should be all good to go! Obviously you need to customize the HikariCP pool configs in order to get the performance that it promises.

How to write a JSON file in C#?

The example in Liam's answer saves the file as string in a single line. I prefer to add formatting. Someone in the future may want to change some value manually in the file. If you add formatting it's easier to do so.

The following adds basic JSON indentation:

 string json = JsonConvert.SerializeObject(_data.ToArray(), Formatting.Indented);

How to write oracle insert script with one field as CLOB?

Keep in mind that SQL strings can not be larger than 4000 bytes, while Pl/SQL can have strings as large as 32767 bytes. see below for an example of inserting a large string via an anonymous block which I believe will do everything you need it to do.

note I changed the varchar2(32000) to CLOB

set serveroutput ON 
CREATE TABLE testclob 
  ( 
     id NUMBER, 
     c  CLOB, 
     d  VARCHAR2(4000) 
  ); 

DECLARE 
    reallybigtextstring CLOB := '123'; 
    i                   INT; 
BEGIN 
    WHILE Length(reallybigtextstring) <= 60000 LOOP 
        reallybigtextstring := reallybigtextstring 
                               || '000000000000000000000000000000000'; 
    END LOOP; 

    INSERT INTO testclob 
                (id, 
                 c, 
                 d) 
    VALUES     (0, 
                reallybigtextstring, 
                'done'); 

    dbms_output.Put_line('I have finished inputting your clob: ' 
                         || Length(reallybigtextstring)); 
END; 

/ 
SELECT * 
FROM   testclob; 


 "I have finished inputting your clob: 60030"

Decimal to Hexadecimal Converter in Java

The easiest way to do this is:

String hexadecimalString = String.format("%x", integerValue);

Restore the mysql database from .frm files

I just copy pasted the database folders to data folder in MySQL, i.e. If you have a database called alto then find the folder alto in your MySQL -> Data folder in your backup and copy the entire alto folder and past it to newly installed MySQL -> data folder, restart the MySQL and this works perfect.

Determine path of the executing script

The answer of rakensi from Getting path of an R script is the most correct and really brilliant IMHO. Yet, it's still a hack incorporating a dummy function. I'm quoting it here, in order to have it easier found by others.

sourceDir <- getSrcDirectory(function(dummy) {dummy})

This gives the directory of the file where the statement was placed (where the dummy function is defined). It can then be used to set the working direcory and use relative paths e.g.

setwd(sourceDir)
source("other.R")

or to create absolute paths

 source(paste(sourceDir, "/other.R", sep=""))

How can I create a two dimensional array in JavaScript?

One liner to create a m*n 2 dimensional array filled with 0.

new Array(m).fill(new Array(n).fill(0));

Error "There is already an open DataReader associated with this Command which must be closed first" when using 2 distinct commands

Just add the following in your connection string:

MultipleActiveResultSets=True;

Why does my sorting loop seem to append an element where it shouldn't?

Instead of this line

if(Array[i].compareTo(Array[j])<0)

use this line

if(Array[i].trim().compareTo(Array[j].trim())<0)

and you are good to go. The reason your current code is not working is explained by other users already. This above replacement is one workaround amongst several that you could apply.

How to disable sort in DataGridView?

For extending control functionality like this, I like to use extension methods so that it can be reused easily. Here is a starter extensions file that contains an extension to disable sorting on a datagridview.

To use it, just include it in your project and call like this

myDatagridView.DisableSorting()

In my case, I added this line of code in the DataBindingComplete eventhandler of the DataGridView where I wanted sorting disabled

Imports System.ComponentModel
Imports System.Reflection
Imports System.Runtime.CompilerServices
Imports System.Windows.Forms

Public Module Extensions

<Extension()>
Public Sub DisableSorting(datagrid As DataGridView)
    For index = 0 To datagrid.Columns.Count - 1
        datagrid.Columns(index).SortMode = DataGridViewColumnSortMode.NotSortable
    Next
End Sub


End Module

How do I upgrade the Python installation in Windows 10?

Every minor version of Python, that is any 3.x and 2.x version, will install side-by-side with other versions on your computer. Only patch versions will upgrade existing installations.

So if you want to keep your installed Python 2.7 around, then just let it and install a new version using the installer. If you want to get rid of Python 2.7, you can uninstall it before or after installing a newer version—there is no difference to this.

Current Python 3 installations come with the py.exe launcher, which by default is installed into the system directory. This makes it available from the PATH, so you can automatically run it from any shell just by using py instead of python as the command. This avoids you having to put the current Python installation into PATH yourself. That way, you can easily have multiple Python installations side-by-side without them interfering with each other. When running, just use py script.py instead of python script.py to use the launcher. You can also specify a version using for example py -3 or py -3.6 to launch a specific version, otherwise the launcher will use the current default (which will usually be the latest 3.x).

Using the launcher, you can also run Python 2 scripts (which are often syntax incompatible to Python 3), if you decide to keep your Python 2.7 installation. Just use py -2 script.py to launch a script.

As for PyPI packages, every Python installation comes with its own folder where modules are installed into. So if you install a new version and you want to use modules you installed for a previous version, you will have to install them first for the new version. Current versions of the installer also offer you to install pip; it’s enabled by default, so you already have pip for every installation. Unless you explicitly add a Python installation to the PATH, you cannot just use pip though. Luckily, you can also simply use the py.exe launcher for this: py -m pip runs pip. So for example to install Beautiful Soup for Python 3.6, you could run py -3.6 -m pip install beautifulsoup4.

How to calculate the IP range when the IP address and the netmask is given?

Invert mask (XOR with ones), AND it with IP. Add 1. This will be the starting range. OR IP with mask. This will be the ending range.

How to resolve "Waiting for Debugger" message?

Not sure if this is what you are looking for, but try putting:

android:debuggable="true"

in the application tag in the AndroidManifest.xml

Counting Chars in EditText Changed Listener

This is a slightly more general answer with more explanation for future viewers.

Add a text changed listener

If you want to find the text length or do something else after the text has been changed, you can add a text changed listener to your edit text.

EditText editText = (EditText) findViewById(R.id.testEditText);
editText.addTextChangedListener(new TextWatcher() {

    @Override
    public void beforeTextChanged(CharSequence charSequence, int start, int count, int after) {

    }

    @Override
    public void onTextChanged(CharSequence charSequence, int start, int before, int count)  {

    }

    @Override
    public void afterTextChanged(Editable editable) {

    }
});

The listener needs a TextWatcher, which requires three methods to be overridden: beforeTextChanged, onTextChanged, and afterTextChanged.

Counting the characters

You can get the character count in onTextChanged or beforeTextChanged with

charSequence.length()

or in afterTextChanged with

editable.length()

Meaning of the methods

The parameters are a little confusing so here is a little extra explanation.

beforeTextChanged

beforeTextChanged(CharSequence charSequence, int start, int count, int after)

charSequence: This is the text content before the pending change is made. You should not try to change it.
start: This is the index of where the new text will be inserted. If a range is selected, then it is the beginning index of the range.
count: This is the length of selected text that is going to be replaced. If nothing is selected then count will be 0.
after: this is the length of the text to be inserted.

onTextChanged

onTextChanged(CharSequence charSequence, int start, int before, int count)

charSequence: This is the text content after the change was made. You should not try to modify this value here. Modify the editable in afterTextChanged if you need to.
start: This is the index of the start of where the new text was inserted.
before: This is the old value. It is the length of previously selected text that was replaced. This is the same value as count in beforeTextChanged.
count: This is the length of text that was inserted. This is the same value as after in beforeTextChanged.

afterTextChanged

afterTextChanged(Editable editable)

Like onTextChanged, this is called after the change has already been made. However, now the text may be modified.

editable: This is the editable text of the EditText. If you change it, though, you have to be careful not to get into an infinite loop. See the documentation for more details.

Supplemental image from this answer

HttpWebRequest using Basic authentication

Following code will solve json response if there Basic Authentication and Proxy implemented.Also IIS 7.5 Hosting Problm will resolve.

public string HttpGetByWebRequ(string uri, string username, string password)
{
//For Basic Authentication
    string authInfo = username + ":" + password;
    authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));

//For Proxy
    WebProxy proxy = new WebProxy("http://10.127.0.1:8080", true);

    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
    request.Method = "GET";
    request.Accept = "application/json; charset=utf-8";
    request.Proxy = proxy;

    request.Headers["Authorization"] = "Basic " + authInfo;

    var response = (HttpWebResponse)request.GetResponse();

    string strResponse = "";
    using (var sr = new StreamReader(response.GetResponseStream()))
    {
        strResponse= sr.ReadToEnd();

    }

    return strResponse;
}

Mercurial: how to amend the last commit?

GUI equivalent for `hg commit --amend`:

This also works from TortoiseHG's GUI (I'm using v2.5):

Swich to the 'Commit' view or, in the workbench view, select the 'working directory' entry. The 'Commit' button has an option named 'Amend current revision' (click the button's drop-down arrow to find it).

enter image description here

          ||
          ||
          \/

enter image description here

Caveat emptor:

This extra option will only be enabled if the mercurial version is at least 2.2.0, and if the current revision is not public, is not a patch and has no children. [...]

Clicking the button will call 'commit --amend' to 'amend' the revision.

More info about this on the THG dev channel

Why would an Enum implement an Interface?

Here's my reason why ...

I have populated a JavaFX ComboBox with the values of an Enum. I have an interface, Identifiable (specifying one method: identify), that allows me to specify how any object identifies itself to my application for searching purposes. This interface enables me to scan lists of any type of objects (whichever field the object may use for identity) for an identity match.

I'd like to find a match for an identity value in my ComboBox list. In order to use this capability on my ComboBox containing the Enum values, I must be able to implement the Identifiable interface in my Enum (which, as it happens, is trivial to implement in the case of an Enum).

Why use the INCLUDE clause when creating an index?

An additional consideraion that I have not seen in the answers already given, is that included columns can be of data types that are not allowed as index key columns, such as varchar(max).

This allows you to include such columns in a covering index. I recently had to do this to provide a nHibernate generated query, which had a lot of columns in the SELECT, with a useful index.

SSL Proxy/Charles and Android trouble

for the Android7

refer to: How to get charles proxy work with Android 7 nougat?

for the Android version below Android7

From your computer, run Charles:

Open Proxy Settings: Proxy -> Proxy Settings, Proxies Tab, check "Enable transparent HTTP proxying", and remember "Port" in heart.
SSL Proxy Settings:Proxy -> SSL Proxy Settings, SSL Proxying tab, Check “enable SSL Proxying”, and add . to Locations:
Open Access Control Settings: Proxy -> Access Control Settings. Add your local subnet to authorize machines on you local network to use the proxy from another machine/mobile.

In Android Phone:

Configure your mobile: Go to Settings -> Wireless & networks -> WiFi -> Connect or modify your network, fill in the computer IP address and Port(8888):
Get Charles SSL Certificate. Visit this url from your mobile browser: http://charlesproxy.com/getssl
In “Name the certificate” enter whatever you want
Accept the security warning and install the certificate. If you install it successful, then you probably see sth like that: In your phone, Settings -> Security -> Trusted credentials:

Done.

then you can have some test on your mobile, the encrypted https request will be shown in Charles:

Error : getaddrinfo ENOTFOUND registry.npmjs.org registry.npmjs.org:443

npm config set registry https://registry.npmjs.org/

this is the only solution for me.

TypeError: expected a character buffer object - while trying to save integer to textfile

from __future__ import with_statement
with open('file.txt','r+') as f:
    counter = str(int(f.read().strip())+1)
    f.seek(0)
    f.write(counter)

Cordova app not displaying correctly on iPhone X (Simulator)

I found the solution to the white bars here:

Set viewport-fit=cover on the viewport <meta> tag, i.e.:

<meta name="viewport" content="initial-scale=1, width=device-width, height=device-height, viewport-fit=cover">

The white bars in UIWebView then disappear:

The solution to remove the black areas (provided by @dpogue in a comment below) is to use LaunchStoryboard images with cordova-plugin-splashscreen to replace the legacy launch images, used by Cordova by default. To do so, add the following to the iOS platform in config.xml:

<platform name="ios">    
    <splash src="res/screen/ios/Default@2x~iphone~anyany.png" />
    <splash src="res/screen/ios/Default@2x~iphone~comany.png" />
    <splash src="res/screen/ios/Default@2x~iphone~comcom.png" />
    <splash src="res/screen/ios/Default@3x~iphone~anyany.png" />
    <splash src="res/screen/ios/Default@3x~iphone~anycom.png" />
    <splash src="res/screen/ios/Default@3x~iphone~comany.png" />
    <splash src="res/screen/ios/Default@2x~ipad~anyany.png" />
    <splash src="res/screen/ios/Default@2x~ipad~comany.png" />   

    <!-- more iOS config... -->
</platform>

Then create the images with the following dimensions in res/screen/ios (remove any existing ones):

Default@2x~iphone~anyany.png - 1334x1334
Default@2x~iphone~comany.png - 750x1334
Default@2x~iphone~comcom.png - 1334x750
Default@3x~iphone~anyany.png - 2208x2208
Default@3x~iphone~anycom.png - 2208x1242
Default@3x~iphone~comany.png - 1242x2208
Default@2x~ipad~anyany.png - 2732x2732
Default@2x~ipad~comany.png - 1278x2732

Once the black bars are removed, there's another thing that's different about the iPhone X to address: The status bar is larger than 20px due to the "notch", which means any content at the far top of your Cordova app will be obscured by it:

Rather than hard-coding a padding in pixels, you can handle this automatically in CSS using the new safe-area-inset-* constants in iOS 11.

Note: in iOS 11.0 the function to handle these constants was called constant() but in iOS 11.2 Apple renamed it to env() (see here), therefore to cover both cases you need to overload the CSS rule with both and rely on the CSS fallback mechanism to apply the appropriate one:

body{
    padding-top: constant(safe-area-inset-top);
    padding-top: env(safe-area-inset-top);
}

The result is then as desired: the app content covers the full screen, but is not obscured by the "notch":

I've created a Cordova test project which illustrates the above steps: webview-test.zip

Notes:

Footer buttons

If your app has footer buttons (as mine does), you will also need to apply safe-area-inset-bottom to avoid them being overlapped by the virtual Home button on iPhone X.
In my case, I couldn't apply this to <body> as the footer is absolutely positioned, so I needed to apply it directly to the footer:

.toolbar-footer{
    margin-bottom: constant(safe-area-inset-bottom);
    margin-bottom: env(safe-area-inset-bottom);
}

cordova-plugin-statusbar

The status bar size has changed on iPhone X, so older versions of cordova-plugin-statusbar display incorrectly on iPhone X
Mike Hartington has created this pull request which applies the necessary changes.
This was merged into the [email protected] release, so make sure you're using at least this version to apply to safe-area-insets

splashscreen

The LaunchScreen storyboard constraints changed on iOS 11/iPhone X, meaning the splashscreen appeared to "jump" on launch when using existing versions of the plugin (see here).
This was captured in bug report CB-13505, fixed PR cordova-ios#354 and released in [email protected], so make sure you're using a recent version of the cordova-ios platform.

device orientation

When using UIWebView on iOS 11.0, rotating from portrait > landscape > portrait causes the safe-area-inset not to be re-applied, causing the content to be obscured by the notch again (as highlighted by jms in a comment below).
Also happens if app is launched in landscape then rotated to portrait
This doesn't happen when using WKWebView via cordova-plugin-wkwebview-engine.
Radar report: http://www.openradar.me/radar?id=5035192880201728
Update: this appears to have been fixed in iOS 11.1

For reference, this is the original Cordova issue I opened which captures this: https://issues.apache.org/jira/browse/CB-13273

Get root view from current activity

In Kotlin we can do it a little shorter:

val rootView = window.decorView.rootView

#pragma once vs include guards?

Atop explanation by Konrad Kleine above.

A brief summary:

when we use # pragma once it is much of the compiler responsibility, not to allow its inclusion more than once. Which means, after you mention the code-snippet in the file, it is no more your responsibility.

Now, compiler looks, for this code-snippet at the beginning of the file, and skips it from being included (if already included once). This definitely will reduce the compilation-time (on an average and in huge-system). However, in case of mocks/test environment, will make the test-cases implementation difficult, due to circular etc dependencies.

Now, when we use the #ifndef XYZ_H for the headers, it is more of the developers responsibility to maintain the dependency of headers. Which means, whenever due to some new header file, there is possibility of the circular dependency, compiler will just flag some "undefined .." error messages at compile time, and it is user to check the logical connection/flow of the entities and rectify the improper includes.

This definitely will add to the compilation time (as needs to rectified and re-run). Also, as it works on the basis of including the file, based on the "XYZ_H" defined-state, and still complains, if not able to get all the definitions.

Therefore, to avoid situations like this, we should use, as;

#pragma once
#ifndef XYZ_H
#define XYZ_H
...
#endif

i.e. the combination of both.

Create html documentation for C# code

This page might interest you: http://msdn.microsoft.com/en-us/magazine/dd722812.aspx

You can generate the XML documentation file using either the command-line compiler or through the Visual Studio interface. If you are compiling with the command-line compiler, use options /doc or /doc+. That will generate an XML file by the same name and in the same path as the assembly. To specify a different file name, use /doc:file.

If you are using the Visual Studio interface, there's a setting that controls whether the XML documentation file is generated. To set it, double-click My Project in Solution Explorer to open the Project Designer. Navigate to the Compile tab. Find "Generate XML documentation file" at the bottom of the window, and make sure it is checked. By default this setting is on. It generates an XML file using the same name and path as the assembly.

not:first-child selector

Since :not is not accepted by IE6-8, I would suggest you this:

div ul:nth-child(n+2) {
    background-color: #900;
}

So you pick every ul in its parent element except the first one.

Refer to Chris Coyer's "Useful :nth-child Recipes" article for more nth-child examples.

Setting state on componentDidMount()

It is not an anti-pattern to call setState in componentDidMount. In fact, ReactJS provides an example of this in their documentation:

You should populate data with AJAX calls in the componentDidMount lifecycle method. This is so you can use setState to update your component when the data is retrieved.

Example From Doc

componentDidMount() {
    fetch("https://api.example.com/items")
      .then(res => res.json())
      .then(
        (result) => {
          this.setState({
            isLoaded: true,
            items: result.items
          });
        },
        // Note: it's important to handle errors here
        // instead of a catch() block so that we don't swallow
        // exceptions from actual bugs in components.
        (error) => {
          this.setState({
            isLoaded: true,
            error
          });
        }
      )
  }

get current date with 'yyyy-MM-dd' format in Angular 4

Try this:

   import * as moment from 'moment';

     ngOnInit() {
     this.date = moment().format("YYYY Do MMM");
                }

Address already in use: JVM_Bind java

The quick answer on how to prevent it is that you most likely need to stop JBoss before starting it again.

You should be able to call the "Terminate" button in the Console view to shutdown the server.

How to commit to remote git repository

Have you tried git push? gitref.org has a nice section dealing with remote repositories.

You can also get help from the command line using the --help option. For example:

% git push --help
GIT-PUSH(1)                             Git Manual                             GIT-PUSH(1)



NAME
       git-push - Update remote refs along with associated objects

SYNOPSIS
       git push [--all | --mirror | --tags] [-n | --dry-run] [--receive-pack=<git-receive-pack>]
                  [--repo=<repository>] [-f | --force] [-v | --verbose] [-u | --set-upstream]
                  [<repository> [<refspec>...]]
...

What do I do when my program crashes with exception 0xc0000005 at address 0?

Problems with the stack frames could indicate stack corruption (a truely horrible beast), optimisation, or mixing frameworks such as C/C++/C#/Delphi and other craziness as that - there is no absolute standard with respect to stack frames. (Some languages do not even have them!).

So, I suggest getting slightly annoyed with the stack frame issues, ignoring it, and then just use Remy's answer.

How can I manually set an Angular form field as invalid?

In my Reactive form, I needed to mark a field as invalid if another field was checked. In ng version 7 I did the following:

    const checkboxField = this.form.get('<name of field>');
    const dropDownField = this.form.get('<name of field>');

    this.checkboxField$ = checkboxField.valueChanges
        .subscribe((checked: boolean) => {
            if(checked) {
                dropDownField.setValidators(Validators.required);
                dropDownField.setErrors({ required: true });
                dropDownField.markAsDirty();
            } else {
                dropDownField.clearValidators();
                dropDownField.markAsPristine();
            }
        });

So above, when I check the box it sets the dropdown as required and marks it as dirty. If you don't mark as such it then it won't be invalid (in error) until you try to submit the form or interact with it.

If the checkbox is set to false (unchecked) then we clear the required validator on the dropdown and reset it to a pristine state.

Also - remember to unsubscribe from monitoring field changes!

What is an OS kernel ? How does it differ from an operating system?

The kernel might be the operating system or it might be a part of the operating system. In Linux, the kernel is loaded and executed first. Then it starts up other bits of the OS (like init) to make the system useful.

This is especially true in a micro-kernel environment. The kernel has minimal functionality. Everything else, like file systems and TCP/IP, run as a user process.

set date in input type date

Your code would have worked if it had been in this format: YYYY-MM-DD, this is the computer standard for date formats http://en.wikipedia.org/wiki/ISO_8601

jQuery: what is the best way to restrict "number"-only input for textboxes? (allow decimal points)

You dont see alphabets magical appearance and disappearance on key down. This works on mouse paste too.

$('#txtInt').bind('input propertychange', function () {
    $(this).val($(this).val().replace(/[^0-9]/g, ''));
});

The filename, directory name, or volume label syntax is incorrect inside batch

set myPATH="C:\Users\DEB\Downloads\10.1.1.0.4"
cd %myPATH%

The single quotes do not indicate a string, they make it starts: 'C:\ instead of C:\ so
%name% is the usual syntax for expanding a variable, the !name! syntax needs to be enabled using the command setlocal ENABLEDELAYEDEXPANSION first, or by running the command prompt with CMD /V:ON.
Don't use PATH as your name, it is a system name that contains all the locations of executable programs. If you overwrite it, random bits of your script will stop working. If you intend to change it, you need to do set PATH=%PATH%;C:\Users\DEB\Downloads\10.1.1.0.4 to keep the current PATH content, and add something to the end.

Getting SyntaxError for print with keyword argument end=' '

Compatible with both Python 2 & 3:

sys.stdout.write('mytext')

Compatible with only Python 2

print 'mytext',

Compatible with only Python 3

print('mytext', end='')

How to retrieve form values from HTTPPOST, dictionary or?

You could have your controller action take an object which would reflect the form input names and the default model binder will automatically create this object for you:

[HttpPost]
public ActionResult SubmitAction(SomeModel model)
{
    var value1 = model.SimpleProp1;
    var value2 = model.SimpleProp2;
    var value3 = model.ComplexProp1.SimpleProp1;
    ...

    ... return something ...
}

Another (obviously uglier) way is:

[HttpPost]
public ActionResult SubmitAction()
{
    var value1 = Request["SimpleProp1"];
    var value2 = Request["SimpleProp2"];
    var value3 = Request["ComplexProp1.SimpleProp1"];
    ...

    ... return something ...
}

How to ssh from within a bash script?

If you want the password prompt to go away then use key based authentication (described here).
To run commands remotely over ssh you have to give them as an argument to ssh, like the following:

root@host:~ # ssh root@www 'ps -ef | grep apache | grep -v grep | wc -l'

Insert multiple values using INSERT INTO (SQL Server 2005)

You can also use the following syntax:-

INSERT INTO MyTable (FirstCol, SecondCol)
SELECT 'First' ,1
UNION ALL
SELECT 'Second' ,2
UNION ALL
SELECT 'Third' ,3
UNION ALL
SELECT 'Fourth' ,4
UNION ALL
SELECT 'Fifth' ,5
GO

From here

How to encrypt and decrypt file in Android?

Use a CipherOutputStream or CipherInputStream with a Cipher and your FileInputStream / FileOutputStream.

I would suggest something like Cipher.getInstance("AES/CBC/PKCS5Padding") for creating the Cipher class. CBC mode is secure and does not have the vulnerabilities of ECB mode for non-random plaintexts. It should be present in any generic cryptographic library, ensuring high compatibility.

Don't forget to use a Initialization Vector (IV) generated by a secure random generator if you want to encrypt multiple files with the same key. You can prefix the plain IV at the start of the ciphertext. It is always exactly one block (16 bytes) in size.

If you want to use a password, please make sure you do use a good key derivation mechanism (look up password based encryption or password based key derivation). PBKDF2 is the most commonly used Password Based Key Derivation scheme and it is present in most Java runtimes, including Android. Note that SHA-1 is a bit outdated hash function, but it should be fine in PBKDF2, and does currently present the most compatible option.

Always specify the character encoding when encoding/decoding strings, or you'll be in trouble when the platform encoding differs from the previous one. In other words, don't use String.getBytes() but use String.getBytes(StandardCharsets.UTF_8).

To make it more secure, please add cryptographic integrity and authenticity by adding a secure checksum (MAC or HMAC) over the ciphertext and IV, preferably using a different key. Without an authentication tag the ciphertext may be changed in such a way that the change cannot be detected.

Be warned that CipherInputStream may not report BadPaddingException, this includes BadPaddingException generated for authenticated ciphers such as GCM. This would make the streams incompatible and insecure for these kind of authenticated ciphers.

What's the difference between "2*2" and "2**2" in Python?

The ** operator in Python is really "power;" that is, 2**3 = 8.

How to uninstall Golang?

On linux we can do like this to remove go completely:

rm -rf "/usr/local/.go/"
rm -rf "/usr/local/go/"

These two command remove go and hidden .go files. Now we also have to update entries in shell profile.

Open your basic file. Mostly I open like this sudo gedit ~/.bashrc and remove all go mentions.

You can also do by sed command in ubuntu

sed -i '/# GoLang/d' .bashrc
sed -i '/export GOROOT/d' .bashrc
sed -i '/:$GOROOT/d' .bashrc
sed -i '/export GOPATH/d' .bashrc
sed -i '/:$GOPATH/d' .bashrc

It will remove Golang from everywhere. Also run this after running these command

source ~/.bash_profile

Tested on linux 18.04 also. That's All.

Ruby, remove last N characters from a string?

Using regex:

str = 'string'
n = 2  #to remove last n characters

str[/\A.{#{str.size-n}}/] #=> "stri"

Float a DIV on top of another DIV

I know this post is little bit old but here is a potential solution for anyone who has the same problem:

First, I would change the CSS display for #popup to "none" instead of "hidden".

Second, I would change the HTML as follow:

<div id="overlay-back"></div>
<div id="popup">
    <div style="position: relative;">
        <img class="close-image" src="images/closebtn.png" />
        <span><img src="images/load_sign.png" width="400" height="566" /></span>
    </div>            
</div>

And for Style as follow:

.close-image
{
   display: block;
   float: right;
   cursor: pointer;
   z-index: 3;
   position: absolute;
   right: 0;
   top: 0;
}

I got this idea from this website (kessitek.com). A very good example on how to position elements,:

How to position a div on top of another div

I hope this helps,

Zag,

How to get first N elements of a list in C#?

var firstFiveItems = myList.Take(5);

Or to slice:

var secondFiveItems = myList.Skip(5).Take(5);

And of course often it's convenient to get the first five items according to some kind of order:

var firstFiveArrivals = myList.OrderBy(i => i.ArrivalTime).Take(5);

Press enter in textbox to and execute button command

Since everybody covered the KeyDown answers, how about using the IsDefault on the button?

You can read this tip for a quick howto and what it does: http://www.codeproject.com/Tips/665886/Button-Tip-IsDefault-IsCancel-and-other-usability

Here's an example from the article linked:

<Button IsDefault = "true" 
        Click     = "SaveClicked"
        Content   = "Save"  ... />
'''

Order columns through Bootstrap4

I'm using Bootstrap 3, so i don't know if there is an easier way to do it Bootstrap 4 but this css should work for you:

.pull-right-xs {
    float: right;
}

@media (min-width: 768px) {
   .pull-right-xs {
      float: left;
   }
}

...and add class to second column:

<div class="row">
    <div class="col-xs-3 col-md-6">
        1
    </div>
    <div class="col-xs-3 col-md-6 pull-right-xs">
        2
    </div>
    <div class="col-xs-6 col-md-12">
        3
    </div>
</div>

EDIT:

Ohh... it looks like what i was writen above is exacly a .pull-xs-right class in Bootstrap 4 :X Just add it to second column and it should work perfectly.

vuetify center items into v-flex

<v-layout justify-center>
  <v-card-actions>
    <v-btn primary>
     <span>SignUp</span>
    </v-btn>`enter code here`
  </v-card-actions>
</v-layout>

How to get the error message from the error code returned by GetLastError()?

GetLastError returns a numerical error code. To obtain a descriptive error message (e.g., to display to a user), you can call FormatMessage:

// This functions fills a caller-defined character buffer (pBuffer)
// of max length (cchBufferLength) with the human-readable error message
// for a Win32 error code (dwErrorCode).
// 
// Returns TRUE if successful, or FALSE otherwise.
// If successful, pBuffer is guaranteed to be NUL-terminated.
// On failure, the contents of pBuffer are undefined.
BOOL GetErrorMessage(DWORD dwErrorCode, LPTSTR pBuffer, DWORD cchBufferLength)
{
    if (cchBufferLength == 0)
    {
        return FALSE;
    }

    DWORD cchMsg = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
                                 NULL,  /* (not used with FORMAT_MESSAGE_FROM_SYSTEM) */
                                 dwErrorCode,
                                 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                                 pBuffer,
                                 cchBufferLength,
                                 NULL);
    return (cchMsg > 0);
}

In C++, you can simplify the interface considerably by using the std::string class:

#include <Windows.h>
#include <system_error>
#include <memory>
#include <string>
typedef std::basic_string<TCHAR> String;

String GetErrorMessage(DWORD dwErrorCode)
{
    LPTSTR psz{ nullptr };
    const DWORD cchMsg = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM
                                         | FORMAT_MESSAGE_IGNORE_INSERTS
                                         | FORMAT_MESSAGE_ALLOCATE_BUFFER,
                                       NULL, // (not used with FORMAT_MESSAGE_FROM_SYSTEM)
                                       dwErrorCode,
                                       MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                                       reinterpret_cast<LPTSTR>(&psz),
                                       0,
                                       NULL);
    if (cchMsg > 0)
    {
        // Assign buffer to smart pointer with custom deleter so that memory gets released
        // in case String's c'tor throws an exception.
        auto deleter = [](void* p) { ::LocalFree(p); };
        std::unique_ptr<TCHAR, decltype(deleter)> ptrBuffer(psz, deleter);
        return String(ptrBuffer.get(), cchMsg);
    }
    else
    {
        auto error_code{ ::GetLastError() };
        throw std::system_error( error_code, std::system_category(),
                                 "Failed to retrieve error message string.");
    }
}

NOTE: These functions also work for HRESULT values. Just change the first parameter from DWORD dwErrorCode to HRESULT hResult. The rest of the code can remain unchanged.

These implementations provide the following improvements over the existing answers:

Complete sample code, not just a reference to the API to call.
Provides both C and C++ implementations.
Works for both Unicode and MBCS project settings.
Takes the error code as an input parameter. This is important, as a thread's last error code is only valid at well defined points. An input parameter allows the caller to follow the documented contract.
Implements proper exception safety. Unlike all of the other solutions that implicitly use exceptions, this implementation will not leak memory in case an exception is thrown while constructing the return value.
Proper use of the FORMAT_MESSAGE_IGNORE_INSERTS flag. See The importance of the FORMAT_MESSAGE_IGNORE_INSERTS flag for more information.
Proper error handling/error reporting, unlike some of the other answers, that silently ignore errors.

This answer has been incorporated from Stack Overflow Documentation. The following users have contributed to the example: stackptr, Ajay, Cody Gray?, IInspectable.

How do I perform query filtering in django templates

You can't do this, which is by design. The Django framework authors intended a strict separation of presentation code from data logic. Filtering models is data logic, and outputting HTML is presentation logic.

So you have several options. The easiest is to do the filtering, then pass the result to render_to_response. Or you could write a method in your model so that you can say {% for object in data.filtered_set %}. Finally, you could write your own template tag, although in this specific case I would advise against that.

How to succinctly write a formula with many variables from a data frame?

A slightly different approach is to create your formula from a string. In the formula help page you will find the following example :

## Create a formula for a model with a large number of variables:
xnam <- paste("x", 1:25, sep="")
fmla <- as.formula(paste("y ~ ", paste(xnam, collapse= "+")))

Then if you look at the generated formula, you will get :

R> fmla
y ~ x1 + x2 + x3 + x4 + x5 + x6 + x7 + x8 + x9 + x10 + x11 + 
    x12 + x13 + x14 + x15 + x16 + x17 + x18 + x19 + x20 + x21 + 
    x22 + x23 + x24 + x25

ImportError: No module named PytQt5

After getting the help from @Blender, @ekhumoro and @Dan, I understand the Linux and Python more than before. Thank you. I got the an idea by @ekhumoro, it is I didn't install PyQt5 correctly. So I delete PyQt5 folder and download again. And redo everything from very start.

After redoing, I got the error as my last update at my question. So, when I search at stack, I got the following solution from here

sudo ln -s /usr/include/python2.7 /usr/local/include/python2.7

And then, I did "sudo make" and "sudo make install" step by step. After "sudo make install", I got the following error. But I ignored it and I created a simple design with qt designer. And I converted it into python file by pyuic5. Everything are going well.

install -m 755 -p /home/thura/PyQt/pyuic5 /usr/bin/
strip /usr/bin/pyuic5
strip:/usr/bin/pyuic5: File format not recognized
make: [install_pyuic5] Error 1 (ignored)

don't fail jenkins build if execute shell fails

Jenkins determines the success/failure of a step by the return value of the step. For the case of a shell, it should be the return of the last value. For both Windows CMD and (POSIX) Bash shells, you should be able to set the return value manually by using exit 0 as the last command.

Wavy shape with css

My implementation uses the svg element in html and I also made a generator for making the wave you want:

https://smooth.ie/blogs/news/svg-wavey-transitions-between-sections

<div style="height: 150px; overflow: hidden;">
  <svg viewBox="0 0 500 150" preserveAspectRatio="none" style="height: 100%; width: 100%;">
    <path d="M0.00,92.27 C216.83,192.92 304.30,8.39 500.00,109.03 L500.00,0.00 L0.00,0.00 Z" style="stroke: none;fill: #e1efe3;"></path>
  </svg>
</div>

https://jsfiddle.net/1b8L7nax/5/

What is the use of adding a null key or value to a HashMap in Java?

A null key can also be helpful when the map stores data for UI selections where the map key represents a bean field.

A corresponding null field value would for example be represented as "(please select)" in the UI selection.

How to create a HashMap with two keys (Key-Pair, Value)?

When you create your own key pair object, you should face a few thing.

First, you should be aware of implementing hashCode() and equals(). You will need to do this.

Second, when implementing hashCode(), make sure you understand how it works. The given user example

public int hashCode() {
    return this.x ^ this.y;
}

is actually one of the worst implementations you can do. The reason is simple: you have a lot of equal hashes! And the hashCode() should return int values that tend to be rare, unique at it's best. Use something like this:

public int hashCode() {
  return (X << 16) + Y;
}

This is fast and returns unique hashes for keys between -2^16 and 2^16-1 (-65536 to 65535). This fits in almost any case. Very rarely you are out of this bounds.

Third, when implementing equals() also know what it is used for and be aware of how you create your keys, since they are objects. Often you do unnecessary if statements cause you will always have the same result.

If you create keys like this: map.put(new Key(x,y),V); you will never compare the references of your keys. Cause everytime you want to acces the map, you will do something like map.get(new Key(x,y));. Therefore your equals() does not need a statement like if (this == obj). It will never occure.

Instead of if (getClass() != obj.getClass()) in your equals() better use if (!(obj instanceof this)). It will be valid even for subclasses.

So the only thing you need to compare is actually X and Y. So the best equals() implementation in this case would be:

public boolean equals (final Object O) {
  if (!(O instanceof Key)) return false;
  if (((Key) O).X != X) return false;
  if (((Key) O).Y != Y) return false;
  return true;
}

So in the end your key class is like this:

public class Key {

  public final int X;
  public final int Y;

  public Key(final int X, final int Y) {
    this.X = X;
    this.Y = Y;
  }

  public boolean equals (final Object O) {
    if (!(O instanceof Key)) return false;
    if (((Key) O).X != X) return false;
    if (((Key) O).Y != Y) return false;
    return true;
  }

  public int hashCode() {
    return (X << 16) + Y;
  }

}

You can give your dimension indices X and Y a public access level, due to the fact they are final and do not contain sensitive information. I'm not a 100% sure whether private access level works correctly in any case when casting the Object to a Key.

If you wonder about the finals, I declare anything as final which value is set on instancing and never changes - and therefore is an object constant.

AngularJS ng-repeat handle empty list case

You can use ngShow.

<li ng-show="!events.length">No events</li>

See example.

Or you can use ngHide

<li ng-hide="events.length">No events</li>

See example.

For object you can test Object.keys.

SVG Positioning

I know this is old but neither an <svg> group tag nor a <g> fixed the issue I was facing. I needed to adjust the y position of a tag which also had animation on it.

The solution was to use both the and tag together:

<svg y="1190" x="235">
   <g class="light-1">
     <path />
   </g>
</svg>

Create HTML table using Javascript

The problem is that if you try to write a <table> or a <tr> or <td> tag using JS every time you insert a new tag the browser will try to close it as it will think that there is an error on the code.

Instead of writing your table line by line, concatenate your table into a variable and insert it once created:

<script language="javascript" type="text/javascript">
<!--

var myArray    = new Array();
    myArray[0] = 1;
    myArray[1] = 2.218;
    myArray[2] = 33;
    myArray[3] = 114.94;
    myArray[4] = 5;
    myArray[5] = 33;
    myArray[6] = 114.980;
    myArray[7] = 5;

    var myTable= "<table><tr><td style='width: 100px; color: red;'>Col Head 1</td>";
    myTable+= "<td style='width: 100px; color: red; text-align: right;'>Col Head 2</td>";
    myTable+="<td style='width: 100px; color: red; text-align: right;'>Col Head 3</td></tr>";

    myTable+="<tr><td style='width: 100px;                   '>---------------</td>";
    myTable+="<td     style='width: 100px; text-align: right;'>---------------</td>";
    myTable+="<td     style='width: 100px; text-align: right;'>---------------</td></tr>";

  for (var i=0; i<8; i++) {
    myTable+="<tr><td style='width: 100px;'>Number " + i + " is:</td>";
    myArray[i] = myArray[i].toFixed(3);
    myTable+="<td style='width: 100px; text-align: right;'>" + myArray[i] + "</td>";
    myTable+="<td style='width: 100px; text-align: right;'>" + myArray[i] + "</td></tr>";
  }  
   myTable+="</table>";

 document.write( myTable);

//-->
</script>

If your code is in an external JS file, in HTML create an element with an ID where you want your table to appear:

<div id="tablePrint"> </div>

And in JS instead of document.write(myTable) use the following code:

document.getElementById('tablePrint').innerHTML = myTable;

Hiding the address bar of a browser (popup)

Looking for the same, the only thing I'm able to do is

Launch Google Chrome in app mode

Chrome.exe --app="<address>"

From the run prompt. Example:

Chrome.exe --app="http://www.google.com"

Hide the address bar in Mozilla Firefox

Type about:config in the address bar, the search for:

dom.disable_window_open_feature.location

And set it to false

So, when you open a popup window, it will launch with the address bar hidden. For example:

window.open("http://www.google.com",'','postwindow');

Now, I'm looking to do something similar with Microsoft Edge, I have not found anything yet for this browser.

How do I exit the Vim editor?

If you want to quit without saving in Vim and have Vim return a non-zero exit code, you can use :cq.

I use this all the time because I can't be bothered to pinky shift for !. I often pipe things to Vim which don't need to be saved in a file. We also have an odd SVN wrapper at work which must be exited with a non-zero value in order to abort a checkin.

Python Remove last char from string and return it

The precise wording of the question makes me think it's impossible.

return to me means you have a function, which you have passed a string as a parameter.

You cannot change this parameter. Assigning to it will only change the value of the parameter within the function, not the passed in string. E.g.

>>> def removeAndReturnLastCharacter(a):
        c = a[-1]
        a = a[:-1]
        return c

>>> b = "Hello, Gaukler!"
>>> removeAndReturnLastCharacter(b)
!

>>> b    # b has not been changed
Hello, Gaukler!

String to Binary in C#

It sounds like you basically want to take an ASCII string, or more preferably, a byte[] (as you can encode your string to a byte[] using your preferred encoding mode) into a string of ones and zeros? i.e. 101010010010100100100101001010010100101001010010101000010111101101010

This will do that for you...

//Formats a byte[] into a binary string (010010010010100101010)
public string Format(byte[] data)
{
    //storage for the resulting string
    string result = string.Empty;
    //iterate through the byte[]
    foreach(byte value in data)
    {
        //storage for the individual byte
        string binarybyte = Convert.ToString(value, 2);
        //if the binarybyte is not 8 characters long, its not a proper result
        while(binarybyte.Length < 8)
        {
            //prepend the value with a 0
            binarybyte = "0" + binarybyte;
        }
        //append the binarybyte to the result
        result += binarybyte;
    }
    //return the result
    return result;
}

Calling another different view from the controller using ASP.NET MVC 4

To return a different view, you can specify the name of the view you want to return and model as follows:

return View("ViewName", yourModel);

if the view is in different folder under Views folder then use below absolute path:

return View("~/Views/FolderName/ViewName.aspx");

How can you search Google Programmatically Java API

Some facts:

Google offers a public search webservice API which returns JSON: http://ajax.googleapis.com/ajax/services/search/web. Documentation here
Java offers java.net.URL and java.net.URLConnection to fire and handle HTTP requests.
JSON can in Java be converted to a fullworthy Javabean object using an arbitrary Java JSON API. One of the best is Google Gson.

Now do the math:

public static void main(String[] args) throws Exception {
    String google = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&q=";
    String search = "stackoverflow";
    String charset = "UTF-8";
    
    URL url = new URL(google + URLEncoder.encode(search, charset));
    Reader reader = new InputStreamReader(url.openStream(), charset);
    GoogleResults results = new Gson().fromJson(reader, GoogleResults.class);
    
    // Show title and URL of 1st result.
    System.out.println(results.getResponseData().getResults().get(0).getTitle());
    System.out.println(results.getResponseData().getResults().get(0).getUrl());
}

With this Javabean class representing the most important JSON data as returned by Google (it actually returns more data, but it's left up to you as an exercise to expand this Javabean code accordingly):

public class GoogleResults {

    private ResponseData responseData;
    public ResponseData getResponseData() { return responseData; }
    public void setResponseData(ResponseData responseData) { this.responseData = responseData; }
    public String toString() { return "ResponseData[" + responseData + "]"; }

    static class ResponseData {
        private List<Result> results;
        public List<Result> getResults() { return results; }
        public void setResults(List<Result> results) { this.results = results; }
        public String toString() { return "Results[" + results + "]"; }
    }

    static class Result {
        private String url;
        private String title;
        public String getUrl() { return url; }
        public String getTitle() { return title; }
        public void setUrl(String url) { this.url = url; }
        public void setTitle(String title) { this.title = title; }
        public String toString() { return "Result[url:" + url +",title:" + title + "]"; }
    }

}

###See also:

Update since November 2010 (2 months after the above answer), the public search webservice has become deprecated (and the last day on which the service was offered was September 29, 2014). Your best bet is now querying http://www.google.com/search directly along with a honest user agent and then parse the result using a HTML parser. If you omit the user agent, then you get a 403 back. If you're lying in the user agent and simulate a web browser (e.g. Chrome or Firefox), then you get a way much larger HTML response back which is a waste of bandwidth and performance.

Here's a kickoff example using Jsoup as HTML parser:

String google = "http://www.google.com/search?q=";
String search = "stackoverflow";
String charset = "UTF-8";
String userAgent = "ExampleBot 1.0 (+http://example.com/bot)"; // Change this to your company's name and bot homepage!

Elements links = Jsoup.connect(google + URLEncoder.encode(search, charset)).userAgent(userAgent).get().select(".g>.r>a");

for (Element link : links) {
    String title = link.text();
    String url = link.absUrl("href"); // Google returns URLs in format "http://www.google.com/url?q=<url>&sa=U&ei=<someKey>".
    url = URLDecoder.decode(url.substring(url.indexOf('=') + 1, url.indexOf('&')), "UTF-8");
    
    if (!url.startsWith("http")) {
        continue; // Ads/news/etc.
    }
    
    System.out.println("Title: " + title);
    System.out.println("URL: " + url);
}

Is a Java hashmap search really O(1)?

We've established that the standard description of hash table lookups being O(1) refers to the average-case expected time, not the strict worst-case performance. For a hash table resolving collisions with chaining (like Java's hashmap) this is technically O(1+a) with a good hash function, where a is the table's load factor. Still constant as long as the number of objects you're storing is no more than a constant factor larger than the table size.

It's also been explained that strictly speaking it's possible to construct input that requires O(n) lookups for any deterministic hash function. But it's also interesting to consider the worst-case expected time, which is different than average search time. Using chaining this is O(1 + the length of the longest chain), for example T(log n / log log n) when a=1.

If you're interested in theoretical ways to achieve constant time expected worst-case lookups, you can read about dynamic perfect hashing which resolves collisions recursively with another hash table!

HTML for the Pause symbol in audio and video control

I found it, it’s in the Miscellaneous Technical block. ? (U+23F8)

Sequence contains no elements?

Please use

.FirstOrDefault()

because if in the first row of the result there is no info this instruction goes to the default info.

How can I display a list view in an Android Alert Dialog?

You can use a custom dialog.

Custom dialog layout. list.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android" 
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
    <ListView
        android:id="@+id/lv"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"/>
</LinearLayout>

In your activity

Dialog dialog = new Dialog(Activity.this);
       dialog.setContentView(R.layout.list)

ListView lv = (ListView ) dialog.findViewById(R.id.lv);
dialog.setCancelable(true);
dialog.setTitle("ListView");
dialog.show();

Edit:

Using alertdialog

String names[] ={"A","B","C","D"};
AlertDialog.Builder alertDialog = new AlertDialog.Builder(MainActivity.this);
LayoutInflater inflater = getLayoutInflater();
View convertView = (View) inflater.inflate(R.layout.custom, null);
alertDialog.setView(convertView);
alertDialog.setTitle("List");
ListView lv = (ListView) convertView.findViewById(R.id.lv);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,names);
lv.setAdapter(adapter);
alertDialog.show();

custom.xml

<?xml version="1.0" encoding="utf-8"?>
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/listView1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

</ListView>

Snap

enter image description here

Generate random string/characters in JavaScript

Generate any number of hexadecimal character (e.g. 32):

(function(max){let r='';for(let i=0;i<max/13;i++)r+=(Math.random()+1).toString(16).substring(2);return r.substring(0,max).toUpperCase()})(32);

Remove Server Response Header IIS7

In IIS 10, we use a similar solution to Drew's approach, i.e.:

using System;
using System.Web;

namespace Common.Web.Modules.Http
{
    /// <summary>
    /// Sets custom headers in all requests (e.g. "Server" header) or simply remove some.
    /// </summary>
    public class CustomHeaderModule : IHttpModule
    {
        public void Init(HttpApplication context)
        {
            context.PreSendRequestHeaders += OnPreSendRequestHeaders;
        }

        public void Dispose() { }

        /// <summary>
        /// Event handler that implements the desired behavior for the PreSendRequestHeaders event,
        /// that occurs just before ASP.NET sends HTTP headers to the client.
        /// 
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void OnPreSendRequestHeaders(object sender, EventArgs e)
        {
            //HttpContext.Current.Response.Headers.Remove("Server");
            HttpContext.Current.Response.Headers.Set("Server", "MyServer");
        }
    }
}

And obviously add a reference to that dll in your project(s) and also the module in the config(s) you want:

_x000D_

<system.webServer>_x000D_
    <modules>_x000D_
      <!--Use http module to remove/customize IIS "Server" header-->_x000D_
      <add name="CustomHeaderModule" type="Common.Web.Modules.Http.CustomHeaderModule" />_x000D_
    </modules>_x000D_
</system.webServer>

_x000D_

IMPORTANT NOTE1: This solution needs an application pool set as integrated;

IMPORTANT NOTE2: All responses within the web app will be affected by this (css and js included);

php - How do I fix this illegal offset type error

check $xml->entry[$i] exists and is an object before trying to get a property of it

 if(isset($xml->entry[$i]) && is_object($xml->entry[$i])){
   $source = $xml->entry[$i]->source;          
   $s[$source] += 1;
 }

or $source might not be a legal array offset but an array, object, resource or possibly null

How to show a running progress bar while page is loading

Simple Steps, follow them and i guess it will solve your problem

Include these Css in your page,

.progress {
      position: relative;
      height: 2px;
      display: block;
      width: 100%;
      background-color: white;
      border-radius: 2px;
      background-clip: padding-box;
      /*margin: 0.5rem 0 1rem 0;*/
      overflow: hidden;

    }
    .progress .indeterminate {
background-color:black; }
    .progress .indeterminate:before {
      content: '';
      position: absolute;
      background-color: #2C67B1;
      top: 0;
      left: 0;
      bottom: 0;
      will-change: left, right;
      -webkit-animation: indeterminate 2.1s cubic-bezier(0.65, 0.815, 0.735, 0.395) infinite;
              animation: indeterminate 2.1s cubic-bezier(0.65, 0.815, 0.735, 0.395) infinite; }
    .progress .indeterminate:after {
      content: '';
      position: absolute;
      background-color: #2C67B1;
      top: 0;
      left: 0;
      bottom: 0;
      will-change: left, right;
      -webkit-animation: indeterminate-short 2.1s cubic-bezier(0.165, 0.84, 0.44, 1) infinite;
              animation: indeterminate-short 2.1s cubic-bezier(0.165, 0.84, 0.44, 1) infinite;
      -webkit-animation-delay: 1.15s;
              animation-delay: 1.15s; }

    @-webkit-keyframes indeterminate {
      0% {
        left: -35%;
        right: 100%; }
      60% {
        left: 100%;
        right: -90%; }
      100% {
        left: 100%;
        right: -90%; } }
    @keyframes indeterminate {
      0% {
        left: -35%;
        right: 100%; }
      60% {
        left: 100%;
        right: -90%; }
      100% {
        left: 100%;
        right: -90%; } }
    @-webkit-keyframes indeterminate-short {
      0% {
        left: -200%;
        right: 100%; }
      60% {
        left: 107%;
        right: -8%; }
      100% {
        left: 107%;
        right: -8%; } }
    @keyframes indeterminate-short {
      0% {
        left: -200%;
        right: 100%; }
      60% {
        left: 107%;
        right: -8%; }
      100% {
        left: 107%;
        right: -8%; } }

Then include the progress bar your body tag,

<div class="progress" id="PreLoaderBar">
        <div class="indeterminate"></div>
    </div>

then it will start as your page loads, and now what you have to do is just hide this when the page loads,or set the visibility to none, or hidden, using javascript,

document.onreadystatechange = function () {
            if (document.readyState === "complete") {
                console.log(document.readyState);
                document.getElementById("PreLoaderBar").style.display = "none";
            }
        }

Let me Know if you face any problems and also, you can add any type of progress bar you can easily find them, for this example i have used a indeterminate progress bar.

Side-by-side list items as icons within a div (css)

Here's a good resource for wrapping columned lists. http://www.communitymx.com/content/article.cfm?cid=27f87

How to display a confirmation dialog when clicking an <a> link?

This method is slightly different than either of the above answers if you attach your event handler using addEventListener (or attachEvent).

function myClickHandler(evt) {
  var allowLink = confirm('Continue with link?');
  if (!allowLink) {
    evt.returnValue = false; //for older Internet Explorer
    if (evt.preventDefault) {
      evt.preventDefault();
    }
    return false;
  }
}

You can attach this handler with either:

document.getElementById('mylinkid').addEventListener('click', myClickHandler, false);

Or for older versions of internet explorer:

document.getElementById('mylinkid').attachEvent('onclick', myClickHandler);

Add characters to a string in Javascript

It sounds like you want to use join, e.g.:

var text = list.join();

Is there a replacement for unistd.h for Windows (Visual C)?

I would recommend using mingw/msys as a development environment. Especially if you are porting simple console programs. Msys implements a Unix-like shell on Windows, and mingw is a port of the GNU compiler collection (GCC) and other GNU build tools to the Windows platform. It is an open-source project, and well-suited to the task. I currently use it to build utility programs and console applications for Windows XP, and it most certainly has that unistd.h header you are looking for.

The install procedure can be a little bit tricky, but I found that the best place to start is in MSYS.

Uncaught syntaxerror: unexpected identifier?

There are errors here :

var formTag = document.getElementsByTagName("form"), // form tag is an array
selectListItem = $('select'),
makeSelect = document.createElement('select'),
makeSelect.setAttribute("id", "groups");

The code must change to:

var formTag = document.getElementsByTagName("form");
var selectListItem = $('select');
var makeSelect = document.createElement('select');
makeSelect.setAttribute("id", "groups");

By the way, there is another error at line 129 :

var createLi.appendChild(createSubList);

Replace it with:

createLi.appendChild(createSubList);

Searching for UUIDs in text with regex

For bash:

grep -E "[a-f0-9]{8}-[a-f0-9]{4}-4[a-f0-9]{3}-[89aAbB][a-f0-9]{3}-[a-f0-9]{12}"

For example:

$> echo "f2575e6a-9bce-49e7-ae7c-bff6b555bda4" | grep -E "[a-f0-9]{8}-[a-f0-9]{4}-4[a-f0-9]{3}-[89aAbB][a-f0-9]{3}-[a-f0-9]{12}"
f2575e6a-9bce-49e7-ae7c-bff6b555bda4

Insert Picture into SQL Server 2005 Image Field using only SQL

For updating a record:

 UPDATE Employees SET [Photo] = (SELECT
 MyImage.* from Openrowset(Bulk
 'C:\photo.bmp', Single_Blob) MyImage)
 where Id = 10

Notes:

Make sure to add the 'BULKADMIN' Role Permissions for the login you are using.
Paths are not pointing to your computer when using SQL Server Management Studio. If you start SSMS on your local machine and connect to a SQL Server instance on server X, the file C:\photo.bmp will point to hard drive C: on server X, not your machine!

Webdriver Unable to connect to host 127.0.0.1 on port 7055 after 45000 ms

Installed Firefox Setup 18.0.exe it works for me

onchange equivalent in angular2

In Angular you can define event listeners like in the example below:

<!-- Here you can call public methods from parental component -->
<input (change)="method_name()">

PHP - check if variable is undefined

JavaScript's 'strict not equal' operator (!==) on comparison with undefined does not result in false on null values.

var createTouch = null;
isTouch = createTouch !== undefined  // true

To achieve an equivalent behaviour in PHP, you can check whether the variable name exists in the keys of the result of get_defined_vars().

// just to simplify output format
const BR = '<br>' . PHP_EOL;

// set a global variable to test independence in local scope
$test = 1;

// test in local scope (what is working in global scope as well)
function test()
{
  // is global variable found?
  echo '$test ' . ( array_key_exists('test', get_defined_vars())
                    ? 'exists.' : 'does not exist.' ) . BR;
  // $test does not exist.

  // is local variable found?
  $test = null;
  echo '$test ' . ( array_key_exists('test', get_defined_vars())
                    ? 'exists.' : 'does not exist.' ) . BR;
  // $test exists.

  // try same non-null variable value as globally defined as well
  $test = 1;
  echo '$test ' . ( array_key_exists('test', get_defined_vars())
                    ? 'exists.' : 'does not exist.' ) . BR;
  // $test exists.

  // repeat test after variable is unset
  unset($test);
  echo '$test ' . ( array_key_exists('test', get_defined_vars())
                    ? 'exists.' : 'does not exist.') . BR;
  // $test does not exist.
}

test();

In most cases, isset($variable) is appropriate. That is aquivalent to array_key_exists('variable', get_defined_vars()) && null !== $variable. If you just use null !== $variable without prechecking for existence, you will mess up your logs with warnings because that is an attempt to read the value of an undefined variable.

However, you can apply an undefined variable to a reference without any warning:

// write our own isset() function
function my_isset(&$var)
{
  // here $var is defined
  // and initialized to null if the given argument was not defined
  return null === $var;
}

// passing an undefined variable by reference does not log any warning
$is_set = my_isset($undefined_variable);   // $is_set is false

How to list only top level directories in Python?

This seems to work too (at least on linux):

import glob, os
glob.glob('*' + os.path.sep)

Double vs. BigDecimal?

BigDecimal is Oracle's arbitrary-precision numerical library. BigDecimal is part of the Java language and is useful for a variety of applications ranging from the financial to the scientific (that's where sort of am).

There's nothing wrong with using doubles for certain calculations. Suppose, however, you wanted to calculate Math.Pi * Math.Pi / 6, that is, the value of the Riemann Zeta Function for a real argument of two (a project I'm currently working on). Floating-point division presents you with a painful problem of rounding error.

BigDecimal, on the other hand, includes many options for calculating expressions to arbitrary precision. The add, multiply, and divide methods as described in the Oracle documentation below "take the place" of +, *, and / in BigDecimal Java World:

http://docs.oracle.com/javase/7/docs/api/java/math/BigDecimal.html

The compareTo method is especially useful in while and for loops.

Be careful, however, in your use of constructors for BigDecimal. The string constructor is very useful in many cases. For instance, the code

BigDecimal onethird = new BigDecimal("0.33333333333");

utilizes a string representation of 1/3 to represent that infinitely-repeating number to a specified degree of accuracy. The round-off error is most likely somewhere so deep inside the JVM that the round-off errors won't disturb most of your practical calculations. I have, from personal experience, seen round-off creep up, however. The setScale method is important in these regards, as can be seen from the Oracle documentation.

Excel - Combine multiple columns into one column

Function Concat(myRange As Range, Optional myDelimiter As String) As String 
  Dim r As Range 
  Application.Volatile 
  For Each r In myRange 
    If Len(r.Text) Then 
      Concat = Concat & IIf(Concat <> "", myDelimiter, "") & r.Text 
    End If 
  Next 
End Function

Are (non-void) self-closing tags valid in HTML5?

In HTML 4, <foo / (yes, with no > at all) means <foo> (which leads to <br /> meaning <br>> (i.e. <br>>) and <title/hello/ meaning <title>hello</title>). This is an SGML rule that browsers did a very poor job of supporting, and the spec advises authors to avoid the syntax.
In XHTML, <foo /> means <foo></foo>. This is an XML rule that applies to all XML documents. That said, XHTML is often served as text/html which (historically at least) gets processed by browsers using a different parser than documents served as application/xhtml+xml. The W3C provides compatibility guidelines to follow for XHTML as text/html. (Essentially: Only use self-closing tag syntax when the element is defined as EMPTY (and the end tag was forbidden in the HTML spec)).
In HTML5, the meaning of <foo /> depends on the type of element.
- On HTML elements that are designated as void elements (essentially "An element that existed before HTML5 and which was forbidden to have any content"), end tags are simply forbidden. The slash at the end of the start tag is allowed, but has no meaning. It is just syntactic sugar for people (and syntax highlighters) that are addicted to XML.
- On other HTML elements, the slash is an error, but error recovery will cause browsers to ignore it and treat the tag as a regular start tag. This will usually end up with a missing end tag causing subsequent elements to be children instead of siblings.
- Foreign elements (imported from XML applications such as SVG) treat it as self-closing syntax.

Convert boolean to int in Java

If you use Apache Commons Lang (which I think a lot of projects use it), you can just use it like this:

int myInt = BooleanUtils.toInteger(boolean_expression);

toInteger method returns 1 if boolean_expression is true, 0 otherwise

How to replace innerHTML of a div using jQuery?

Pure JS and Shortest

Pure JS

regTitle.innerHTML = 'Hello World'

_x000D_

regTitle.innerHTML = 'Hello World';

_x000D_

<div id="regTitle"></div>

_x000D_

Shortest

$(regTitle).html('Hello World');

_x000D_

// note: no quotes around regTitle_x000D_
$(regTitle).html('Hello World');

_x000D_

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
_x000D_
<div id="regTitle"></div>

_x000D_

How to style a disabled checkbox?

You can't style a disabled checkbox directly because it's controlled by the browser / OS.

However you can be clever and replace the checkbox with a label that simulates a checkbox using pure CSS. You need to have an adjacent label that you can use to style a new "pseudo checkbox". Essentially you're completely redrawing the thing but it gives you complete control over how it looks in any state.

I've thrown up a basic example so that you can see it in action: http://jsfiddle.net/JohnSReid/pr9Lx5th/3/

Here's the sample:

_x000D_

input[type="checkbox"] {_x000D_
    display: none;_x000D_
}_x000D_
_x000D_
label:before {_x000D_
    background: linear-gradient(to bottom, #fff 0px, #e6e6e6 100%) repeat scroll 0 0 rgba(0, 0, 0, 0);_x000D_
    border: 1px solid #035f8f;_x000D_
    height: 36px;_x000D_
    width: 36px;_x000D_
    display: block;_x000D_
    cursor: pointer;_x000D_
}_x000D_
input[type="checkbox"] + label:before {_x000D_
    content: '';_x000D_
    background: linear-gradient(to bottom, #e6e6e6 0px, #fff 100%) repeat scroll 0 0 rgba(0, 0, 0, 0);_x000D_
    border-color: #3d9000;_x000D_
    color: #96be0a;_x000D_
    font-size: 38px;_x000D_
    line-height: 35px;_x000D_
    text-align: center;_x000D_
}_x000D_
_x000D_
input[type="checkbox"]:disabled + label:before {_x000D_
    border-color: #eee;_x000D_
    color: #ccc;_x000D_
    background: linear-gradient(to top, #e6e6e6 0px, #fff 100%) repeat scroll 0 0 rgba(0, 0, 0, 0);_x000D_
}_x000D_
_x000D_
input[type="checkbox"]:checked + label:before {_x000D_
    content: '?';_x000D_
}

_x000D_

<div><input id="cb1" type="checkbox" disabled checked /><label for="cb1"></label></div>_x000D_
<div><input id="cb2" type="checkbox" disabled /><label for="cb2"></label></div>_x000D_
<div><input id="cb3" type="checkbox" checked /><label for="cb3"></label></div>_x000D_
<div><input id="cb4" type="checkbox" /><label for="cb4"></label></div>

_x000D_

Depending on your level of browser compatibility and accessibility, some additional tweaks will need to be made.

(XML) The markup in the document following the root element must be well-formed. Start location: 6:2

In XML there can be only one root element - you have two - heading and song.

If you restructure to something like:

<?xml version="1.0" encoding="UTF-8"?>
<song> 
 <heading>
 The Twelve Days of Christmas
 </heading>
 ....
</song>

The error about well-formed XML on the root level should disappear (though there may be other issues).

How to switch activity without animation in Android?

create your own style overriding android:Theme

<style name="noAnimationStyle" parent="android:Theme">
    <item name="android:windowAnimationStyle">@null</item>
</style>

Then use it in manifest like this:

<activity android:name=".MainActivity"
    android:theme="@style/noAnimationStyle">
</activity>

Abort a git cherry-pick?

Try also with '--quit' option, which allows you to abort the current operation and further clear the sequencer state.

--quit Forget about the current operation in progress. Can be used to clear the sequencer state after a failed cherry-pick or revert.

--abort Cancel the operation and return to the pre-sequence state.

use help to see the original doc with more details, $ git help cherry-pick

I would avoid 'git reset --hard HEAD' that is too harsh and you might ended up doing some manual work.

Get values from a listbox on a sheet

Unfortunately for MSForms list box looping through the list items and checking their Selected property is the only way. However, here is an alternative. I am storing/removing the selected item in a variable, you can do this in some remote cell and keep track of it :)

Dim StrSelection As String

Private Sub ListBox1_Change()
    If ListBox1.Selected(ListBox1.ListIndex) Then
        If StrSelection = "" Then
            StrSelection = ListBox1.List(ListBox1.ListIndex)
        Else
            StrSelection = StrSelection & "," & ListBox1.List(ListBox1.ListIndex)
        End If
    Else
        StrSelection = Replace(StrSelection, "," & ListBox1.List(ListBox1.ListIndex), "")
    End If
End Sub

Setting PHPMyAdmin Language

In config.inc.php in the top-level directory, set

$cfg['DefaultLang'] = 'en-utf-8'; // Language if no other language is recognized
// or
$cfg['Lang'] = 'en-utf-8'; // Force this language for all users

If Lang isn't set, you should be able to select the language in the initial welcome screen, and the language your browser prefers should be preselected there.

MySQL - Meaning of "PRIMARY KEY", "UNIQUE KEY" and "KEY" when used together while creating a table

Just to add to the other answers, the documentation gives this explanation:

KEY is normally a synonym for INDEX. The key attribute PRIMARY KEY can also be specified as just KEY when given in a column definition. This was implemented for compatibility with other database systems.

A UNIQUE index creates a constraint such that all values in the index must be distinct. An error occurs if you try to add a new row with a key value that matches an existing row. For all engines, a UNIQUE index permits multiple NULL values for columns that can contain NULL.

A PRIMARY KEY is a unique index where all key columns must be defined as NOT NULL. If they are not explicitly declared as NOT NULL, MySQL declares them so implicitly (and silently). A table can have only one PRIMARY KEY. The name of a PRIMARY KEY is always PRIMARY, which thus cannot be used as the name for any other kind of index.

How to count how many values per level in a given factor?

Using plyr package:

library(plyr)

count(mydf$V1)

It will return you a frequency of each value.

Can't pickle <type 'instancemethod'> when using multiprocessing Pool.map()

Some limitations though to Steven Bethard's solution :

When you register your class method as a function, the destructor of your class is surprisingly called every time your method processing is finished. So if you have 1 instance of your class that calls n times its method, members may disappear between 2 runs and you may get a message malloc: *** error for object 0x...: pointer being freed was not allocated (e.g. open member file) or pure virtual method called, terminate called without an active exception (which means than the lifetime of a member object I used was shorter than what I thought). I got this when dealing with n greater than the pool size. Here is a short example :

from multiprocessing import Pool, cpu_count
from multiprocessing.pool import ApplyResult

# --------- see Stenven's solution above -------------
from copy_reg import pickle
from types import MethodType

def _pickle_method(method):
    func_name = method.im_func.__name__
    obj = method.im_self
    cls = method.im_class
    return _unpickle_method, (func_name, obj, cls)

def _unpickle_method(func_name, obj, cls):
    for cls in cls.mro():
        try:
            func = cls.__dict__[func_name]
        except KeyError:
            pass
        else:
            break
    return func.__get__(obj, cls)


class Myclass(object):

    def __init__(self, nobj, workers=cpu_count()):

        print "Constructor ..."
        # multi-processing
        pool = Pool(processes=workers)
        async_results = [ pool.apply_async(self.process_obj, (i,)) for i in range(nobj) ]
        pool.close()
        # waiting for all results
        map(ApplyResult.wait, async_results)
        lst_results=[r.get() for r in async_results]
        print lst_results

    def __del__(self):
        print "... Destructor"

    def process_obj(self, index):
        print "object %d" % index
        return "results"

pickle(MethodType, _pickle_method, _unpickle_method)
Myclass(nobj=8, workers=3)
# problem !!! the destructor is called nobj times (instead of once)

Output:

Constructor ...
object 0
object 1
object 2
... Destructor
object 3
... Destructor
object 4
... Destructor
object 5
... Destructor
object 6
... Destructor
object 7
... Destructor
... Destructor
... Destructor
['results', 'results', 'results', 'results', 'results', 'results', 'results', 'results']
... Destructor

The __call__ method is not so equivalent, because [None,...] are read from the results :

from multiprocessing import Pool, cpu_count
from multiprocessing.pool import ApplyResult

class Myclass(object):

    def __init__(self, nobj, workers=cpu_count()):

        print "Constructor ..."
        # multiprocessing
        pool = Pool(processes=workers)
        async_results = [ pool.apply_async(self, (i,)) for i in range(nobj) ]
        pool.close()
        # waiting for all results
        map(ApplyResult.wait, async_results)
        lst_results=[r.get() for r in async_results]
        print lst_results

    def __call__(self, i):
        self.process_obj(i)

    def __del__(self):
        print "... Destructor"

    def process_obj(self, i):
        print "obj %d" % i
        return "result"

Myclass(nobj=8, workers=3)
# problem !!! the destructor is called nobj times (instead of once), 
# **and** results are empty !

So none of both methods is satisfying...

jquery json to string?

I use

$.param(jsonObj)

which gets me the string.

Automatically pass $event with ng-click?

Add a $event to the ng-click, for example:

<button type="button" ng-click="saveOffer($event)" accesskey="S"></button>

Then the jQuery.Event was passed to the callback:

enter image description here

Eslint: How to disable "unexpected console statement" in Node.js?

You should update eslint config file to fix this permanently. Else you can temporarily enable or disable eslint check for console like below

/* eslint-disable no-console */
console.log(someThing);
/* eslint-enable no-console */

No Access-Control-Allow-Origin header is present on the requested resource

I find the solution in spring.io,like this:

    response.setHeader("Access-Control-Allow-Origin", "*");
    response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
    response.setHeader("Access-Control-Max-Age", "3600");
    response.setHeader("Access-Control-Allow-Headers", "x-requested-with");

How to replace part of string by position?

        string s = "ABCDEFG";
        string t = "st";
        s = s.Remove(4, t.Length);
        s = s.Insert(4, t);

How to set headers in http get request?

The Header field of the Request is public. You may do this :

req.Header.Set("name", "value")

AngularJS: Uncaught Error: [$injector:modulerr] Failed to instantiate module?

For people having the same error with a similar code:

$(function(){
    var app = angular.module("myApp", []); 
    app.controller('myController', function(){

    });
});

Removing the $(function(){ ... }); solved the error.

php: Get html source code with cURL

I found a tool in Github that could possibly be a solution to this question. https://incarnate.github.io/curl-to-php/ I hope that will be useful

Is there a concurrent List in Java's JDK?

`ConcurrentLinkedQueue`

If you don't care about having index-based access and just want the insertion-order-preserving characteristics of a List, you could consider a java.util.concurrent.ConcurrentLinkedQueue. Since it implements Iterable, once you've finished adding all the items, you can loop over the contents using the enhanced for syntax:

Queue<String> globalQueue = new ConcurrentLinkedQueue<String>();

//Multiple threads can safely call globalQueue.add()...

for (String href : globalQueue) {
    //do something with href
}

How do I create an executable in Visual Studio 2013 w/ C++?

Click BUILD > Configuration Manager...
Under Project contexts > Configuration, select "Release"
BUILD > Build Solution or Rebuild Solution

How can I trigger a JavaScript event click

IE9+

function triggerEvent(el, type){
    var e = document.createEvent('HTMLEvents');
    e.initEvent(type, false, true);
    el.dispatchEvent(e);
}

Usage example:

var el = document.querySelector('input[type="text"]');
triggerEvent(el, 'mousedown');

Source: https://plainjs.com/javascript/events/trigger-an-event-11/

How to justify navbar-nav in Bootstrap 3

You can justify the navbar contents by using:

@media (min-width: 768px){
  .navbar-nav{
     margin: 0 auto;
     display: table;
     table-layout: fixed;
     float: none;
  }
}

See this live: http://jsfiddle.net/panchroma/2fntE/

Good luck!

Making href (anchor tag) request POST instead of GET?

To do POST you'll need to have a form.

<form action="employee.action" method="post">
    <input type="submit" value="Employee1" />
</form>

There are some ways to post data with hyperlinks, but you'll need some javascript, and a form.

Some tricks: Make a link use POST instead of GET and How do you post data with a link

Edit: to load response on a frame you can target your form to your frame:

<form action="employee.action" method="post" target="myFrame">

convert array into DataFrame in Python

You can add parameter columns or use dict with key which is converted to column name:

np.random.seed(123)
e = np.random.normal(size=10)  
dataframe=pd.DataFrame(e, columns=['a']) 
print (dataframe)
          a
0 -1.085631
1  0.997345
2  0.282978
3 -1.506295
4 -0.578600
5  1.651437
6 -2.426679
7 -0.428913
8  1.265936
9 -0.866740

e_dataframe=pd.DataFrame({'a':e}) 
print (e_dataframe)
          a
0 -1.085631
1  0.997345
2  0.282978
3 -1.506295
4 -0.578600
5  1.651437
6 -2.426679
7 -0.428913
8  1.265936
9 -0.866740

Capture screenshot of active window?

Use the following code :

            // Shot size = screen size
            Size shotSize = Screen.PrimaryScreen.Bounds.Size;

            // the upper left point in the screen to start shot
            // 0,0 to get the shot from upper left point
            Point upperScreenPoint = new Point(0, 0);

            // the upper left point in the image to put the shot
            Point upperDestinationPoint = new Point(0, 0);

            // create image to get the shot in it
            Bitmap shot = new Bitmap(shotSize.Width, shotSize.Height);

            // new Graphics instance 
            Graphics graphics = Graphics.FromImage(shot);

            // get the shot by Graphics class 
            graphics.CopyFromScreen(upperScreenPoint, upperDestinationPoint, shotSize);

            // return the image
            pictureBox1.Image = shot;

Uncaught (in promise): Error: StaticInjectorError(AppModule)[options]

Here is what worked for me (Angular 7):

First import HttpClientModule in your app.module.ts if you didn't:

import { HttpClientModule } from '@angular/common/http';
...
imports: [
        HttpClientModule
    ],

Then change your service

@Injectable()
export class FooService {

@Injectable({
    providedIn: 'root'
})
export class FooService {

Hope it helps.

Edit:

providedIn

Determines which injectors will provide the injectable, by either associating it with an @NgModule or other InjectorType, or by specifying that this injectable should be provided in one of the following injectors:

'root' : The application-level injector in most apps.

'platform' : A special singleton platform injector shared by all applications on the page.

'any' : Provides a unique instance in every module (including lazy modules) that injects the token.

Be careful platform is available only since Angular 9 (https://blog.angular.io/version-9-of-angular-now-available-project-ivy-has-arrived-23c97b63cfa3)

Read more about Injectable here: https://angular.io/api/core/Injectable

Programs & Examples On #Fixed

HTML table with horizontal scrolling (first column fixed)

parent & child with position fixed, parent overflow:hidden bug

Fixed position but relative to container

Fixed header table with horizontal scrollbar and vertical scrollbar on

Fixed positioned div within a relative parent div

How to make a div have a fixed size?

Stop fixed position at footer

How can I fix the form size in a C# Windows Forms application and not to let user change its size?

How to fix a header on scroll

Passing an array as an argument to a function in C

1. Standard array usage in C with natural type decay from array to ptr

2. Forcing type safety on arrays in C

References

Shortcut for changing font size

Spring RestTemplate timeout

How to read a list of files from a folder using PHP?

Regex to check whether a string contains only numbers

How to change value for innodb_buffer_pool_size in MySQL on Mac OS?

UPDATE :

python-dev installation error: ImportError: No module named apt_pkg

What is process.env.PORT in Node.js?

SQL Server Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >=

Find out whether radio button is checked with JQuery?

How to create a RelativeLayout programmatically with two buttons one on top of the other?

Purpose of installing Twitter Bootstrap through npm?

Can I connect to SQL Server using Windows Authentication from Java EE webapp?

How to get share counts using graph API

How do I set combobox read-only or user cannot write in a combo box only can select the given items?

PersistenceContext EntityManager injection NullPointerException

Android Studio: /dev/kvm device permission denied

Horizontal swipe slider with jQuery and touch devices support?

535-5.7.8 Username and Password not accepted

Is there a float input type in HTML5?

How to convert WebResponse.GetResponseStream return into a string?

When to use dynamic vs. static libraries

"unrecognized import path" with go get

AWS S3 copy files and folders between two buckets

How to implement oauth2 server in ASP.NET MVC 5 and WEB API 2

Android Material Design Button Styles

How to check queue length in Python

CSS Div width percentage and padding without breaking layout

jQuery get input value after keypress

PHP How to find the time elapsed since a date time?

Async always WaitingForActivation

How to test if a string is basically an integer in quotes using Ruby

Entity Framework - Generating Classes

shorthand If Statements: C#

Capitalize only first character of string and leave others alone? (Rails)

How can I convert a file pointer ( FILE* fp ) to a file descriptor (int fd)?

.NET NewtonSoft JSON deserialize map to a different property name

What is JSONP, and why was it created?

How to break long string to multiple lines

What .NET collection provides the fastest search

Mongoose limit/offset and count query

Which is preferred: Nullable<T>.HasValue or Nullable<T> != null?

How to hide a mobile browser's address bar?

log4j:WARN No appenders could be found for logger in web.xml

When should I use semicolons in SQL Server?

Wget output document and headers to STDOUT

Send string to stdin

Display last git commit comment

How can I find out which server hosts LDAP on my windows domain?

Gradle - Error Could not find method implementation() for arguments [com.android.support:appcompat-v7:26.0.0]

Error: Java: invalid target release: 11 - IntelliJ IDEA

git cherry-pick says "...38c74d is a merge but no -m option was given"

How to get just the date part of getdate()?

Composer update memory limit

Why does this CSS margin-top style not work?

Sum all the elements java arraylist

'nuget' is not recognized but other nuget commands working

System.currentTimeMillis() vs. new Date() vs. Calendar.getInstance().getTime()

How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?

drop down list value in asp.net

Chrome desktop notification example

How to compare datetime with only date in SQL Server

How to copy java.util.list Collection

How to get a view table query (code) in SQL Server 2008 Management Studio

Get current folder path

How do I create a singleton service in Angular 2?

ModuleNotFoundError: What does it mean main is not a package?

GUI equivalent for `hg commit --amend`: