Programs & Examples On #Webkit

WebKit is an open-source Web content engine for browsers and other applications, such as Apple Safari, Mail, App Store and several mobile browsers including the pre-installed browsers for Android, iOS, RIM Blackberry, Symbian, and WebOS.

Submitting a form on 'Enter' with jQuery?

In addition to return false as Jason Cohen mentioned. You may have to also preventDefault

e.preventDefault();

How can I debug javascript on Android?

Raphael is not supported on pre 3.0 Android browsers, that's what your problem is. They have no support for SVG graphics. It does have support for canvas though. If you don't need to animate it, you could render the graphics with canvg:

http://code.google.com/p/canvg/

That's how we got around this issue for rendering SVG icons in the default Android browser.

CSS transition shorthand with multiple properties?

I think that this should work:

.element {
   -webkit-transition: all .3s;
   -moz-transition: all .3s;
   -o-transition: all .3s;
   transition: all .3s;
}

Interpreting segfault messages

Error 4 means "The cause was a user-mode read resulting in no page being found.". There's a tool that decodes it here.

Here's the definition from the kernel. Keep in mind that 4 means that bit 2 is set and no other bits are set. If you convert it to binary that becomes clear.

/*
 * Page fault error code bits
 *      bit 0 == 0 means no page found, 1 means protection fault
 *      bit 1 == 0 means read, 1 means write
 *      bit 2 == 0 means kernel, 1 means user-mode
 *      bit 3 == 1 means use of reserved bit detected
 *      bit 4 == 1 means fault was an instruction fetch
 */
#define PF_PROT         (1<<0)
#define PF_WRITE        (1<<1)
#define PF_USER         (1<<2)
#define PF_RSVD         (1<<3)
#define PF_INSTR        (1<<4)

Now then, "ip 00007f9bebcca90d" means the instruction pointer was at 0x00007f9bebcca90d when the segfault happened.

"libQtWebKit.so.4.5.2[7f9beb83a000+f6f000]" tells you:

  • The object the crash was in: "libQtWebKit.so.4.5.2"
  • The base address of that object "7f9beb83a000"
  • How big that object is: "f6f000"

If you take the base address and subtract it from the ip, you get the offset into that object:

0x00007f9bebcca90d - 0x7f9beb83a000 = 0x49090D

Then you can run addr2line on it:

addr2line -e /usr/lib64/qt45/lib/libQtWebKit.so.4.5.2 -fCi 0x49090D
??
??:0

In my case it wasn't successful, either the copy I installed isn't identical to yours, or it's stripped.

Background color not showing in print preview

I just needed to add the !important attribute onto the the background-color tag in order for it to show up, did not need the webkit part:

background-color: #f5f5f5 !important;

Convert Data URI to File then append to FormData

BlobBuilder and ArrayBuffer are now deprecated, here is the top comment's code updated with Blob constructor:

function dataURItoBlob(dataURI) {
    var binary = atob(dataURI.split(',')[1]);
    var array = [];
    for(var i = 0; i < binary.length; i++) {
        array.push(binary.charCodeAt(i));
    }
    return new Blob([new Uint8Array(array)], {type: 'image/jpeg'});
}

CSS endless rotation animation

Without any prefixes, e.g. at it's simplest:

.loading-spinner {
  animation: rotate 1.5s linear infinite;
}

@keyframes rotate {
  to {
    transform: rotate(360deg);
  }
}

CSS full screen div with text in the middle

There is no pure CSS solution to this classical problem.

If you want to achieve this, you have two solutions:

  • Using a table (ugly, non semantic, but the only way to vertically align things that are not a single line of text)
  • Listening to window.resize and absolute positionning

EDIT: when I say that there is no solution, I take as an hypothesis that you don't know in advance the size of the block to center. If you know it, paislee's solution is very good

How to set the style -webkit-transform dynamically using JavaScript?

Try using

img.style.webkitTransform = "rotate(60deg)"

Add custom headers to WebView resource requests - android

This worked for me. Create WebViewClient like this below and set the webclient to your webview. I had to use webview.loadDataWithBaseURL as my urls (in my content) did not have the baseurl but only relative urls. You will get the url correctly only when there is a baseurl set using loadDataWithBaseURL.

public WebViewClient getWebViewClientWithCustomHeader(){
    return new WebViewClient() {
        @Override
        public WebResourceResponse shouldInterceptRequest(WebView view, String url) {
            try {
                OkHttpClient httpClient = new OkHttpClient();
                com.squareup.okhttp.Request request = new com.squareup.okhttp.Request.Builder()
                        .url(url.trim())
                        .addHeader("<your-custom-header-name>", "<your-custom-header-value>")
                        .build();
                com.squareup.okhttp.Response response = httpClient.newCall(request).execute();

                return new WebResourceResponse(
                        response.header("content-type", response.body().contentType().type()), // You can set something other as default content-type
                        response.header("content-encoding", "utf-8"),  // Again, you can set another encoding as default
                        response.body().byteStream()
                );
            } catch (ClientProtocolException e) {
                //return null to tell WebView we failed to fetch it WebView should try again.
                return null;
            } catch (IOException e) {
                //return null to tell WebView we failed to fetch it WebView should try again.
                return null;
            }
        }
    };

}

Rotate and translate

I can't comment so here goes. About @David Storey answer.

Be careful on the "order of execution" in CSS3 chains! The order is right to left, not left to right.

transformation: translate(0,10%) rotate(25deg);

The rotate operation is done first, then the translate.

See: CSS3 transform order matters: rightmost operation first

text-align: right on <select> or <option>

I think what you want is:

select {
  direction: rtl;
}

fiddled here: http://jsfiddle.net/neilheinrich/XS3yQ/

How do I print an IFrame from javascript in Safari/Chrome

Here is my complete, cross browser solution:

In the iframe page:

function printPage() { print(); }

In the main page

function printIframe(id)
{
    var iframe = document.frames
        ? document.frames[id]
        : document.getElementById(id);
    var ifWin = iframe.contentWindow || iframe;

    iframe.focus();
    ifWin.printPage();
    return false;
}

Update: Many people seem to be having problems with this in versions of IE released since I had this problem. I do not have the time to re-investigate this right now, but, if you are stuck I suggest you read all the comments in this entire thread!

Twitter Bootstrap modal on mobile devices

EDIT: An unofficial Bootstrap Modal modification has been built to address responsive/mobile issues. This is perhaps the simplest and easiest way to remedy the problem.

There has since been a fix found in one of the issues you discussed earlier

in bootstrap-responsive.css

.modal { 
    position: fixed; 
    top: 3%; 
    right: 3%; 
    left: 3%; 
    width: auto; 
    margin: 0; 
}
.modal-body { 
    height: 60%; 
}

and in bootstrap.css

.modal-body { 
    max-height: 350px; 
    padding: 15px; 
    overflow-y: auto; 
    -webkit-overflow-scrolling: touch; 
 }

Custom bullet symbol for <li> elements in <ul> that is a regular character, and not an image

_x000D_
_x000D_
.single-before {_x000D_
  list-style: "";_x000D_
  list-style-position: outside!important;_x000D_
}
_x000D_
<ul class="single-before">_x000D_
  <li> is to manifest perfection already in man.</li>_x000D_
  <li> is to bring out the best facets of our students personalities.</li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

Javascript / Chrome - How to copy an object from the webkit inspector as code

You can now accomplish this in Chrome by right clicking on the object and selecting "Store as Global Variable": http://www.youtube.com/watch?v=qALFiTlVWdg

enter image description here

Blurry text after using CSS transform: scale(); in Chrome

For me the problem was that my elements were using transformStyle: preserve-3d. I realized that this wasn't actually needed for the app and removing it fixed the blurriness.

What are -moz- and -webkit-?

What are -moz- and -webkit-?

CSS properties starting with -webkit-, -moz-, -ms- or -o- are called vendor prefixes.


Why do different browsers add different prefixes for the same effect?

A good explanation of vendor prefixes comes from Peter-Paul Koch of QuirksMode:

Originally, the point of vendor prefixes was to allow browser makers to start supporting experimental CSS declarations.

Let's say a W3C working group is discussing a grid declaration (which, incidentally, wouldn't be such a bad idea). Let's furthermore say that some people create a draft specification, but others disagree with some of the details. As we know, this process may take ages.

Let's furthermore say that Microsoft as an experiment decides to implement the proposed grid. At this point in time, Microsoft cannot be certain that the specification will not change. Therefore, instead of adding the grid to its CSS, it adds -ms-grid.

The vendor prefix kind of says "this is the Microsoft interpretation of an ongoing proposal." Thus, if the final definition of the grid is different, Microsoft can add a new CSS property grid without breaking pages that depend on -ms-grid.


UPDATE AS OF THE YEAR 2016

As this post 3 years old, it's important to mention that now most vendors do understand that these prefixes are just creating un-necessary duplicate code and that the situation where you need to specify 3 different CSS rules to get one effect working in all browser is an unwanted one.

As mentioned in this glossary about Mozilla's view on Vendor Prefix on May 3, 2016,

Browser vendors are now trying to get rid of vendor prefix for experimental features. They noticed that Web developers were using them on production Web sites, polluting the global space and making it more difficult for underdogs to perform well.

For example, just a few years ago, to set a rounded corner on a box you had to write:

-moz-border-radius: 10px 5px;
-webkit-border-top-left-radius: 10px;
-webkit-border-top-right-radius: 5px;
-webkit-border-bottom-right-radius: 10px;
-webkit-border-bottom-left-radius: 5px;
border-radius: 10px 5px;

But now that browsers have come to fully support this feature, you really only need the standardized version:

border-radius: 10px 5px;

Finding the right rules for all browsers

As still there's no standard for common CSS rules that work on all browsers, you can use tools like caniuse.com to check support of a rule across all major browsers.

You can also use pleeease.io/play. Pleeease is a Node.js application that easily processes your CSS. It simplifies the use of preprocessors and combines them with best postprocessors. It helps create clean stylesheets, support older browsers and offers better maintainability.

Input:

a {
  column-count: 3;
  column-gap: 10px;
  column-fill: auto;
}

Output:

a {
  -webkit-column-count: 3;
     -moz-column-count: 3;
          column-count: 3;
  -webkit-column-gap: 10px;
     -moz-column-gap: 10px;
          column-gap: 10px;
  -webkit-column-fill: auto;
     -moz-column-fill: auto;
          column-fill: auto;
}

Chrome/jQuery Uncaught RangeError: Maximum call stack size exceeded

You can also get this error when you have an infinite loop. Make sure that you don't have any unending, recursive self references.

What is WebKit and how is it related to CSS?

Webkit is an HTML rendering engine used by Chrome and Safari.

It supports a number of custom CSS properties that are prefixed by -webkit-.

jQuery get the location of an element relative to window

TL;DR

headroom_by_jQuery = $('#id').offset().top - $(window).scrollTop();

headroom_by_DOM = $('#id')[0].getBoundingClientRect().top;   // if no iframe

.getBoundingClientRect() appears to be universal. .offset() and .scrollTop() have been supported since jQuery 1.2. Thanks @user372551 and @prograhammer. To use DOM in an iframe see @ImranAnsari's solution.

Removing rounded corners from a <select> element in Chrome/Webkit

If you want square borders and still want the little expander arrow, I recommend this:

select.squarecorners{
     border: 0;
     outline: 1px solid #CCC;
     background-color: white;
}

HTML5 placeholder css padding

I noticed the issue the moment I updated Chrome on os x to the latest stable release (9.0.597.94) so this is a Chrome bug and hopefully will be fixed.

I'm tempted not to even attempt to work around this and just wait for the fix. It'll just mean more work taking it out.

Maximum call stack size exceeded error

For me as a beginner in TypeScript, it was a problem in the getter and the setter of _var1.

class Point2{
    
    constructor(private _var1?: number, private y?: number){}

    set var1(num: number){
        this._var1 = num  // problem was here, it was this.var1 = num
    }
    get var1(){
        return this._var1 // this was return this.var1
    }
}

com.apple.WebKit.WebContent drops 113 error: Could not find specified service

In my case I was launching a WKWebView and displaying a website. Then (within 25 seconds) I deallocated the WKWebView. But 25-60 seconds after launching the WKWebView I received this "113" error message. I assume the system was trying to signal something to the WKWebView and couldn't find it because it was deallocated.

The fix was simply to leave the WKWebView allocated.

What is the correct "-moz-appearance" value to hide dropdown arrow of a <select> element

While you can't yet get Firefox to remove the dropdown arrow (see MatTheCat's post), you can hide your "stylized" background image from showing in Firefox.

-moz-background-position: -9999px -9999px!important;

This will position it out of frame, leaving you with the default select box arrow – while keeping the stylized version in Webkit.

How can I force WebKit to redraw/repaint to propagate style changes?

I came up here because I needed to redraw scrollbars in Chrome after changing its css.

If someone's having the same problem, I solved it by calling this function:

//Hack to force scroll redraw
function scrollReDraw() {
    $('body').css('overflow', 'hidden').height();
    $('body').css('overflow', 'auto');
}

This method is not the best solution, but it may work with everything, hiding and showing the element that needs to be redraw may solve every problem.

Here is the fiddle where I used it: http://jsfiddle.net/promatik/wZwJz/18/

css3 transition animation on load?

If anyone else had problems doing two transitions at once, here's what I did. I needed text to come from top to bottom on page load.

HTML

<body class="existing-class-name" onload="document.body.classList.add('loaded')">

HTML

<div class="image-wrapper">
    <img src="db-image.jpg" alt="db-image-name">
    <span class="text-over-image">DB text</span>
</div>

CSS

.text-over-image {
    position: absolute;
    background-color: rgba(110, 186, 115, 0.8);
    color: #eee;
    left: 0;
    width: 100%;
    padding: 10px;
    opacity: 0;
    bottom: 100%;
    -webkit-transition: opacity 2s, bottom 2s;
    -moz-transition: opacity 2s, bottom 2s;
    -o-transition: opacity 2s, bottom 2s;
    transition: opacity 2s, bottom 2s;
}

body.loaded .text-over-image {
    bottom: 0;
    opacity: 1;
}

Don't know why I kept trying to use 2 transition declarations in 1 selector and (not really) thinking it would use both.

Disable webkit's spin buttons on input type="number"?

Not sure if this is the best way to do it, but this makes the spinners disappear on Chrome 8.0.552.5 dev:

input[type=number]::-webkit-inner-spin-button {
    -webkit-appearance: none;
}

Firing a Keyboard Event in Safari, using JavaScript

Did you dispatch the event correctly?

function simulateKeyEvent(character) {
  var evt = document.createEvent("KeyboardEvent");
  (evt.initKeyEvent || evt.initKeyboardEvent)("keypress", true, true, window,
                    0, 0, 0, 0,
                    0, character.charCodeAt(0)) 
  var canceled = !body.dispatchEvent(evt);
  if(canceled) {
    // A handler called preventDefault
    alert("canceled");
  } else {
    // None of the handlers called preventDefault
    alert("not canceled");
  }
}

If you use jQuery, you could do:

function simulateKeyPress(character) {
  jQuery.event.trigger({ type : 'keypress', which : character.charCodeAt(0) });
}

CSS3 Continuous Rotate Animation (Just like a loading sundial)

You could use animation like this:

-webkit-animation: spin 1s infinite linear;

@-webkit-keyframes spin {
    0%   {-webkit-transform: rotate(0deg)}
    100% {-webkit-transform: rotate(360deg)}
}

Video auto play is not working in Safari and Chrome desktop browser

Google just changed their policy for autoplay videos, it has to be muted

You can check here

so just add muted

<video height="256" loop="true" autoplay="autoplay" controls="controls" id="vid" muted>
         <source type="video/mp4" src="video_file.mp4"></source>
         <source type="video/ogg" src="video_file.ogg"></source>
</video>

Detect rotation of Android phone in the browser with JavaScript

two-bit-fool's excellent answer provides all the background, but let me attempt a concise, pragmatic summary of how to handle orientation changes across iOS and Android:

  • If you only care about window dimensions (the typical scenario) - and not about the specific orientation:
    • Handle the resize event only.
    • In your handler, act on window.innerWidth and window.InnerHeight only.
    • Do NOT use window.orientation - it won't be current on iOS.
  • If you DO care about the specific orientation:
    • Handle only the resize event on Android, and only the orientationchange event on iOS.
    • In your handler, act on window.orientation (and window.innerWidth and window.InnerHeight)

These approaches offer slight benefits over remembering the previous orientation and comparing:

  • the dimensions-only approach also works while developing on desktop browsers that can otherwise simulate mobile devices, e.g., Chrome 23. (window.orientation is not available on desktop browsers).
  • no need for a global/anonymous-file-level-function-wrapper-level variable.

How to create a pulse effect using -webkit-animation - outward rings

You have a lot of unnecessary keyframes. Don't think of keyframes as individual frames, think of them as "steps" in your animation and the computer fills in the frames between the keyframes.

Here is a solution that cleans up a lot of code and makes the animation start from the center:

.gps_ring {
    border: 3px solid #999;
    -webkit-border-radius: 30px;
    height: 18px;
    width: 18px;
    position: absolute;
    left:20px;
    top:214px;
    -webkit-animation: pulsate 1s ease-out;
    -webkit-animation-iteration-count: infinite; 
    opacity: 0.0
}
@-webkit-keyframes pulsate {
    0% {-webkit-transform: scale(0.1, 0.1); opacity: 0.0;}
    50% {opacity: 1.0;}
    100% {-webkit-transform: scale(1.2, 1.2); opacity: 0.0;}
}

You can see it in action here: http://jsfiddle.net/Fy8vD/

Get the real width and height of an image with JavaScript? (in Safari/Chrome)

As stated before, Xavi answer won't work if images are in the cache. The issue responds to webkit not firing the load event on cached images, so if the width/height attrs are no explicitly set in the img tag, the only reliable way to get the images is to wait for the window.load event to be fired.

The window.load event will fire always, so it's safe to access the width/height of and img after that without any trick.

$(window).load(function(){

   //these all work

   $('img#someId').css('width');
   $('img#someId').width();
   $('img#someId').get(0).style.width;
   $('img#someId').get(0).width; 

});

If you need to get the size of dynamically loaded images that might get cached (previously loaded), you can use Xavi method plus a query string to trigger a cache refresh. The downside is that it will cause another request to the server, for an img that is already cached and should be already available. Stupid Webkit.

var pic_real_width   = 0,
    img_src_no_cache = $('img#someId').attr('src') + '?cache=' + Date.now();

$('<img/>').attr('src', img_src_no_cache).load(function(){

   pic_real_width = this.width;

});

ps: if you have a QueryString in the img.src already, you will have to parse it and add the extra param to clear the cache.

How to remove the border highlight on an input text element

I tried all the answers and I still couldn't get mine to work on Mobile, until I found -webkit-tap-highlight-color.

So, what worked for me is...

* { -webkit-tap-highlight-color: transparent; }

Custom CSS Scrollbar for Firefox

I thought I would share my findings in case someone is considering a JQuery plugin to do the job.

I gave JQuery Custom Scrollbar a go. It's pretty fancy and does some smooth scrolling (with scrolling inertia) and has loads of parameters you can tweak, but it ended up being a bit too CPU intensive for me (and it adds a fair amount to the DOM).

Now I'm giving Perfect Scrollbar a go. It's simple and lightweight (6KB) and it's doing a decent job so far. It's not CPU intensive at all (as far as I can tell) and adds very little to your DOM. It's only got a couple of parameters to tweak (wheelSpeed and wheelPropagation), but it's all I need and it handles updates to the scrolling content nicely (such as loading images).

P.S. I did have a quick look at JScrollPane, but @simone is right, it's a bit dated now and a PITA.

How to style HTML5 range input to have different color before and after slider?

input type="range" min="0" max="50" value="0"  style="margin-left: 6%;width: 88%;background-color: whitesmoke;"

above code changes range input style.....

Preventing scroll bars from being hidden for MacOS trackpad users in WebKit/Blink

For a one-page web application where I add scrollable sections dynamically, I trigger OSX's scrollbars by programmatically scrolling one pixel down and back up:

// Plain JS:
var el = document.getElementById('scrollable-section');
el.scrollTop = 1;
el.scrollTop = 0;

// jQuery:
$('#scrollable-section').scrollTop(1).scrollTop(0);

This triggers the visual cue fading in and out.

CSS media query to target iPad and iPad only?

I am a bit late to answer this but none of the above worked for me.

This is what worked for me

@media only screen and (min-device-width: 768px) and (max-device-width: 1024px) {
    //your styles here
   }

Chrome / Safari not filling 100% height of flex parent

Solution

Use nested flex containers.

Get rid of percentage heights. Get rid of table properties. Get rid of vertical-align. Avoid absolute positioning. Just stick with flexbox all the way through.

Apply display: flex to the flex item (.item), making it a flex container. This automatically sets align-items: stretch, which tells the child (.item-inner) to expand the full height of the parent.

Important: Remove specified heights from flex items for this method to work. If a child has a height specified (e.g. height: 100%), then it will ignore the align-items: stretch coming from the parent. For the stretch default to work, the child's height must compute to auto (full explanation).

Try this (no changes to HTML):

_x000D_
_x000D_
.container {_x000D_
    display: flex;_x000D_
    flex-direction: column;_x000D_
    height: 20em;_x000D_
    border: 5px solid black_x000D_
}_x000D_
_x000D_
.item {_x000D_
    display: flex;                      /* new; nested flex container */_x000D_
    flex: 1;_x000D_
    border-bottom: 1px solid white;_x000D_
}_x000D_
_x000D_
.item-inner {_x000D_
    display: flex;                      /* new; nested flex container */_x000D_
    flex: 1;                            /* new */_x000D_
_x000D_
    /* height: 100%;                    <-- remove; unnecessary */_x000D_
    /* width: 100%;                     <-- remove; unnecessary */_x000D_
    /* display: table;                  <-- remove; unnecessary */  _x000D_
}_x000D_
_x000D_
a {_x000D_
    display: flex;                      /* new; nested flex container */_x000D_
    flex: 1;                            /* new */_x000D_
    align-items: center;                /* new; vertically center text */_x000D_
    background: orange;_x000D_
_x000D_
    /* display: table-cell;             <-- remove; unnecessary */_x000D_
    /* vertical-align: middle;          <-- remove; unnecessary */_x000D_
}
_x000D_
<div class="container">_x000D_
  <div class="item">_x000D_
    <div class="item-inner">_x000D_
      <a>Button</a>_x000D_
    </div>_x000D_
  </div>_x000D_
_x000D_
  <div class="item">_x000D_
    <div class="item-inner">_x000D_
      <a>Button</a>_x000D_
    </div>_x000D_
  </div>_x000D_
_x000D_
  <div class="item">_x000D_
    <div class="item-inner">_x000D_
      <a>Button</a>_x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

jsFiddle demo


Explanation

My problem is that .item-inner { height: 100% } is not working in webkit (Chrome).

It's not working because you're using percentage height in a way that doesn't conform with the traditional implementation of the spec.

10.5 Content height: the height property

percentage
Specifies a percentage height. The percentage is calculated with respect to the height of the generated box's containing block. If the height of the containing block is not specified explicitly and this element is not absolutely positioned, the value computes to auto.

auto
The height depends on the values of other properties.

In other words, for percentage height to work on an in-flow child, the parent must have a set height.

In your code, the top-level container has a defined height: .container { height: 20em; }

The third-level container has a defined height: .item-inner { height: 100%; }

But between them, the second-level container – .itemdoes not have a defined height. Webkit sees that as a missing link.

.item-inner is telling Chrome: give me height: 100%. Chrome looks to the parent (.item) for reference and responds: 100% of what? I don't see anything (ignoring the flex: 1 rule that is there). As a result, it applies height: auto (content height), in accordance with the spec.

Firefox, on the other hand, now accepts a parent's flex height as a reference for the child's percentage height. IE11 and Edge accept flex heights, as well.

Also, Chrome will accept flex-grow as an adequate parent reference if used in conjunction with flex-basis (any numerical value works (auto won't), including flex-basis: 0). As of this writing, however, this solution fails in Safari.

_x000D_
_x000D_
#outer {_x000D_
  display: flex;_x000D_
  flex-direction: column;_x000D_
  height: 300px;_x000D_
  background-color: white;_x000D_
  border: 1px solid red;_x000D_
}_x000D_
#middle {_x000D_
  flex-grow: 1;_x000D_
  flex-basis: 1px;_x000D_
  background-color: yellow;_x000D_
}_x000D_
#inner {_x000D_
  height: 100%;_x000D_
  background-color: lightgreen;_x000D_
}
_x000D_
<div id="outer">_x000D_
  <div id="middle">_x000D_
    <div id="inner">_x000D_
      INNER_x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_


Four Solutions

1. Specify a height on all parent elements

A reliable cross-browser solution is to specify a height on all parent elements. This prevents missing links, which Webkit-based browsers consider a violation of the spec.

Note that min-height and max-height are not acceptable. It must be the height property.

More details here: Working with the CSS height property and percentage values

2. CSS Relative & Absolute Positioning

Apply position: relative to the parent and position: absolute to the child.

Size the child with height: 100% and width: 100%, or use the offset properties: top: 0, right: 0, bottom: 0, left: 0.

With absolute positioning, percentage height works without a specified height on the parent.

3. Remove unnecessary HTML containers (recommended)

Is there a need for two containers around button? Why not remove .item or .item-inner, or both? Although button elements sometimes fail as flex containers, they can be flex items. Consider making button a child of .container or .item, and removing gratuitous mark-up.

Here's an example:

_x000D_
_x000D_
.container {_x000D_
    height: 20em;_x000D_
    display: flex;_x000D_
    flex-direction: column;_x000D_
    border: 5px solid black_x000D_
}_x000D_
_x000D_
a {_x000D_
    flex: 1;_x000D_
    background: orange;_x000D_
    border-bottom: 1px solid white;_x000D_
    display: flex;                   /* nested flex container (for aligning text) */_x000D_
    align-items: center;             /* center text vertically */_x000D_
    justify-content: center;         /* center text horizontally */_x000D_
}
_x000D_
<div class="container">_x000D_
    <a>Button</a>_x000D_
    <a>Button</a>_x000D_
    <a>Button</a>_x000D_
</div>
_x000D_
_x000D_
_x000D_

4. Nested Flex Containers (recommended)

Get rid of percentage heights. Get rid of table properties. Get rid of vertical-align. Avoid absolute positioning. Just stick with flexbox all the way through.

Apply display: flex to the flex item (.item), making it a flex container. This automatically sets align-items: stretch, which tells the child (.item-inner) to expand the full height of the parent.

Important: Remove specified heights from flex items for this method to work. If a child has a height specified (e.g. height: 100%), then it will ignore the align-items: stretch coming from the parent. For the stretch default to work, the child's height must compute to auto (full explanation).

Try this (no changes to HTML):

_x000D_
_x000D_
.container {_x000D_
    display: flex;_x000D_
    flex-direction: column;_x000D_
    height: 20em;_x000D_
    border: 5px solid black_x000D_
}_x000D_
_x000D_
.item {_x000D_
    display: flex;                      /* new; nested flex container */_x000D_
    flex: 1;_x000D_
    border-bottom: 1px solid white;_x000D_
}_x000D_
_x000D_
.item-inner {_x000D_
    display: flex;                      /* new; nested flex container */_x000D_
    flex: 1;                            /* new */_x000D_
_x000D_
    /* height: 100%;                    <-- remove; unnecessary */_x000D_
    /* width: 100%;                     <-- remove; unnecessary */_x000D_
    /* display: table;                  <-- remove; unnecessary */  _x000D_
}_x000D_
_x000D_
a {_x000D_
    display: flex;                      /* new; nested flex container */_x000D_
    flex: 1;                            /* new */_x000D_
    align-items: center;                /* new; vertically center text */_x000D_
    background: orange;_x000D_
_x000D_
    /* display: table-cell;             <-- remove; unnecessary */_x000D_
    /* vertical-align: middle;          <-- remove; unnecessary */_x000D_
}
_x000D_
<div class="container">_x000D_
  <div class="item">_x000D_
    <div class="item-inner">_x000D_
      <a>Button</a>_x000D_
    </div>_x000D_
  </div>_x000D_
_x000D_
  <div class="item">_x000D_
    <div class="item-inner">_x000D_
      <a>Button</a>_x000D_
    </div>_x000D_
  </div>_x000D_
_x000D_
  <div class="item">_x000D_
    <div class="item-inner">_x000D_
      <a>Button</a>_x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

jsFiddle

JavaScript: Is there a way to get Chrome to break on all errors?

Edit: The original link I answered with is now invalid.The newer URL would be https://developers.google.com/web/tools/chrome-devtools/javascript/add-breakpoints#exceptions as of 2016-11-11.

I realize this question has an answer, but it's no longer accurate. Use the link above ^


(link replaced by edited above) - you can now set it to break on all exceptions or just unhandled ones. (Note that you need to be in the Sources tab to see the button.)

Chrome's also added some other really useful breakpoint capabilities now, such as breaking on DOM changes or network events.

Normally I wouldn't re-answer a question, but I had the same question myself, and I found this now-wrong answer, so I figured I'd put this information in here for people who came along later in searching. :)

HTML5 Video autoplay on iPhone

I had a similar problem and I tried multiple solution. I solved it implementing 2 considerations.

  1. Using dangerouslySetInnerHtml to embed the <video> code. For example:
<div dangerouslySetInnerHTML={{ __html: `
    <video class="video-js" playsinline autoplay loop muted>
        <source src="../video_path.mp4" type="video/mp4"/>
    </video>`}}
/>
  1. Resizing the video weight. I noticed my iPhone does not autoplay videos over 3 megabytes. So I used an online compressor tool (https://www.mp4compress.com/) to go from 4mb to less than 500kb

Also, thanks to @boltcoder for his guide: Autoplay muted HTML5 video using React on mobile (Safari / iOS 10+)

What does the shrink-to-fit viewport meta attribute do?

As stats on iOS usage, indicating that iOS 9.0-9.2.x usage is currently at 0.17%. If these numbers are truly indicative of global use of these versions, then it’s even more likely to be safe to remove shrink-to-fit from your viewport meta tag.

After 9.2.x. IOS remove this tag check on its' browser.

You can check this page https://www.scottohara.me/blog/2018/12/11/shrink-to-fit.html

Unsafe JavaScript attempt to access frame with URL

I was getting the same error message when I tried to change the domain for iframe.src.

For me, the answer was to change the iframe.src to a url on the same domain, but which was actually an html re-direct page to the desired domain. The other domain then showed up in my iframe without any errors.

Worked like a charm.:)

How to put php inside JavaScript?

you need quotes around the string in javascript

var htmlString="<?php echo $htmlString; ?>";

How do I get a substring of a string in Python?

Is there a way to substring a string in Python, to get a new string from the 3rd character to the end of the string?

Maybe like myString[2:end]?

Yes, this actually works if you assign, or bind, the name,end, to constant singleton, None:

>>> end = None
>>> myString = '1234567890'
>>> myString[2:end]
'34567890'

Slice notation has 3 important arguments:

  • start
  • stop
  • step

Their defaults when not given are None - but we can pass them explicitly:

>>> stop = step = None
>>> start = 2
>>> myString[start:stop:step]
'34567890'

If leaving the second part means 'till the end', if you leave the first part, does it start from the start?

Yes, for example:

>>> start = None
>>> stop = 2
>>> myString[start:stop:step]
'12'

Note that we include start in the slice, but we only go up to, and not including, stop.

When step is None, by default the slice uses 1 for the step. If you step with a negative integer, Python is smart enough to go from the end to the beginning.

>>> myString[::-1]
'0987654321'

I explain slice notation in great detail in my answer to Explain slice notation Question.

Aligning rotated xticklabels with their respective xticks

You can set the horizontal alignment of ticklabels, see the example below. If you imagine a rectangular box around the rotated label, which side of the rectangle do you want to be aligned with the tickpoint?

Given your description, you want: ha='right'

n=5

x = np.arange(n)
y = np.sin(np.linspace(-3,3,n))
xlabels = ['Ticklabel %i' % i for i in range(n)]

fig, axs = plt.subplots(1,3, figsize=(12,3))

ha = ['right', 'center', 'left']

for n, ax in enumerate(axs):
    ax.plot(x,y, 'o-')
    ax.set_title(ha[n])
    ax.set_xticks(x)
    ax.set_xticklabels(xlabels, rotation=40, ha=ha[n])

enter image description here

HTML <select> selected option background-color CSS style

In principle, you can style it using option[selected] as selector, but that doesn't work in many browsers. Also, that only allows you to style the selected option, not the option that has hover focus.

Tested to work in Chrome 9 and Firefox 3.6, doesn't work in Internet Explorer 8.

Where is Maven's settings.xml located on Mac OS?

After I have downloaded the binary from apache site I, have placed the extracted folder in /Library
So now the location of the settings.xml file is in:

/Library/apache_maven_3.6.3/conf

Detecting real time window size changes in Angular 4

If you want to react on certain breakpoints (e.g. do something if width is less than 768px), you can also use BreakpointObserver:

import {BreakpointObserver, Breakpoints} from '@angular/cdk/layout';

{ ... }

const isSmallScreen = breakpointObserver.isMatched('(max-width: 599px)');

or even listen to changes to that breakpoint:

breakpointObserver.observe([
  '(max-width: 768px)'
    ]).subscribe(result => {
      if (result.matches) {
        doSomething();
      } else {
        // if necessary:
        doSomethingElse();
      }
    });

Relative paths based on file location instead of current working directory

@Martin Konecny's answer provides the correct answer, but - as he mentions - it only works if the actual script is not invoked through a symlink residing in a different directory.

This answer covers that case: a solution that also works when the script is invoked through a symlink or even a chain of symlinks:


Linux / GNU readlink solution:

If your script needs to run on Linux only or you know that GNU readlink is in the $PATH, use readlink -f, which conveniently resolves a symlink to its ultimate target:

 scriptDir=$(dirname -- "$(readlink -f -- "$BASH_SOURCE")")

Note that GNU readlink has 3 related options for resolving a symlink to its ultimate target's full path: -f (--canonicalize), -e (--canonicalize-existing), and -m (--canonicalize-missing) - see man readlink.
Since the target by definition exists in this scenario, any of the 3 options can be used; I've chosen -f here, because it is the most well-known one.


Multi-(Unix-like-)platform solution (including platforms with a POSIX-only set of utilities):

If your script must run on any platform that:

  • has a readlink utility, but lacks the -f option (in the GNU sense of resolving a symlink to its ultimate target) - e.g., macOS.

    • macOS uses an older version of the BSD implementation of readlink; note that recent versions of FreeBSD/PC-BSD do support -f.
  • does not even have readlink, but has POSIX-compatible utilities - e.g., HP-UX (thanks, @Charles Duffy).

The following solution, inspired by https://stackoverflow.com/a/1116890/45375, defines helper shell function, rreadlink(), which resolves a given symlink to its ultimate target in a loop - this function is in effect a POSIX-compliant implementation of GNU readlink's -e option, which is similar to the -f option, except that the ultimate target must exist.

Note: The function is a bash function, and is POSIX-compliant only in the sense that only POSIX utilities with POSIX-compliant options are used. For a version of this function that is itself written in POSIX-compliant shell code (for /bin/sh), see here.

  • If readlink is available, it is used (without options) - true on most modern platforms.

  • Otherwise, the output from ls -l is parsed, which is the only POSIX-compliant way to determine a symlink's target.
    Caveat: this will break if a filename or path contains the literal substring -> - which is unlikely, however.
    (Note that platforms that lack readlink may still provide other, non-POSIX methods for resolving a symlink; e.g., @Charles Duffy mentions HP-UX's find utility supporting the %l format char. with its -printf primary; in the interest of brevity the function does NOT try to detect such cases.)

  • An installable utility (script) form of the function below (with additional functionality) can be found as rreadlink in the npm registry; on Linux and macOS, install it with [sudo] npm install -g rreadlink; on other platforms (assuming they have bash), follow the manual installation instructions.

If the argument is a symlink, the ultimate target's canonical path is returned; otherwise, the argument's own canonical path is returned.

#!/usr/bin/env bash

# Helper function.
rreadlink() ( # execute function in a *subshell* to localize the effect of `cd`, ...

  local target=$1 fname targetDir readlinkexe=$(command -v readlink) CDPATH= 

  # Since we'll be using `command` below for a predictable execution
  # environment, we make sure that it has its original meaning.
  { \unalias command; \unset -f command; } &>/dev/null

  while :; do # Resolve potential symlinks until the ultimate target is found.
      [[ -L $target || -e $target ]] || { command printf '%s\n' "$FUNCNAME: ERROR: '$target' does not exist." >&2; return 1; }
      command cd "$(command dirname -- "$target")" # Change to target dir; necessary for correct resolution of target path.
      fname=$(command basename -- "$target") # Extract filename.
      [[ $fname == '/' ]] && fname='' # !! curiously, `basename /` returns '/'
      if [[ -L $fname ]]; then
        # Extract [next] target path, which is defined
        # relative to the symlink's own directory.
        if [[ -n $readlinkexe ]]; then # Use `readlink`.
          target=$("$readlinkexe" -- "$fname")
        else # `readlink` utility not available.
          # Parse `ls -l` output, which, unfortunately, is the only POSIX-compliant 
          # way to determine a symlink's target. Hypothetically, this can break with
          # filenames containig literal ' -> ' and embedded newlines.
          target=$(command ls -l -- "$fname")
          target=${target#* -> }
        fi
        continue # Resolve [next] symlink target.
      fi
      break # Ultimate target reached.
  done
  targetDir=$(command pwd -P) # Get canonical dir. path
  # Output the ultimate target's canonical path.
  # Note that we manually resolve paths ending in /. and /.. to make sure we
  # have a normalized path.
  if [[ $fname == '.' ]]; then
    command printf '%s\n' "${targetDir%/}"
  elif  [[ $fname == '..' ]]; then
    # Caveat: something like /var/.. will resolve to /private (assuming
    # /var@ -> /private/var), i.e. the '..' is applied AFTER canonicalization.
    command printf '%s\n' "$(command dirname -- "${targetDir}")"
  else
    command printf '%s\n' "${targetDir%/}/$fname"
  fi
)

# Determine ultimate script dir. using the helper function.
# Note that the helper function returns a canonical path.
scriptDir=$(dirname -- "$(rreadlink "$BASH_SOURCE")")

How to push both key and value into an Array in Jquery

There are no keys in JavaScript arrays. Use objects for that purpose.

var obj = {};

$.getJSON("displayjson.php",function (data) {
    $.each(data.news, function (i, news) {
        obj[news.title] = news.link;
    });                      
});

// later:
$.each(obj, function (index, value) {
    alert( index + ' : ' + value );
});

In JavaScript, objects fulfill the role of associative arrays. Be aware that objects do not have a defined "sort order" when iterating them (see below).

However, In your case it is not really clear to me why you transfer data from the original object (data.news) at all. Why do you not simply pass a reference to that object around?


You can combine objects and arrays to achieve predictable iteration and key/value behavior:

var arr = [];

$.getJSON("displayjson.php",function (data) {
    $.each(data.news, function (i, news) {
        arr.push({
            title: news.title, 
            link:  news.link
        });
    });                      
});

// later:
$.each(arr, function (index, value) {
    alert( value.title + ' : ' + value.link );
});

Correct Way to Load Assembly, Find Class and Call Run() Method

If you do not have access to the TestRunner type information in the calling assembly (it sounds like you may not), you can call the method like this:

Assembly assembly = Assembly.LoadFile(@"C:\dyn.dll");
Type     type     = assembly.GetType("TestRunner");
var      obj      = Activator.CreateInstance(type);

// Alternately you could get the MethodInfo for the TestRunner.Run method
type.InvokeMember("Run", 
                  BindingFlags.Default | BindingFlags.InvokeMethod, 
                  null,
                  obj,
                  null);

If you have access to the IRunnable interface type, you can cast your instance to that (rather than the TestRunner type, which is implemented in the dynamically created or loaded assembly, right?):

  Assembly assembly  = Assembly.LoadFile(@"C:\dyn.dll");
  Type     type      = assembly.GetType("TestRunner");
  IRunnable runnable = Activator.CreateInstance(type) as IRunnable;
  if (runnable == null) throw new Exception("broke");
  runnable.Run();

Loop Through All Subfolders Using VBA

Just a simple folder drill down.

sub sample()
    Dim FileSystem As Object
    Dim HostFolder As String

    HostFolder = "C:\"

    Set FileSystem = CreateObject("Scripting.FileSystemObject")
    DoFolder FileSystem.GetFolder(HostFolder)
end  sub

Sub DoFolder(Folder)
    Dim SubFolder
    For Each SubFolder In Folder.SubFolders
        DoFolder SubFolder
    Next
    Dim File
    For Each File In Folder.Files
        ' Operate on each file
    Next
End Sub

How to create relationships in MySQL

as ehogue said, put this in your CREATE TABLE

FOREIGN KEY (customer_id) REFERENCES customers(customer_id) 

alternatively, if you already have the table created, use an ALTER TABLE command:

ALTER TABLE `accounts`
  ADD CONSTRAINT `FK_myKey` FOREIGN KEY (`customer_id`) REFERENCES `customers` (`customer_id`) ON DELETE CASCADE ON UPDATE CASCADE;

One good way to start learning these commands is using the MySQL GUI Tools, which give you a more "visual" interface for working with your database. The real benefit to that (over Access's method), is that after designing your table via the GUI, it shows you the SQL it's going to run, and hence you can learn from that.

How to read line by line of a text area HTML tag

Try this.

var lines = $('textarea').val().split('\n');
for(var i = 0;i < lines.length;i++){
    //code here using lines[i] which will give you each line
}

How to properly create composite primary keys - MYSQL

I would use a composite (multi-column) key.

CREATE TABLE INFO (
    t1ID INT,
    t2ID INT,
    PRIMARY KEY (t1ID, t2ID)
) 

This way you can have t1ID and t2ID as foreign keys pointing to their respective tables as well.

Best way to list files in Java, sorted by Date Modified?

There is also a completely different way which may be even easier, as we do not deal with large numbers.

Instead of sorting the whole array after you retrieved all filenames and lastModified dates, you can just insert every single filename just after you retrieved it at the right position of the list.

You can do it like this:

list.add(1, object1)
list.add(2, object3)
list.add(2, object2)

After you add object2 to position 2, it will move object3 to position 3.

Horizontal scroll css?

Just set your width to auto:

#myWorkContent{
    width: auto;
    height:210px;
    border: 13px solid #bed5cd;
    overflow-x: scroll;
    overflow-y: hidden;
    white-space: nowrap;
}

This way your div can be as wide as possible, so you can add as many kitty images as possible ;3

Your div's width will expand based on the child elements it contains.

jsFiddle

Get DOM content of cross-domain iframe

There's a workaround to achieve it.

  1. First, bind your iframe to a target page with relative url. The browsers will treat the site in iframe the same domain with your website.

  2. In your web server, using a rewrite module to redirect request from the relative url to absolute url. If you use IIS, I recommend you check on IIRF module.

JVM heap parameters

The JVM will start with memory useage at the initial heap level. If the maxheap is higher, it will grow to the maxheap size as memory requirements exceed it's current memory.

So,

  • -Xms512m -Xmx512m

JVM starts with 512 M, never resizes.

  • -Xms64m -Xmx512m

JVM starts with 64M, grows (up to max ceiling of 512) if mem. requirements exceed 64.

Capturing mobile phone traffic on Wireshark

Similarly to making your PC a wireless access point, but can be much easier, is using reverse tethering. If you happen to have an HTC phone they have a nice reverse-tethering option called "Internet pass-through", under the network/mobile network sharing settings. It routes all your traffic through your PC and you can just run Wireshark there.

Why does NULL = NULL evaluate to false in SQL server

The answers here all seem to come from a CS perspective so I want to add one from a developer perspective.

For a developer NULL is very useful. The answers here say NULL means unknown, and maybe in CS theory that's true, don't remember, it's been a while. In actual development though, at least in my experience, that happens about 1% of the time. The other 99% it is used for cases where the value is not UNKNOWN but it is KNOWN TO BE ABSENT.

For example:

  • Client.LastPurchase, for a new client. It is not unknown, it is known that he hasn't made a purchase yet.

  • When using an ORM with a Table per Class Hierarchy mapping, some values are just not mapped for certain classes.

  • When mapping a tree structure a root will usually have Parent = NULL

  • And many more...

I'm sure most developers at some point wrote WHERE value = NULL, didn't get any results, and that's how they learned about IS NULL syntax. Just look how many votes this question and the linked ones have.

SQL Databases are a tool, and they should be designed the way which is easiest for their users to understand.

How do I merge changes to a single file, rather than merging commits?

Here's what I do in these situations. It's a kludge but it works just fine for me.

  1. Create another branch based off of your working branch.
  2. git pull/git merge the revision (SHA1) which contains the file you want to copy. So this will merge all of your changes, but we are only using this branch to grab the one file.
  3. Fix up any Conflicts etc. investigate your file.
  4. checkout your working branch
  5. Checkout the file commited from your merge.
  6. Commit it.

I tried patching and my situation was too ugly for it. So in short it would look like this:

Working Branch: A Experimental Branch: B (contains file.txt which has changes I want to fold in.)

git checkout A

Create new branch based on A:

git checkout -b tempAB

Merge B into tempAB

git merge B

Copy the sha1 hash of the merge:

git log

commit 8dad944210dfb901695975886737dc35614fa94e
Merge: ea3aec1 0f76e61
Author: matthewe <[email protected]>
Date:   Wed Oct 3 15:13:24 2012 -0700

Merge branch 'B' into tempAB

Checkout your working branch:

git checkout A

Checkout your fixed-up file:

git checkout 7e65b5a52e5f8b1979d75dffbbe4f7ee7dad5017 file.txt

And there you should have it. Commit your result.

SQL WHERE ID IN (id1, id2, ..., idn)

Option 1 is the only good solution.

Why?

  • Option 2 does the same but you repeat the column name lots of times; additionally the SQL engine doesn't immediately know that you want to check if the value is one of the values in a fixed list. However, a good SQL engine could optimize it to have equal performance like with IN. There's still the readability issue though...

  • Option 3 is simply horrible performance-wise. It sends a query every loop and hammers the database with small queries. It also prevents it from using any optimizations for "value is one of those in a given list"

How to open a link in new tab (chrome) using Selenium WebDriver?

The original poster is asking on how to open a link on a new tab. So this is how I have done it in C#.

        IWebDriver driver = new ChromeDriver();
        driver.Manage().Window.Maximize();
        driver.Navigate().GoToUrl("https://microsoft.com");
        IWebElement eventlink = driver.FindElement(By.Id("uhfLogo"));
        Actions action = new Actions(driver);
        action.KeyDown(Keys.Control).MoveToElement(eventlink).Click().Perform(); 

This actually performs a Control+Click on the selected element in order to open the link in a new tab.

How do I disable log messages from the Requests library?

simple: just add requests.packages.urllib3.disable_warnings() after import requests

How to merge every two lines into one from the command line?

"ex" is a scriptable line editor that is in the same family as sed, awk, grep, etc. I think it might be what you are looking for. Many modern vi clone/successors also have a vi mode.

 ex -c "%g/KEY/j" -c "wq" data.txt

This says for each line, if it matches "KEY" perform a j oin of the following line. After that command completes (against all lines), issue a w rite and q uit.

How to iterate over a JavaScript object?

->if we iterate over a JavaScript object using and find key of array of objects

Object.keys(Array).forEach(key => {

 console.log('key',key)

})

Loop through columns and add string lengths as new columns

You need to use [[, the programmatic equivalent of $. Otherwise, for example, when i is col1, R will look for df$i instead of df$col1.

for(i in names(df)){
  df[[paste(i, 'length', sep="_")]] <- str_length(df[[i]])
}

Reset identity seed after deleting records in SQL Server

issuing 2 command can do the trick

DBCC CHECKIDENT ('[TestTable]', RESEED,0)
DBCC CHECKIDENT ('[TestTable]', RESEED)

the first reset the identity to zero , and the next will set it to the next available value -- jacob

How do I get the name of the active user via the command line in OS X?

Via here

Checking the owner of /dev/console seems to work well.

stat -f "%Su" /dev/console

Session state can only be used when enableSessionState is set to true either in a configuration

Following answer from below given path worked fine.

I found a solution that worked perfectly! Add the following to web.config:

<system.webServer>
<modules>
<!-- UrlRewriter code here -->
<remove name="Session" />
<add name="Session" type="System.Web.SessionState.SessionStateModule" preCondition="" />
</modules>
</system.webServer>

Hope this helps someone else!

"%%" and "%/%" for the remainder and the quotient

I think it is because % has often be associated with the modulus operator in many programming languages.

It is the case, e.g., in C, C++, C# and Java, and many other languages which derive their syntax from C (C itself took it from B).

How to solve SyntaxError on autogenerated manage.py?

The error is generated by using a later version of Django with an old python, probably of version 2.x.

To fix this I had to delete the .venv folder and recreate it with virtualenv -p python3 .venv && source .venv/bin/activate

How to keep two folders automatically synchronized?

Just simple modification of @silgon answer:

while true; do 
  inotifywait -r -e modify,create,delete /directory
  rsync -avz /directory /target
done

(@silgon version sometimes crashes on Ubuntu 16 if you run it in cron)

Return anonymous type results?

In C# 7 you can now use tuples!... which eliminates the need to create a class just to return the result.

Here is a sample code:

public List<(string Name, string BreedName)> GetDogsWithBreedNames()
{
    var db = new DogDataContext(ConnectString);
    var result = from d in db.Dogs
             join b in db.Breeds on d.BreedId equals b.BreedId
             select new
             {
                Name = d.Name,
                BreedName = b.BreedName
             }.ToList();

    return result.Select(r => (r.Name, r.BreedName)).ToList();
}

You might need to install System.ValueTuple nuget package though.

C#: How do you edit items and subitems in a listview?

If you're looking for "in-place" editing of a ListView's contents (specifically the subitems of a ListView in details view mode), you'll need to implement this yourself, or use a third-party control.

By default, the best you can achieve with a "standard" ListView is to set it's LabelEdit property to true to allow the user to edit the text of the first column of the ListView (assuming you want to allow a free-format text edit).

Some examples (including full source-code) of customized ListView's that allow "in-place" editing of sub-items are:

C# Editable ListView
In-place editing of ListView subitems

Execute an action when an item on the combobox is selected

The simple solution would be to use a ItemListener. When the state changes, you would simply check the currently selected item and set the text accordingly

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestComboBox06 {

    public static void main(String[] args) {
        new TestComboBox06();
    }

    public TestComboBox06() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException ex) {
                } catch (InstantiationException ex) {
                } catch (IllegalAccessException ex) {
                } catch (UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Test");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }

        });
    }

    public class TestPane extends JPanel {

        private JComboBox cb;
        private JTextField field;

        public TestPane() {
            cb = new JComboBox(new String[]{"Item 1", "Item 2"});
            field = new JTextField(12);

            add(cb);
            add(field);

            cb.setSelectedItem(null);

            cb.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    Object item = cb.getSelectedItem();
                    if ("Item 1".equals(item)) {
                        field.setText("20");
                    } else if ("Item 2".equals(item)) {
                        field.setText("30");
                    }
                }
            });
        }

    }

}

A better solution would be to create a custom object that represents the value to be displayed and the value associated with it...

Updated

Now I no longer have a 10 month chewing on my ankles, I updated the example to use a ListCellRenderer which is a more correct approach then been lazy and overriding toString

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestComboBox06 {

    public static void main(String[] args) {
        new TestComboBox06();
    }

    public TestComboBox06() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException ex) {
                } catch (InstantiationException ex) {
                } catch (IllegalAccessException ex) {
                } catch (UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Test");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }

        });
    }

    public class TestPane extends JPanel {

        private JComboBox cb;
        private JTextField field;

        public TestPane() {
            cb = new JComboBox(new Item[]{
                new Item("Item 1", "20"), 
                new Item("Item 2", "30")});
            cb.setRenderer(new ItemCelLRenderer());
            field = new JTextField(12);

            add(cb);
            add(field);

            cb.setSelectedItem(null);

            cb.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    Item item = (Item)cb.getSelectedItem();
                    field.setText(item.getValue());
                }
            });
        }

    }

    public class Item {
        private String value;
        private String text;

        public Item(String text, String value) {
            this.text = text;
            this.value = value;
        }

        public String getText() {
            return text;
        }

        public String getValue() {
            return value;
        }

    }

    public class ItemCelLRenderer extends DefaultListCellRenderer {

        @Override
        public Component getListCellRendererComponent(JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
            super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); //To change body of generated methods, choose Tools | Templates.
            if (value instanceof Item) {
                setText(((Item)value).getText());
            }
            return this;
        }

    }

}

How to configure multi-module Maven + Sonar + JaCoCo to give merged coverage report?

I was in the same situation as you, the half answers scattered throughout the Internet were quite annoying, since it seemed that many people had the same issue, but no one could be bothered to fully explain how they solved it.

The Sonar docs refer to a GitHub project with examples that are helpful. What I did to solve this was to apply the integration tests logic to regular unit tests (although proper unit tests should be submodule specific, this isn't always the case).

In the parent pom.xml, add these properties:

<properties>
    <!-- Sonar -->
    <sonar.java.coveragePlugin>jacoco</sonar.java.coveragePlugin>
    <sonar.dynamicAnalysis>reuseReports</sonar.dynamicAnalysis>
    <sonar.jacoco.reportPath>${project.basedir}/../target/jacoco.exec</sonar.jacoco.reportPath>
    <sonar.language>java</sonar.language>
</properties>

This will make Sonar pick up unit testing reports for all submodules in the same place (a target folder in the parent project). It also tells Sonar to reuse reports ran manually instead of rolling its own. We just need to make jacoco-maven-plugin run for all submodules by placing this in the parent pom, inside build/plugins:

<plugin>
    <groupId>org.jacoco</groupId>
    <artifactId>jacoco-maven-plugin</artifactId>
    <version>0.6.0.201210061924</version>
    <configuration>
        <destFile>${sonar.jacoco.reportPath}</destFile>
        <append>true</append>
    </configuration>
    <executions>
        <execution>
            <id>agent</id>
            <goals>
                <goal>prepare-agent</goal>
            </goals>
        </execution>
    </executions>
</plugin>

destFile places the report file in the place where Sonar will look for it and append makes it append to the file rather than overwriting it. This will combine all JaCoCo reports for all submodules in the same file.

Sonar will look at that file for each submodule, since that's what we pointed him at above, giving us combined unit testing results for multi module files in Sonar.

How to prevent background scrolling when Bootstrap 3 modal open on mobile browsers?

My solution...

Ver en jsfiddle

//Fix modal mobile Boostrap 3
function Show(id){
    //Fix CSS
    $(".modal-footer").css({"padding":"19px 20px 20px","margin-top":"15px","text-align":"right","border-top":"1px solid #e5e5e5"});
    $(".modal-body").css("overflow-y","auto");
    //Fix .modal-body height
    $('#'+id).on('shown.bs.modal',function(){
        $("#"+id+">.modal-dialog>.modal-content>.modal-body").css("height","auto");
        h1=$("#"+id+">.modal-dialog").height();
        h2=$(window).height();
        h3=$("#"+id+">.modal-dialog>.modal-content>.modal-body").height();
        h4=h2-(h1-h3);      
        if($(window).width()>=768){
            if(h1>h2){
                $("#"+id+">.modal-dialog>.modal-content>.modal-body").height(h4);
            }
            $("#"+id+">.modal-dialog").css("margin","30px auto");
            $("#"+id+">.modal-dialog>.modal-content").css("border","1px solid rgba(0,0,0,0.2)");
            $("#"+id+">.modal-dialog>.modal-content").css("border-radius",6);               
            if($("#"+id+">.modal-dialog").height()+30>h2){
                $("#"+id+">.modal-dialog").css("margin-top","0px");
                $("#"+id+">.modal-dialog").css("margin-bottom","0px");
            }
        }
        else{
            //Fix full-screen in mobiles
            $("#"+id+">.modal-dialog>.modal-content>.modal-body").height(h4);
            $("#"+id+">.modal-dialog").css("margin",0);
            $("#"+id+">.modal-dialog>.modal-content").css("border",0);
            $("#"+id+">.modal-dialog>.modal-content").css("border-radius",0);   
        }
        //Aply changes on screen resize (example: mobile orientation)
        window.onresize=function(){
            $("#"+id+">.modal-dialog>.modal-content>.modal-body").css("height","auto");
            h1=$("#"+id+">.modal-dialog").height();
            h2=$(window).height();
            h3=$("#"+id+">.modal-dialog>.modal-content>.modal-body").height();
            h4=h2-(h1-h3);
            if($(window).width()>=768){
                if(h1>h2){
                    $("#"+id+">.modal-dialog>.modal-content>.modal-body").height(h4);
                }
                $("#"+id+">.modal-dialog").css("margin","30px auto");
                $("#"+id+">.modal-dialog>.modal-content").css("border","1px solid rgba(0,0,0,0.2)");
                $("#"+id+">.modal-dialog>.modal-content").css("border-radius",6);               
                if($("#"+id+">.modal-dialog").height()+30>h2){
                    $("#"+id+">.modal-dialog").css("margin-top","0px");
                    $("#"+id+">.modal-dialog").css("margin-bottom","0px");
                }
            }
            else{
                //Fix full-screen in mobiles
                $("#"+id+">.modal-dialog>.modal-content>.modal-body").height(h4);
                $("#"+id+">.modal-dialog").css("margin",0);
                $("#"+id+">.modal-dialog>.modal-content").css("border",0);
                $("#"+id+">.modal-dialog>.modal-content").css("border-radius",0);   
            }
        };
    });  
    //Free event listener
    $('#'+id).on('hide.bs.modal',function(){
        window.onresize=function(){};
    });  
    //Mobile haven't scrollbar, so this is touch event scrollbar implementation
    var y1=0;
    var y2=0;
    var div=$("#"+id+">.modal-dialog>.modal-content>.modal-body")[0];
    div.addEventListener("touchstart",function(event){
        y1=event.touches[0].clientY;
    });
    div.addEventListener("touchmove",function(event){
        event.preventDefault();
        y2=event.touches[0].clientY;
        var limite=div.scrollHeight-div.clientHeight;
        var diff=div.scrollTop+y1-y2;
        if(diff<0)diff=0;
        if(diff>limite)diff=limite;
        div.scrollTop=diff;
        y1=y2;
    });
    //Fix position modal, scroll to top.    
    $('html, body').scrollTop(0);
    //Show
    $("#"+id).modal('show');
}

Psql could not connect to server: No such file or directory, 5432 error?

The same thing happened to me as I had changed something in the /etc/hosts file. After changing it back to 127.0.0.1 localhost it worked for me.

Change Bootstrap tooltip color

This is already been answered right but i think i should give my opinion too. Like cozen says this is a border, and for it to work you must specify the classes to format this in the same way that bootstrap specifies it. So, you can do this

.tooltip .tooltip-inner {background-color: #00a8c4; color: black;} 
.tooltip.top .tooltip-arrow {border-top-color: #00a8c4;}

or you can do the next one, just for the tooltip-arrow but you must add the !important, so that it overwrites the bootstrap css

.tooltip-arrow {border-top-color: #00a8c4!important;}

What is the maximum recursion depth in Python, and how to increase it?

It's to avoid a stack overflow. The Python interpreter limits the depths of recursion to help you avoid infinite recursions, resulting in stack overflows. Try increasing the recursion limit (sys.setrecursionlimit) or re-writing your code without recursion.

From the Python documentation:

sys.getrecursionlimit()

Return the current value of the recursion limit, the maximum depth of the Python interpreter stack. This limit prevents infinite recursion from causing an overflow of the C stack and crashing Python. It can be set by setrecursionlimit().

Registry key Error: Java version has value '1.8', but '1.7' is required

After the latest automatic Java update, I could not run Java from the command prompt.

My path variable had 'C:\ProgramData\Oracle\Java\javapath;'

I could not cd into 'C:\ProgramData\Oracle\Java\javapath;' from the command prompt window, since it did not exist.

I removed C:\ProgramData\Oracle\Java\javapath;' from the path variable and replaced it with 'C:\Program Files\Java\jre1.8.0_141\bin;'

Windows CMD command for accessing usb?

firstly you have to change the drive, which is allocated to your usb.

follow these step to access your pendrive using CMD. 1- type drivename follow by the colon just like k: 2- type dir it will show all the files and directory in your usb 3- now you can access any file or directory of your usb.

ERROR 1064 (42000): You have an error in your SQL syntax; Want to configure a password as root being the user

Try this one. It may be helpful:

mysql> UPDATE mysql.user SET Password = PASSWORD('pwd') WHERE User='root';

I hope it helps.

DataGridView - how to set column width?

Most of the above solutions assume that the parent DateGridView has .AutoSizeMode not equal to Fill. If you set the .AutoSizeMode for the grid to be Fill, you need to set the AutoSizeMode for each column to be None if you want to fix a particular column width (and let the other columns Fill). I found a weird MS exception regarding a null object if you change a Column Width and the .AutoSizeMode is not None first.

This works

chart.AutoSizeMode  = DataGridViewAutoSizeColumnMode.Fill;
... add some columns here
chart.Column[i].AutoSizeMode = DataGridViewAutoSizeColumnMode.None;
chart.Column[i].Width = 60;

This throws a null exception regarding some internal object regarding setting border thickness.

chart.AutoSizeMode  = DataGridViewAutoSizeColumnMode.Fill;
... add some columns here
 // chart.Column[i].AutoSizeMode = DataGridViewAutoSizeColumnMode.None;
chart.Column[i].Width = 60;

SQLite DateTime comparison

My query I did as follows:

SELECT COUNT(carSold) 
FROM cars_sales_tbl
WHERE date
BETWEEN '2015-04-01' AND '2015-04-30'
AND carType = "Hybrid"

I got the hint by @ifredy's answer. The all I did is, I wanted this query to be run in iOS, using Objective-C. And it works!

Hope someone who does iOS Development, will get use out of this answer too!

tmux status bar configuration

The man page has very detailed descriptions of all of the various options (the status bar is highly configurable). Your best bet is to read through man tmux and pay particular attention to those options that begin with status-.

So, for example, status-bg red would set the background colour of the bar.

The three components of the bar, the left and right sections and the window-list in the middle, can all be configured to suit your preferences. status-left and status-right, in addition to having their own variables (like #S to list the session name) can also call custom scripts to display, for example, system information like load average or battery time.

The option to rename windows or panes based on what is currently running in them is automatic-rename. You can set, or disable it globally with:

setw -g automatic-rename [on | off]

The most straightforward way to become comfortable with building your own status bar is to start with a vanilla one and then add changes incrementally, reloading the config as you go.1

You might also want to have a look around on github or bitbucket for other people's conf files to provide some inspiration. You can see mine here2.



1 You can automate this by including this line in your .tmux.conf:

bind R source-file ~/.tmux.conf \; display-message "Config reloaded..."

You can then test your new functionality with Ctrlb,Shiftr. tmux will print a helpful error message—including a line number of the offending snippet—if you misconfigure an option.

2 Note: I call a different status bar depending on whether I am in X or the console - I find this quite useful.

Uncaught SyntaxError: Unexpected token u in JSON at position 0

This is due to the interfering messages that come on to the page. There are multiple frames on the page which communicate with the page using window message event and object. few of them can be third party services like cookieq for managing cookies, or may be cartwire an e-com integration service.

You need to handle the onmessage event to check from where the messages are coming, and then parse the JSON accordingly.

I faced a similar problem, where one of the integration was passing a JSON object and other was passing a string starting with u

Go To Definition: "Cannot navigate to the symbol under the caret."

The following fixed this for me:

  • In Solution Explorer, right click the solution name.
  • Select "Clean Solution"

After this successfully completed, I no longer received the error, and I didn't have to close and reopen anything.

Launch an app on OS X with command line

In case your app needs to work on files (what you would normally expect to pass as: ./myApp *.jpg), you would do it like this:

open *.jpg -a myApp

Swift: Convert enum value to String?

Starting from Swift 3.0 you can

var str = String(describing: Audience.friends)

Could not find folder 'tools' inside SDK

If you get the "Failed to find DDMS files..." do this:

  1. Open eclipse
  2. Open install new software
  3. Click "Add..." -> type in (e.g.) "Android_over_HTTP" and in address put "http://dl-ssl.google.com/android/eclipse/".

Don't be alarmed that its not https, this helps to fetch stuff over http. This trick helped me to resolve the issue on MAC, I believe that this also should work on Windows / Linux

Hope this helps !

Attaching click to anchor tag in angular

<a href="javascript:void(0);" (click)="onGoToPage2()">Go to Page 2</a>

/** and /* in Java Comments

The first form is called Javadoc. You use this when you're writing formal APIs for your code, which are generated by the javadoc tool. For an example, the Java 7 API page uses Javadoc and was generated by that tool.

Some common elements you'd see in Javadoc include:

  • @param: this is used to indicate what parameters are being passed to a method, and what value they're expected to have

  • @return: this is used to indicate what result the method is going to give back

  • @throws: this is used to indicate that a method throws an exception or error in case of certain input

  • @since: this is used to indicate the earliest Java version this class or function was available in

As an example, here's Javadoc for the compare method of Integer:

/**
 * Compares two {@code int} values numerically.
 * The value returned is identical to what would be returned by:
 * <pre>
 *    Integer.valueOf(x).compareTo(Integer.valueOf(y))
 * </pre>
 *
 * @param  x the first {@code int} to compare
 * @param  y the second {@code int} to compare
 * @return the value {@code 0} if {@code x == y};
 *         a value less than {@code 0} if {@code x < y}; and
 *         a value greater than {@code 0} if {@code x > y}
 * @since 1.7
 */
public static int compare(int x, int y) {
    return (x < y) ? -1 : ((x == y) ? 0 : 1);
}

The second form is a block (multi-line) comment. You use this if you want to have multiple lines in a comment.

I will say that you'd only want to use the latter form sparingly; that is, you don't want to overburden your code with block comments that don't describe what behaviors the method/complex function is supposed to have.

Since Javadoc is the more descriptive of the two, and you can generate actual documentation as a result of using it, using Javadoc would be more preferable to simple block comments.

random number generator between 0 - 1000 in c#

Use this:

static int RandomNumber(int min, int max)
{
    Random random = new Random(); return random.Next(min, max);

}

This is example for you to modify and use in your application.

How can I put the current running linux process in background?

Suspend the process with CTRL+Z then use the command bg to resume it in background. For example:

sleep 60
^Z  #Suspend character shown after hitting CTRL+Z
[1]+  Stopped  sleep 60  #Message showing stopped process info
bg  #Resume current job (last job stopped)

More about job control and bg usage in bash manual page:

JOB CONTROL
Typing the suspend character (typically ^Z, Control-Z) while a process is running causes that process to be stopped and returns control to bash. [...] The user may then manipulate the state of this job, using the bg command to continue it in the background, [...]. A ^Z takes effect immediately, and has the additional side effect of causing pending output and typeahead to be discarded.

bg [jobspec ...]
Resume each suspended job jobspec in the background, as if it had been started with &. If jobspec is not present, the shell's notion of the current job is used.

EDIT

To start a process where you can even kill the terminal and it still carries on running

nohup [command] [-args] > [filename] 2>&1 &

e.g.

nohup /home/edheal/myprog -arg1 -arg2 > /home/edheal/output.txt 2>&1 &

To just ignore the output (not very wise) change the filename to /dev/null

To get the error message set to a different file change the &1 to a filename.

In addition: You can use the jobs command to see an indexed list of those backgrounded processes. And you can kill a backgrounded process by running kill %1 or kill %2 with the number being the index of the process.

What is this Javascript "require"?

I noticed that whilst the other answers explained what require is and that it is used to load modules in Node they did not give a full reply on how to load node modules when working in the Browser.

It is quite simple to do. Install your module using npm as you describe, and the module itself will be located in a folder usually called node_modules.

Now the simplest way to load it into your app is to reference it from your html with a script tag which points at this directory. i.e if your node_modules directory is in the root of the project at the same level as your index.html you would write this in your index.html:

<script src="node_modules/ng"></script>

That whole script will now be loaded into the page - so you can access its variables and methods directly.

There are other approaches which are more widely used in larger projects, such as a module loader like require.js. Of the two, I have not used Require myself, but I think it is considered by many people the way to go.

How to open a workbook specifying its path

You can also open a required file through a prompt, This helps when you want to select file from different path and different file.

Sub openwb()
Dim wkbk As Workbook
Dim NewFile As Variant

NewFile = Application.GetOpenFilename("microsoft excel files (*.xlsm*), *.xlsm*")

If NewFile <> False Then
Set wkbk = Workbooks.Open(NewFile)
End If
End Sub

How do I set the visibility of a text box in SSRS using an expression?

instead of this

=IIf((CountRows("ScannerStatisticsData")=0),False,True)

write only the expression when you want to hide

CountRows("ScannerStatisticsData")=0

or change the order of true and false places as below

=IIf((CountRows("ScannerStatisticsData")=0),True,False)

because the Visibility expression set up the Hidden value. that you can find above the text area as

" Set expression for: Hidden " 

How to get Linux console window width in Python

Try "blessings"

I was looking for the very same thing. It is very easy to use and offers tools for coloring, styling and positioning in the terminal. What you need is as easy as:

from blessings import Terminal

t = Terminal()

w = t.width
h = t.height

Works like a charm in Linux. (I'm not sure about MacOSX and Windows)

Download and documentation here

or you can install it with pip:

pip install blessings

how to bypass Access-Control-Allow-Origin?

It's a really bad idea to use *, which leaves you wide open to cross site scripting. You basically want your own domain all of the time, scoped to your current SSL settings, and optionally additional domains. You also want them all to be sent as one header. The following will always authorize your own domain in the same SSL scope as the current page, and can optionally also include any number of additional domains. It will send them all as one header, and overwrite the previous one(s) if something else already sent them to avoid any chance of the browser grumbling about multiple access control headers being sent.

class CorsAccessControl
{
    private $allowed = array();

    /**
     * Always adds your own domain with the current ssl settings.
     */
    public function __construct()
    {
        // Add your own domain, with respect to the current SSL settings.
        $this->allowed[] = 'http'
            . ( ( array_key_exists( 'HTTPS', $_SERVER )
                && $_SERVER['HTTPS'] 
                && strtolower( $_SERVER['HTTPS'] ) !== 'off' ) 
                    ? 's' 
                    : null )
            . '://' . $_SERVER['HTTP_HOST'];
    }

    /**
     * Optionally add additional domains. Each is only added one time.
     */
    public function add($domain)
    {
        if ( !in_array( $domain, $this->allowed )
        {
            $this->allowed[] = $domain;
        }
    /**
     * Send 'em all as one header so no browsers grumble about it.
     */
    public function send()
    {
        $domains = implode( ', ', $this->allowed );
        header( 'Access-Control-Allow-Origin: ' . $domains, true ); // We want to send them all as one shot, so replace should be true here.
    }
}

Usage:

$cors = new CorsAccessControl();

// If you are only authorizing your own domain:
$cors->send();

// If you are authorizing multiple domains:
foreach ($domains as $domain)
{
    $cors->add($domain);
}
$cors->send();

You get the idea.

Difference between Grunt, NPM and Bower ( package.json vs bower.json )

Update for mid 2016:

The things are changing so fast that if it's late 2017 this answer might not be up to date anymore!

Beginners can quickly get lost in choice of build tools and workflows, but what's most up to date in 2016 is not using Bower, Grunt or Gulp at all! With help of Webpack you can do everything directly in NPM!

Don't get me wrong people use other workflows and I still use GULP in my legacy project(but slowly moving out of it), but this is how it's done in the best companies and developers working in this workflow make a LOT of money!

Look at this template it's a very up-to-date setup consisting of a mixture of the best and the latest technologies: https://github.com/coryhouse/react-slingshot

  • Webpack
  • NPM as a build tool (no Gulp, Grunt or Bower)
  • React with Redux
  • ESLint
  • the list is long. Go and explore!

Your questions:

When I want to add a package (and check in the dependency into git), where does it belong - into package.json or into bower.json

  • Everything belongs in package.json now

  • Dependencies required for build are in "devDependencies" i.e. npm install require-dir --save-dev (--save-dev updates your package.json by adding an entry to devDependencies)

  • Dependencies required for your application during runtime are in "dependencies" i.e. npm install lodash --save (--save updates your package.json by adding an entry to dependencies)

If that is the case, when should I ever install packages explicitly like that without adding them to the file that manages dependencies (apart from installing command line tools globally)?

Always. Just because of comfort. When you add a flag (--save-dev or --save) the file that manages deps (package.json) gets updated automatically. Don't waste time by editing dependencies in it manually. Shortcut for npm install --save-dev package-name is npm i -D package-name and shortcut for npm install --save package-name is npm i -S package-name

ionic 2 - Error Could not find an installed version of Gradle either in Android Studio

Life is too short to spend it on messing with paths, etc.

Since I had Homebrew installed on the iMac, I just ran this command:

brew install gradle

The Ionic3 project started to build successfully.

how to read a text file using scanner in Java?

If you give a Scanner object a String, it will read it in as data. That is, "a.txt" does not open up a file called "a.txt". It literally reads in the characters 'a', '.', 't' and so forth.

This is according to Core Java Volume I, section 3.7.3.

If I find a solution to reading the actual paths, I will return and update this answer. The solution this text offers is to use

Scanner in = new Scanner(Paths.get("myfile.txt"));

But I can't get this to work because Path isn't recognized as a variable by the compiler. Perhaps I'm missing an import statement.

How does JPA orphanRemoval=true differ from the ON DELETE CASCADE DML clause

The moment you remove a child entity from the collection you will also be removing that child entity from the DB as well. orphanRemoval also implies that you cannot change parents; if there's a department that has employees, once you remove that employee to put it in another deparment, you will have inadvertantly removed that employee from the DB at flush/commit(whichver comes first). The morale is to set orphanRemoval to true so long as you are certain that children of that parent will not migrate to a different parent throughout their existence. Turning on orphanRemoval also automatically adds REMOVE to cascade list.

SQL permissions for roles

Unless the role was made dbo, db_owner or db_datawriter, it won't have permission to edit any data. If you want to grant full edit permissions to a single table, do this:

GRANT ALL ON table1 TO doctor 

Users in that role will have no permissions whatsoever to other tables (not even read).

Filter an array using a formula (without VBA)

Sounds like you're just trying to do a classic two-column lookup. http://www.dailydoseofexcel.com/archives/2009/04/21/vlookup-on-two-columns/

Tons of solutions for this, most simple is probably the following (which doesn't require an array formula):

=SUMPRODUCT((Lookup!A:A=Param!A1)*(Lookup!B:B=Param!B1)*(Lookup!C:C))

To translate your specific example, you would use:

=SUMPRODUCT((A1:A3=A2)*(B1:B3="B")*(C1:C3))

PHP Get Site URL Protocol - http vs https

it's the best solution of https or http use this :

<?php
$protocol = '//';  
$site_url = $protocol.$_SERVER["HTTP_HOST"];
?>

But can't display https or http, so it only use to link your site content like image, etc.

if want to redirect your site in https, add this code in .htaccess file :

<IfModule mod_rewrite.c>
 RewriteCond %{HTTP:CF-Visitor} '"scheme":"http"'
 RewriteRule ^(.*)$ https://www.your-domain.com$1 [L]
</IfModule>

Change www.your-domain.com with your dowmain name.

The requested URL /about was not found on this server

Here is another version for Wordpress, original one did not work as intended.

# BEGIN WordPress
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteRule ^index\.php$ - [END]
    RewriteCond $1 ^(index\.php)?$ [OR]
    RewriteCond $1 \.(gif|jpg|png|ico|css|js)$ [NC,OR]
    RewriteCond %{REQUEST_FILENAME} -f [OR]
    RewriteCond %{REQUEST_FILENAME} -d
    RewriteRule ^(.*)$ - [END]
    RewriteRule ^ /index.php [L]
</IfModule>
# END WordPress

Reference from this Github repository, modified a bit. After excessive testing this rule does not solve all problems. We have a Wordpress webshop, which has 40 plugins and somewhere is there a rewrite clash. I sincerely hope next version of Wordpress has no URL rewrites.


RewriteRule ^index\.php$ - [L]

Syntax Rewrite Rule

The ^ signifies start of the string, \ escapes . or it would mean any character, and $ signifies end of the string.

^index\.php$ if http(s)://hostname/index.php - do nothing [END] flag can be used to terminate not only the current round of rewrite processing but prevent any subsequent rewrite processing.


RewriteCond $1 ^(index\.php)?$ [OR]

Syntax Rewrite Condition

In RewriteCond using $1 as a test string references to captured contents of everything from the start to the end of the url http(s)://hostname/bla/bla.php. If used in substitution or condition it references to captured backreference. RewriteRule (bla)/(ble\.php)$ - for http(s)://hostname/bla/ble.php captures bla into $1 and ble.php into $2. Multiple capture groups can be accessed via $3..N.

( ) groups several characters into single unit, ? forces the match optional. [OR] flag allows you to combine rewrite conditions with a logical OR relationship as opposed to the default AND.

In short, if bla/bla.php contains index.php OR next condition


RewriteCond $1 \.(gif|jpg|png|ico|css|js)$ [NC,OR]

( ) groups several characters into single unit, | separates characters to subgroups and conditions them if any one of. [NC] flag causes the RewriteRule to be matched in case-insensitive manner.

In short, if bla/bla.php ends with any of the filetypes OR next condition


RewriteCond %{REQUEST_FILENAME} -f [OR]

Server-Variables are variables of the form %{ NAME_OF_VARIABLE } where NAME_OF_VARIABLE can be a string taken from the following list:

enter image description here

%{REQUEST_FILENAME} is full local filesystem path to the file or script matching the request, if this has already been determined by the server at the time REQUEST_FILENAME is referenced. Otherwise, such as when used in virtual host context, the same value as REQUEST_URI. Depending on the value of AcceptPathInfo, the server may have only used some leading components of the REQUEST_URI to map the request to a file.

-f check for regular file. Treats the test string as pathname and tests whether or not it exists.

In short, if bla/bla.php is a file OR next condition


RewriteCond %{REQUEST_FILENAME} -d

-d check for directory. Treats the test string as a pathname and tests whether or not it exists.

In short, if bla/bla.php is a directory


RewriteRule ^(.*)$ - [END] not as in Github [S=1]

This statement is only executed when one of the condition returned true.

. match any character * zero or more times.

The [S] flag is used to skip rules that you don't want to run. The syntax of the skip flag is [S=N], where N signifies the number of rules to skip (provided the RewriteRule matches). This can be thought of as a goto statement in your rewrite ruleset. In the following example, we only want to run the RewriteRule if the requested URI doesn't correspond with an actual file.

In short, do nothing


RewriteRule ^ /index.php [L]

The [L] flag causes mod_rewrite to stop processing the rule set. In most contexts, this means that if the rule matches, no further rules will be processed. This corresponds to the last command in Perl, or the break command in C. Use this flag to indicate that the current rule should be applied immediately without considering further rules.

In short, rewrite every path as http(s)://hostname/index.php


I fetched this little doc together from apaches.org documentation. Links below.

What is the size of column of int(11) in mysql in bytes?

As others have said, the minumum/maximum values the column can store and how much storage it takes in bytes is only defined by the type, not the length.

A lot of these answers are saying that the (11) part only affects the display width which isn't exactly true, but mostly.

A definition of int(2) with no zerofill specified will:

  • still accept a value of 100
  • still display a value of 100 when output (not 0 or 00)
  • the display width will be the width of the largest value being output from the select query.

The only thing the (2) will do is if zerofill is also specified:

  • a value of 1 will be shown 01.
  • When displaying values, the column will always have a width of the maximum possible value the column could take which is 10 digits for an integer, instead of the miniumum width required to display the largest value that column needs to show for in that specific select query, which could be much smaller.
  • The column can still take, and show a value exceeding the length, but these values will not be prefixed with 0s.

The best way to see all the nuances is to run:

CREATE TABLE `mytable` (
    `id` int(11) NOT NULL AUTO_INCREMENT,
    `int1` int(10) NOT NULL,
    `int2` int(3) NOT NULL,
    `zf1` int(10) ZEROFILL NOT NULL,
    `zf2` int(3) ZEROFILL NOT NULL,
    PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `mytable` 
(`int1`, `int2`, `zf1`, `zf2`) 
VALUES
(10000, 10000, 10000, 10000),
(100, 100, 100, 100);

select * from mytable;

which will output:

+----+-------+-------+------------+-------+
| id | int1  | int2  | zf1        | zf2   |
+----+-------+-------+------------+-------+
|  1 | 10000 | 10000 | 0000010000 | 10000 |
|  2 |   100 |   100 | 0000000100 |   100 |
+----+-------+-------+------------+-------+

This answer is tested against MySQL 5.7.12 for Linux and may or may not vary for other implementations.

Doctrine findBy 'does not equal'

There is no built-in method that allows what you intend to do.

You have to add a method to your repository, like this:

public function getWhatYouWant()
{
    $qb = $this->createQueryBuilder('u');
    $qb->where('u.id != :identifier')
       ->setParameter('identifier', 1);

    return $qb->getQuery()
          ->getResult();
}

Hope this helps.

Rotate a div using javascript

Can be pretty easily done assuming you're using jQuery and css3:

http://jsfiddle.net/S7JDU/8/

HTML:

<div id="clicker">Click Here</div>
<div id="rotating"></div>

CSS:

#clicker { 
    width: 100px; 
    height: 100px; 
    background-color: Green; 
}

#rotating { 
    width: 100px; 
    height: 100px; 
    background-color: Red; 
    margin-top: 50px; 
    -webkit-transition: all 0.3s ease-in-out;
    -moz-transition: all 0.3s ease-in-out;
    -o-transition: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
}

.rotated { 
    transform:rotate(25deg); 
    -webkit-transform:rotate(25deg); 
    -moz-transform:rotate(25deg); 
    -o-transform:rotate(25deg); 
}

JS:

$(document).ready(function() {
    $('#clicker').click(function() {
        $('#rotating').toggleClass('rotated');
    });
});

How to execute .sql script file using JDBC

Just read it and then use the preparedstatement with the full sql-file in it.

(If I remember good)

ADD: You can also read and split on ";" and than execute them all in a loop. Do not forget the comments and add again the ";"

Reason for Column is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause

Suppose I have the following table T:

a   b
--------
1   abc
1   def
1   ghi
2   jkl
2   mno
2   pqr

And I do the following query:

SELECT a, b
FROM T
GROUP BY a

The output should have two rows, one row where a=1 and a second row where a=2.

But what should the value of b show on each of these two rows? There are three possibilities in each case, and nothing in the query makes it clear which value to choose for b in each group. It's ambiguous.

This demonstrates the single-value rule, which prohibits the undefined results you get when you run a GROUP BY query, and you include any columns in the select-list that are neither part of the grouping criteria, nor appear in aggregate functions (SUM, MIN, MAX, etc.).

Fixing it might look like this:

SELECT a, MAX(b) AS x
FROM T
GROUP BY a

Now it's clear that you want the following result:

a   x
--------
1   ghi
2   pqr

setting the id attribute of an input element dynamically in IE: alternative for setAttribute method

I had the same issue! I was unable to change/set the ID attribute of elements. It worked in all other browsers but not IE. It probably isn't relevant to your problem but here is what I ended up doing:

Background

I was building an MVC site with jquery tabs. I wanted to create tabs dynamically and do an AJAX postback to the server saving the tab in the database. I wanted to use a unique identifier, in the form of an int, for the tabs so I wouldn't get in to trouble if a user created two tabs with the same name. I then used the unique ID to identify the tabs like:

<ul>
<li><a href='#{href}'>#{label}</a> <span class='ui-icon ui-icon-close'>Remove List</span></li>
<ul>

When I then implemented the remove functions on the tabs the callback uses the index, witch is 0 based. Then I had no way to sending back the unique ID to the server to trash the DB entry. The callback for the tabremove event gives the jquery event and ui parameters. With one line of code I could get the ID of the span:

var dbIndex = event.currentTarget.id;

The problem was that the span tag didn't have any ID. So in the create callback I tried to set the ID buy extracting the ID from the a href like this:

ui.tab.parentNode.id = ui.tab.href.substring(ui.tab.href.indexOf('#list-') + 6);

That worked fine in FireFox but not in IE. So I tried a few other:

//ui.tab.parentNode.setAttribute('id', ui.tab.href.substring(ui.tab.href.indexOf('#list-') + 6));
//$(ui.tab.parentNode).attr({'id':ui.tab.href.substring(ui.tab.href.indexOf('#list-') + 6)});
//ui.tab.parentNode.id.value = ui.tab.href.substring(ui.tab.href.indexOf('#list-') + 6);

None of them worked! So after a few hours of test and Googeling I gave up and draw the conclusion that IE cant set the ID attribute of an element dynamically.

As I sad this is probably not relevant to your issue but I thought I would share.

Solution

And for all of you who found this by Googleing on the tabs issue I had here is what I ended up doing in the tabsremove callback to solve the issue:

var dbIndex = event.currentTarget.offsetParent.childNodes[0].href.substring(event.currentTarget.offsetParent.childNodes[0].href.indexOf('#list-') + 6);

Probably not the sexiest solution but hey it solved the issue. If anyone have any input please share...

Simple linked list in C++

This is the most simple example I can think of in this case and is not tested. Please consider that this uses some bad practices and does not go the way you normally would go with C++ (initialize lists, separation of declaration and definition, and so on). But that are topics I can't cover here.

#include <iostream>
using namespace std;

class LinkedList{
    // Struct inside the class LinkedList
    // This is one node which is not needed by the caller. It is just
    // for internal work.
    struct Node {
        int x;
        Node *next;
    };

// public member
public:
    // constructor
    LinkedList(){
        head = NULL; // set head to NULL
    }

    // destructor
    ~LinkedList(){
        Node *next = head;
        
        while(next) {              // iterate over all elements
            Node *deleteMe = next;
            next = next->next;     // save pointer to the next element
            delete deleteMe;       // delete the current entry
        }
    }
    
    // This prepends a new value at the beginning of the list
    void addValue(int val){
        Node *n = new Node();   // create new Node
        n->x = val;             // set value
        n->next = head;         // make the node point to the next node.
                                //  If the list is empty, this is NULL, so the end of the list --> OK
        head = n;               // last but not least, make the head point at the new node.
    }

    // returns the first element in the list and deletes the Node.
    // caution, no error-checking here!
    int popValue(){
        Node *n = head;
        int ret = n->x;

        head = head->next;
        delete n;
        return ret;
    }

// private member
private:
    Node *head; // this is the private member variable. It is just a pointer to the first Node
};

int main() {
    LinkedList list;

    list.addValue(5);
    list.addValue(10);
    list.addValue(20);

    cout << list.popValue() << endl;
    cout << list.popValue() << endl;
    cout << list.popValue() << endl;
    // because there is no error checking in popValue(), the following
    // is undefined behavior. Probably the program will crash, because
    // there are no more values in the list.
    // cout << list.popValue() << endl;
    return 0;
}

I would strongly suggest you to read a little bit about C++ and Object oriented programming. A good starting point could be this: http://www.galileocomputing.de/1278?GPP=opoo

EDIT: added a pop function and some output. As you can see the program pushes 3 values 5, 10, 20 and afterwards pops them. The order is reversed afterwards because this list works in stack mode (LIFO, Last in First out)

How to picture "for" loop in block representation of algorithm

Here's a flow chart that illustrates a for loop:

Flow Chart For Loop

The equivalent C code would be

for(i = 2; i <= 6; i = i + 2) {
    printf("%d\t", i + 1);
}

I found this and several other examples on one of Tenouk's C Laboratory practice worksheets.

Is it possible to change a UIButtons background color?

This isn't as elegant as sub-classing UIButton, however if you just want something quick - what I did was create custom button, then a 1px by 1px image with the colour I'd want the button to be, and set the background of the button to that image for the highlighted state - works for my needs.

Python how to exit main function

use sys module

import sys
sys.exit()

How to add an element to Array and shift indexes?

I smell homework, so probably an ArrayList won't be allowed (?)

Instead of looking for a way to "shift indexes", maybe just build a new array:

int[] b = new int[a.length +1];

Then

  1. copy indexes form array a counting from zero up to insert position
  2. ...
  3. ...

//edit: copy values of course, not indexes

How to view the current heap size that an application is using?

You can use jconsole (standard with most JDKs) to check heap sizes of any java process.

Add two textbox values and display the sum in a third textbox automatically

try this

  function sum() {
       var txtFirstNumberValue = document.getElementById('txt1').value;
       var txtSecondNumberValue = document.getElementById('txt2').value;
       if (txtFirstNumberValue == "")
           txtFirstNumberValue = 0;
       if (txtSecondNumberValue == "")
           txtSecondNumberValue = 0;

       var result = parseInt(txtFirstNumberValue) + parseInt(txtSecondNumberValue);
       if (!isNaN(result)) {
           document.getElementById('txt3').value = result;
       }
   }

What's an object file in C?

An object file is just what you get when you compile one (or several) source file(s).

It can be either a fully completed executable or library, or intermediate files.

The object files typically contain native code, linker information, debugging symbols and so forth.

Always pass weak reference of self into block in ARC?

You don't have to always use a weak reference. If your block is not retained, but executed and then discarded, you can capture self strongly, as it will not create a retain cycle. In some cases, you even want the block to hold the self until the completion of the block so it does not deallocate prematurely. If, however, you capture the block strongly, and inside capture self, it will create a retain cycle.

Video format or MIME type is not supported

For Ubuntu 14.04

Just removed the package Oxideqt-dodecs then install flash or ubuntu restricted extras

and you are good to go!!

Getting the thread ID from a thread

GetThreadId returns the ID of a given native thread. There are ways to make it work with managed threads, I'm sure, all you need to find is the thread handle and pass it to that function.

GetCurrentThreadId returns the ID of the current thread.

GetCurrentThreadId has been deprecated as of .NET 2.0: the recommended way is the Thread.CurrentThread.ManagedThreadId property.

MySQL combine two columns and add into a new column

Add new column to your table and perfrom the query:

UPDATE tbl SET combined = CONCAT(zipcode, ' - ', city, ', ', state)

Conditional formatting based on another cell's value

I'm disappointed at how long it took to work this out.

I want to see which values in my range are outside standard deviation.

  1. Add the standard deviation calc to a cell somewhere =STDEV(L3:L32)*2
  2. Select the range to be highlighted, right click, conditional formatting
  3. Pick Format Cells if Greater than
  4. In the Value or Formula box type =$L$32 (whatever cell your stdev is in)

I couldn't work out how to put the STDEv inline. I tried many things with unexpected results.

Checking version of angular-cli that's installed?

Simple run the following commands:

ng --version 

OR

 ng -v

Output on terminal:

      / \   _ __   __ _ _   _| | __ _ _ __     / ___| |   |_ _|
   / ? \ | '_ \ / _` | | | | |/ _` | '__|   | |   | |    | |
  / ___ \| | | | (_| | |_| | | (_| | |      | |___| |___ | |
 /_/   \_\_| |_|\__, |\__,_|_|\__,_|_|       \____|_____|___|
            |___/


Angular CLI: 6.0.8
Node: 10.15.0
OS: linux x64 

Asynchronous Process inside a javascript for loop

_x000D_
_x000D_
var i = 0;_x000D_
var length = 10;_x000D_
_x000D_
function for1() {_x000D_
  console.log(i);_x000D_
  for2();_x000D_
}_x000D_
_x000D_
function for2() {_x000D_
  if (i == length) {_x000D_
    return false;_x000D_
  }_x000D_
  setTimeout(function() {_x000D_
    i++;_x000D_
    for1();_x000D_
  }, 500);_x000D_
}_x000D_
for1();
_x000D_
_x000D_
_x000D_

Here is a sample functional approach to what is expected here.

Logging framework incompatibility

SLF4J 1.5.11 and 1.6.0 versions are not compatible (see compatibility report) because the argument list of org.slf4j.spi.LocationAwareLogger.log method has been changed (added Object[] p5):

SLF4J 1.5.11:

LocationAwareLogger.log ( org.slf4j.Marker p1, String p2, int p3,
                          String p4, Throwable p5 )

SLF4J 1.6.0:

LocationAwareLogger.log ( org.slf4j.Marker p1, String p2, int p3,
                          String p4, Object[] p5, Throwable p6 )

See compatibility reports for other SLF4J versions on this page.

You can generate such reports by the japi-compliance-checker tool.

enter image description here

Convert YYYYMMDD string date to a datetime value

You should have to use DateTime.TryParseExact.

var newDate = DateTime.ParseExact("20111120", 
                                  "yyyyMMdd", 
                                   CultureInfo.InvariantCulture);

OR

string str = "20111021";
string[] format = {"yyyyMMdd"};
DateTime date;

if (DateTime.TryParseExact(str, 
                           format, 
                           System.Globalization.CultureInfo.InvariantCulture,
                           System.Globalization.DateTimeStyles.None, 
                           out date))
{
     //valid
}

Generating a PDF file from React Components

React-PDF is a great resource for this.

It is a bit time consuming converting your markup and CSS to React-PDF's format, but it is easy to understand. Exporting a PDF and from it is fairly straightforward.

To allow a user to download a PDF generated by react-PDF, use their on the fly rendering, which provides a customizable download link. When clicked, the site renders and downloads the PDF for the user.

Here's their REPL which will familiarize you with the markup and styling required. They have a download link for the PDF too, but they don't show the code for that here.

Shift elements in a numpy array

One way to do it without spilt the code into cases

with array:

def shift(arr, dx, default_value):
    result = np.empty_like(arr)
    get_neg_or_none = lambda s: s if s < 0 else None
    get_pos_or_none = lambda s: s if s > 0 else None
    result[get_neg_or_none(dx): get_pos_or_none(dx)] = default_value
    result[get_pos_or_none(dx): get_neg_or_none(dx)] = arr[get_pos_or_none(-dx): get_neg_or_none(-dx)]     
    return result

with matrix it can be done like this:

def shift(image, dx, dy, default_value):
    res = np.full_like(image, default_value)

    get_neg_or_none = lambda s: s if s < 0 else None
    get_pos_or_none = lambda s : s if s > 0 else None

    res[get_pos_or_none(-dy): get_neg_or_none(-dy), get_pos_or_none(-dx): get_neg_or_none(-dx)] = \
        image[get_pos_or_none(dy): get_neg_or_none(dy), get_pos_or_none(dx): get_neg_or_none(dx)]
    return res

What is the "assert" function?

There are three main reasons for using the assert() function over the normal if else and printf

  1. assert() function is mainly used in the debugging phase, it is tedious to write if else with a printf statement everytime you want to test a condition which might not even make its way in the final code.

  2. In large software deployments , assert comes very handy where you can make the compiler ignore the assert statements using the NDEBUG macro defined before linking the header file for assert() function.

  3. assert() comes handy when you are designing a function or some code and want to get an idea as to what limits the code will and not work and finally include an if else for evaluating it basically playing with assumptions.

jQuery issue - #<an Object> has no method

For anyone else arriving at this question:

I was performing the most simple jQuery, trying to hide an element:

('#fileselection').hide();

and I was getting the same type of error, "Uncaught TypeError: Object #fileselection has no method 'hide'

Of course, now it is obvious, but I just left off the jQuery indicator '$'. The code should have been:

$('#fileselection').hide();

This fixes the no-brainer problem. I hope this helps someone save a few minutes debugging!

Nested objects in javascript, best practices

If you know the settings in advance you can define it in a single statement:

var defaultsettings = {
                        ajaxsettings : { "ak1" : "v1", "ak2" : "v2", etc. },
                        uisettings : { "ui1" : "v1", "ui22" : "v2", etc }
                      };

If you don't know the values in advance you can just define the top level object and then add properties:

var defaultsettings = { };
defaultsettings["ajaxsettings"] = {};
defaultsettings["ajaxsettings"]["somekey"] = "some value";

Or half-way between the two, define the top level with nested empty objects as properties and then add properties to those nested objects:

var defaultsettings = {
                        ajaxsettings : {  },
                        uisettings : {  }
                      };

defaultsettings["ajaxsettings"]["somekey"] = "some value";
defaultsettings["uisettings"]["somekey"] = "some value";

You can nest as deep as you like using the above techniques, and anywhere that you have a string literal in the square brackets you can use a variable:

var keyname = "ajaxsettings";
var defaultsettings = {};
defaultsettings[keyname] = {};
defaultsettings[keyname]["some key"] = "some value";

Note that you can not use variables for key names in the { } literal syntax.

How do I type a TAB character in PowerShell?

TAB has a specific meaning in PowerShell. It's for command completion. So if you enter "getch" and then type a TAB. It changes what you typed into "GetChildItem" (it corrects the case, even though that's unnecessary).

From your question, it looks like TAB completion and command completion would overload the TAB key. I'm pretty sure the PowerShell designers didn't want that.

Could not load file or assembly 'Newtonsoft.Json, Version=9.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed' or one of its dependencies

I think AutoCAD hijacked mine. The solution which worked for me was to hijack it back. I got this from https://forums.autodesk.com/t5/navisworks-api/could-not-load-file-or-assembly-newtonsoft-json/td-p/7028055?profile.language=en - yeah, the Internet works in mysterious ways.

// in your initilizer ...
AppDomain currentDomain = AppDomain.CurrentDomain;
currentDomain.AssemblyResolve += new ResolveEventHandler(MyResolveEventHandler);

.....

private Assembly MyResolveEventHandler(object sender, ResolveEventArgs args)
{
    if (args.Name.Contains("Newtonsoft.Json"))
    {
        string assemblyFileName = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + "\\Newtonsoft.Json.dll";
        return Assembly.LoadFrom(assemblyFileName);
    }
    else
        return null;
}

How to extract text from a string using sed?

The pattern \d might not be supported by your sed. Try [0-9] or [[:digit:]] instead.

To only print the actual match (not the entire matching line), use a substitution.

sed -n 's/.*\([0-9][0-9]*G[0-9][0-9]*\).*/\1/p'

How to kill a process running on particular port in Linux?

You can know list of all ports running in system along with its details (pid, address etc.) :

netstat -tulpn

You can know details of a particular port number by providing port number in following command :

sudo netstat -lutnp | grep -w '{port_number}'

ex: sudo netstat -lutnp | grep -w '8080' Details will be provided like this :

Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name

if you want to kill a process using pid then : kill -9 {PID}

if you want to kill a process using port number : fuser -n tcp {port_number}

use sudo if you are not able to access any.

How to get a random number between a float range?

random.uniform(a, b) appears to be what your looking for. From the docs:

Return a random floating point number N such that a <= N <= b for a <= b and b <= N <= a for b < a.

See here.

Disable spell-checking on HTML textfields

Update: As suggested by a commenter (additional credit to How can I disable the spell checker on text inputs on the iPhone), use this to handle all desktop and mobile browsers.

<tag autocomplete="off" autocorrect="off" autocapitalize="off" spellcheck="false"/>

Original answer: Javascript cannot override user settings, so unless you use another mechanism other than textfields, this is not (or shouldn't be) possible.

BAT file to open CMD in current directory

There's more simple way

start /d "folder path"

How to make an unaware datetime timezone aware in python

I wrote this at Nov 22 2011 , is Pyhton 2 only , never checked if it work on Python 3

I had use from dt_aware to dt_unaware

dt_unaware = dt_aware.replace(tzinfo=None)

and dt_unware to dt_aware

from pytz import timezone
localtz = timezone('Europe/Lisbon')
dt_aware = localtz.localize(dt_unware)

but answer before is also a good solution.

How to get current date & time in MySQL?

You can use not only now(), also current_timestamp() and localtimestamp(). The main reason of incorrect display timestamp is inserting NOW() with single quotes! It didn't work for me in MySQL Workbench because of this IDE add single quotes for mysql functions and i didn't recognize it at once )

Don't use functions with single quotes like in MySQL Workbench. It doesn't work.

Spring MVC: Error 400 The request sent by the client was syntactically incorrect

My problem was the lack of BindingResult parameter after my model attribute.

 @RequestMapping(method = RequestMethod.POST, value = "/sign-up", consumes = "application/x-www-form-urlencoded")
    public ModelAndView registerUser(@Valid @ModelAttribute UserRegistrationInfo userRegistrationInfo
                                HttpServletRequest httpRequest,
                                HttpSession httpSession) { ... } 

After I added BindingResult my controller became

@RequestMapping(method = RequestMethod.POST, value = "/sign-up", consumes = "application/x-www-form-urlencoded")
    public ModelAndView registerUser(@Valid @ModelAttribute  UserRegistrationInfo userRegistrationInfo, BindingResult bindingResult,
                                HttpServletRequest httpRequest,
                                HttpSession httpSession) { ..}

Check answer @sashok_bg @sashko_bg Mersi mnogo

RESTful call in Java

I want to share my personal experience, calling a REST WS with Post JSON call:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.URL;
import java.net.URLConnection;

public class HWS {

    public static void main(String[] args) throws IOException {
        URL url = new URL("INSERT YOUR SERVER REQUEST");
        //Insert your JSON query request
        String query = "{'PARAM1': 'VALUE','PARAM2': 'VALUE','PARAM3': 'VALUE','PARAM4': 'VALUE'}";
        //It change the apostrophe char to double quote char, to form a correct JSON string
        query=query.replace("'", "\"");

        try{
            //make connection
            URLConnection urlc = url.openConnection();
            //It Content Type is so important to support JSON call
            urlc.setRequestProperty("Content-Type", "application/xml");
            Msj("Conectando: " + url.toString());
            //use post mode
            urlc.setDoOutput(true);
            urlc.setAllowUserInteraction(false);
    
            //send query
            PrintStream ps = new PrintStream(urlc.getOutputStream());
            ps.print(query);
            Msj("Consulta: " + query);
            ps.close();
    
            //get result
            BufferedReader br = new BufferedReader(new InputStreamReader(urlc.getInputStream()));
            String l = null;
            while ((l=br.readLine())!=null) {
                Msj(l);
            }
            br.close();
        } catch (Exception e){
            Msj("Error ocurrido");
            Msj(e.toString());
        }
    }
    
    private static void Msj(String texto){
        System.out.println(texto);
    }
}

ng-if, not equal to?

I don't like "hacks" but in a quick pinch for a deadline I have done this

<li ng-if="edit === false && filtered.length === 0">
    <p ng-if="group.title != 'Dispatcher News'" style="padding: 5px">No links in group.</p>
</li>

Yes, I have another inner nested ng-if, I just didn't like too many conditions on one line.

Debian 8 (Live-CD) what is the standard login and password?

Although this is an old question, I had the same question when using the Standard console version. The answer can be found in the Debian Live manual under the section 10.1 Customizing the live user. It says:

It is also possible to change the default username "user" and the default password "live".

I tried the username user and password live and it did work. If you want to run commands as root you can preface each command with sudo

Java - Getting Data from MySQL database

Easy Java method to get data from MySQL table:

/*
 * CREDIT : WWW.CODENIRVANA.IN
*/

String Data(String query){
    String get=null;
    try{

Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = (Connection)DriverManager.getConnection
("jdbc:mysql://localhost:3306/mysql","root","password");
Statement stmt = (Statement) con.createStatement();
ResultSet rs=stmt.executeQuery(query);
if (rs.next())
       {
get = rs.getString("");
        }

}
catch(Exception e){
JOptionPane.showMessageDialog (this, e.getMessage());
}
    return get;
}

Proper MIME type for OTF fonts

Try using "font/opentype".

Simplest way to throw an error/exception with a custom message in Swift 2?

In case you don't need to catch the error and you want to immediately stop the application you can use a fatalError: fatalError ("Custom message here")

Tool for sending multipart/form-data request

UPDATE: I have created a video on sending multipart/form-data requests to explain this better.


Actually, Postman can do this. Here is a screenshot

Newer version : Screenshot captured from postman chrome extension enter image description here

Another version

enter image description here

Older version

enter image description here

Make sure you check the comment from @maxkoryukov

Be careful with explicit Content-Type header. Better - do not set it's value, the Postman is smart enough to fill this header for you. BUT, if you want to set the Content-Type: multipart/form-data - do not forget about boundary field.

.htaccess mod_rewrite - how to exclude directory from rewrite rule

We used the following mod_rewrite rule:

RewriteEngine on
RewriteCond %{REQUEST_URI} !^/test/
RewriteCond %{REQUEST_URI} !^/my-folder/
RewriteRule (.*) http://www.newdomain.com/$1 [R=301,L]

This redirects (permanently with a 301 redirect) all traffic to the site to http://www.newdomain.com, except requests to resources in the /test and /my-folder directories. We transfer the user to the exact resource they requested by using the (.*) capture group and then including $1 in the new URL. Mind the spaces.

getting the reason why websockets closed with close code 1006

I've got the error while using Chrome as client and golang gorilla websocket as server under nginx proxy

And sending just some "ping" message from server to client every x second resolved problem

How do I send a file in Android from a mobile device to server using http?

the most effective method is to use android-async-http

You can use this code to upload a file:

// gather your request parameters
File myFile = new File("/path/to/file.png");
RequestParams params = new RequestParams();
try {
    params.put("profile_picture", myFile);
} catch(FileNotFoundException e) {}

// send request
AsyncHttpClient client = new AsyncHttpClient();
client.post(url, params, new AsyncHttpResponseHandler() {
    @Override
    public void onSuccess(int statusCode, Header[] headers, byte[] bytes) {
        // handle success response
    }

    @Override
    public void onFailure(int statusCode, Header[] headers, byte[] bytes, Throwable throwable) {
        // handle failure response
    }
});

Note that you can put this code directly into your main Activity, no need to create a background Task explicitly. AsyncHttp will take care of that for you!

How can I exclude a directory from Visual Studio Code "Explore" tab?

tl;dr

  1. Press Ctrl + Shift + P or Command + Shift + P on mac
  2. Type "Workspace settings".
  3. Change exclude settings either via the GUI or in settings.json:

GUI way

  1. Type "exclude" to the search bar.
  2. Click the "Add Pattern" button. Add exclude pattern in VS Code settings

Code way

  1. Click on the little {} icon at the top right corner to open the settings.json: Click brackets icon to open settings.json
  2. Add excluded folders to files.exclude. Also check out search.exclude and files.watcherExclude as they might be useful too. This snippet contains their explanations and defaults:

    {
      // Configure glob patterns for excluding files and folders. 
      // For example, the files explorer decides which files and folders to show 
      // or hide based on this setting. 
      // Read more about glob patterns [here](https://code.visualstudio.com/docs/editor/codebasics#_advanced-search-options).
      "files.exclude": {
        "**/.git": true,
        "**/.svn": true,
        "**/.hg": true,
        "**/CVS": true,
        "**/.DS_Store": true
      },
      // Configure glob patterns for excluding files and folders in searches. 
      // Inherits all glob patterns from the `files.exclude` setting.   
      // Read more about glob patterns [here](https://code.visualstudio.com/docs/editor/codebasics#_advanced-search-options).
      "search.exclude": {
        "**/node_modules": true,
        "**/bower_components": true
      },
      // Configure glob patterns of file paths to exclude from file watching. 
      // Patterns must match on absolute paths 
      // (i.e. prefix with ** or the full path to match properly). 
      // Changing this setting requires a restart. 
      // When you experience Code consuming lots of cpu time on startup, 
      // you can exclude large folders to reduce the initial load.
      "files.watcherExclude": {
        "**/.git/objects/**": true,
        "**/.git/subtree-cache/**": true,
        "**/node_modules/*/**": true
      }
    }
    

For more details on the other settings, see the official settings.json reference.

Update query PHP MySQL

Try like this in sql query, It will work fine.

$sql="UPDATE create_test set url= '$_POST[url]' WHERE test_name='$test_name';";

If you have to update multiple columns, Use like this,

$sql="UPDATE create_test set `url`= '$_POST[url]',`platform`='$_POST[platform]' WHERE test_name='$test_name';";

Generating a random hex color code with PHP

$rand = str_pad(dechex(rand(0x000000, 0xFFFFFF)), 6, 0, STR_PAD_LEFT);
echo('#' . $rand);

You can change rand() in for mt_rand() if you want, and you can put strtoupper() around the str_pad() to make the random number look nicer (although it’s not required).

It works perfectly and is way simpler than all the other methods described here :)

How can I de-install a Perl module installed via `cpan`?

There are scripts on CPAN which attempt to uninstall modules:

ExtUtils::Packlist shows sample module removing code, modrm.

Reading a file character by character in C

Either of the two should do the trick -

char *readFile(char *fileName)
{
  FILE *file;
  char *code = malloc(1000 * sizeof(char));
  char *p = code;
  file = fopen(fileName, "r");
  do 
  {
    *p++ = (char)fgetc(file);
  } while(*p != EOF);
  *p = '\0';
  return code;
}

char *readFile(char *fileName)
{
  FILE *file;
  int i = 0;
  char *code = malloc(1000 * sizeof(char));
  file = fopen(fileName, "r");
  do 
  {
    code[i++] = (char)fgetc(file);
  } while(code[i-1] != EOF);
  code[i] = '\0'
  return code;
}

Like the other posters have pointed out, you need to ensure that the file size does not exceed 1000 characters. Also, remember to free the memory when you're done using it.

Can I update a component's props in React.js?

A component cannot update its own props unless they are arrays or objects (having a component update its own props even if possible is an anti-pattern), but can update its state and the props of its children.

For instance, a Dashboard has a speed field in its state, and passes it to a Gauge child thats displays this speed. Its render method is just return <Gauge speed={this.state.speed} />. When the Dashboard calls this.setState({speed: this.state.speed + 1}), the Gauge is re-rendered with the new value for speed.

Just before this happens, Gauge's componentWillReceiveProps is called, so that the Gauge has a chance to compare the new value to the old one.

Under what circumstances can I call findViewById with an Options Menu / Action Bar item?

I am trying to obtain a handle on one of the views in the Action Bar

I will assume that you mean something established via android:actionLayout in your <item> element of your <menu> resource.

I have tried calling findViewById(R.id.menu_item)

To retrieve the View associated with your android:actionLayout, call findItem() on the Menu to retrieve the MenuItem, then call getActionView() on the MenuItem. This can be done any time after you have inflated the menu resource.

ASP.NET Core Get Json Array using IConfiguration

In ASP.NET Core 2.2 and later we can inject IConfiguration anywhere in our application like in your case, you can inject IConfiguration in HomeController and use like this to get the array.

string[] array = _config.GetSection("MyArray").Get<string[]>();

How do I determine the size of my array in C?

You can use the & operator. Here is the source code:

#include<stdio.h>
#include<stdlib.h>
int main(){

    int a[10];

    int *p; 

    printf("%p\n", (void *)a); 
    printf("%p\n", (void *)(&a+1));
    printf("---- diff----\n");
    printf("%zu\n", sizeof(a[0]));
    printf("The size of array a is %zu\n", ((char *)(&a+1)-(char *)a)/(sizeof(a[0])));


    return 0;
};

Here is the sample output

1549216672
1549216712
---- diff----
4
The size of array a is 10

Delete with "Join" in Oracle sql Query

Recently I learned of the following syntax:

DELETE (SELECT *
        FROM productfilters pf
        INNER JOIN product pr
            ON pf.productid = pr.id
        WHERE pf.id >= 200
            AND pr.NAME = 'MARK')

I think it looks much cleaner then other proposed code.

How can I run a PHP script in the background after a form is submitted?

As I know you cannot do this in easy way (see fork exec etc (don't work under windows)), may be you can reverse the approach, use the background of the browser posting the form in ajax, so if the post still work you've no wait time.
This can help even if you have to do some long elaboration.

About sending mail it's always suggest to use a spooler, may be a local & quick smtp server that accept your requests and the spool them to the real MTA or put all in a DB, than use a cron that spool the queue.
The cron may be on another machine calling the spooler as external url:

* * * * * wget -O /dev/null http://www.example.com/spooler.php

How do you automatically set the focus to a textbox when a web page loads?

You can do it easily by using jquery in this way:

<script type="text/javascript">

    $(document).ready(function () {
        $("#myTextBoxId").focus();
    });

</script>

by calling this function in $(document).ready().

It means this function will execute when the DOM is ready.

For more information about the READY function, refer to : http://api.jquery.com/ready/

In Java, how can I determine if a char array contains a particular character?

You can iterate through the array or you can convert it to a String and use indexOf.

if (new String(charArray).indexOf('q') < 0) {
    break;
}

Creating a new String is a bit wasteful, but it's probably the tersest code. You can also write a method to imitate the effect without incurring the overhead.

Open another application from your own (intent)

If you're attempting to start a SERVICE rather than activity, this worked for me:

Intent intent = new Intent();
intent.setClassName("com.example.otherapplication", "com.example.otherapplication.ServiceName");
context.startService(intent);

If you use the intent.setComponent(...) method as mentioned in other answers, you may get an "Implicit intents with startService are not safe" warning.

How to remove numbers from a string?

A secondary option would be to match and return non-digits with some expression similar to,

/\D+/g

which would likely work for that specific string in the question (1 ding ?).

Demo

Test

_x000D_
_x000D_
function non_digit_string(str) {_x000D_
 const regex = /\D+/g;_x000D_
 let m;_x000D_
_x000D_
 non_digit_arr = [];_x000D_
 while ((m = regex.exec(str)) !== null) {_x000D_
  // This is necessary to avoid infinite loops with zero-width matches_x000D_
  if (m.index === regex.lastIndex) {_x000D_
   regex.lastIndex++;_x000D_
  }_x000D_
_x000D_
_x000D_
  m.forEach((match, groupIndex) => {_x000D_
   if (match.trim() != '') {_x000D_
    non_digit_arr.push(match.trim());_x000D_
   }_x000D_
  });_x000D_
 }_x000D_
 return non_digit_arr;_x000D_
}_x000D_
_x000D_
const str = `1 ding ? 124_x000D_
12 ding ?_x000D_
123 ding ? 123`;_x000D_
console.log(non_digit_string(str));
_x000D_
_x000D_
_x000D_


If you wish to simplify/modify/explore the expression, it's been explained on the top right panel of regex101.com. If you'd like, you can also watch in this link, how it would match against some sample inputs.


RegEx Circuit

jex.im visualizes regular expressions:

enter image description here

React JSX: selecting "selected" on selected <select> option

With React 16.8. We can do this with hooks like the following example

Codesandbox link

import React, { useState } from "react";
import "./styles.css";

export default function App() {
  const options = [
    "Monty Python and the Holy Grail",
    "Monty Python's Life of Brian",
    "Monty Python's The Meaning of Life"
  ];
  const filmsByTati = [
    {
      id: 1,
      title: "Jour de fête",
      releasedYear: 1949
    },
    {
      id: 2,
      title: "Play time",
      releasedYear: 1967
    },
    {
      id: 3,
      releasedYear: 1958,
      title: "Mon Oncle"
    }
  ];
  const [selectedOption, setSelectedOption] = useState(options[0]);
  const [selectedTatiFilm, setSelectedTatiFilm] = useState(filmsByTati[0]);
  return (
    <div className="App">
      <h1>Select Example</h1>
      <select
        value={selectedOption}
        onChange={(e) => setSelectedOption(e.target.value)}
      >
        {options.map((option) => (
          <option key={option} value={option}>
            {option}
          </option>
        ))}
      </select>
      <span>Selected option: {selectedOption}</span>

      <select
        value={selectedTatiFilm}
        onChange={(e) =>
          setSelectedTatiFilm(
            filmsByTati.find(film => (film.id == e.target.value))
          )
        }
      >
        {filmsByTati.map((film) => (
          <option key={film.id} value={film.id}>
            {film.title}
          </option>
        ))}
      </select>
      <span>Selected option: {selectedTatiFilm.title}</span>
    </div>
  );
}

How to select date from datetime column?

You can use MySQL's DATE() function:

WHERE DATE(datetime) = '2009-10-20'

You could also try this:

WHERE datetime LIKE '2009-10-20%'

See this answer for info on the performance implications of using LIKE.

How to declare 2D array in bash

If each row of the matrix is the same size, then you can simply use a linear array and multiplication.

That is,

a=()
for (( i=0; i<4; ++i )); do
  for (( j=0; j<5; ++j )); do
     a[i*5+j]=0
  done
done

Then your a[2][3] = 3 becomes

a[2*5+3] = 3

This approach might be worth turning into a set of functions, but since you can't pass arrays to or return arrays from functions, you would have to use pass-by-name and sometimes eval. So I tend to file multidimensional arrays under "things bash is simply Not Meant To Do".

Python how to write to a binary file?

As of Python 3.2+, you can also accomplish this using the to_bytes native int method:

newFileBytes = [123, 3, 255, 0, 100]
# make file
newFile = open("filename.txt", "wb")
# write to file
for byte in newFileBytes:
    newFile.write(byte.to_bytes(1, byteorder='big'))

I.e., each single call to to_bytes in this case creates a string of length 1, with its characters arranged in big-endian order (which is trivial for length-1 strings), which represents the integer value byte. You can also shorten the last two lines into a single one:

newFile.write(''.join([byte.to_bytes(1, byteorder='big') for byte in newFileBytes]))

How to declare local variables in postgresql?

Postgresql historically doesn't support procedural code at the command level - only within functions. However, in Postgresql 9, support has been added to execute an inline code block that effectively supports something like this, although the syntax is perhaps a bit odd, and there are many restrictions compared to what you can do with SQL Server. Notably, the inline code block can't return a result set, so can't be used for what you outline above.

In general, if you want to write some procedural code and have it return a result, you need to put it inside a function. For example:

CREATE OR REPLACE FUNCTION somefuncname() RETURNS int LANGUAGE plpgsql AS $$
DECLARE
  one int;
  two int;
BEGIN
  one := 1;
  two := 2;
  RETURN one + two;
END
$$;
SELECT somefuncname();

The PostgreSQL wire protocol doesn't, as far as I know, allow for things like a command returning multiple result sets. So you can't simply map T-SQL batches or stored procedures to PostgreSQL functions.

How do I activate a Spring Boot profile when running from IntelliJ?

I use the Intellij Community Edition. Go to the "Run/Debug Configurations" > Runner tab > Environment variables > click button "...". Add: SPRING_PROFILES_ACTIVE = local

spring.profiles.active

jQuery / Javascript code check, if not undefined

I generally like the shorthand version:

if (!!wlocation) { window.location = wlocation; }

CSS table column autowidth

If you want to make sure that last row does not wrap and thus size the way you want it, have a look at

td {
 white-space: nowrap;
}

Angular 4 - Observable catch error

With angular 6 and rxjs 6 Observable.throw(), Observable.off() has been deprecated instead you need to use throwError

ex :

return this.http.get('yoururl')
  .pipe(
    map(response => response.json()),
    catchError((e: any) =>{
      //do your processing here
      return throwError(e);
    }),
  );

if-else statement inside jsx: ReactJS

Just Tried that:

return(
  <>
    {
      main-condition-1 && 
      main-condition-2 &&
      (sub-condition ? (<p>Hi</p>) : (<p>Hello</p>))
     }
  </>
)

Let me know what you guys think!!!

Disable and later enable all table indexes in Oracle

If you are using non-parallel direct path loads then consider and benchmark not dropping the indexes at all, particularly if the indexes only cover a minority of the columns. Oracle has a mechanism for efficient maintenance of indexes on direct path loads.

Otherwise, I'd also advise making the indexes unusable instead of dropping them. Less chance of accidentally not recreating an index.

How to create a fixed-size array of objects

The best you are going to be able to do for now is create an array with an initial count repeating nil:

var sprites = [SKSpriteNode?](count: 64, repeatedValue: nil)

You can then fill in whatever values you want.


In Swift 3.0 :

var sprites = [SKSpriteNode?](repeating: nil, count: 64)

Does it matter what extension is used for SQLite database files?

SQLite doesn't define any particular extension for this, it's your own choice. Personally, I name them with the .sqlite extension, just so there isn't any ambiguity when I'm looking at my files later.

How to get json key and value in javascript?

For getting key

var a = {"a":"1","b":"2"};
var keys = []
for(var k in a){
  keys.push(k)
}

For getting value.

var a = {"a":"1","b":"2"};
var values = []
for(var k in a){
  values.push(a[k]);
}

Add left/right horizontal padding to UILabel

Subclass UILabel and override drawTextInRect: like this:

- (void)drawTextInRect:(CGRect)rect 
{
    UIEdgeInsets insets = {0, 10, 0, 0};
    return [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}

postgresql - add boolean column to table set default

If you want an actual boolean column:

ALTER TABLE users ADD "priv_user" boolean DEFAULT false;

Rails :include vs. :joins

tl;dr

I contrast them in two ways:

joins - For conditional selection of records.

includes - When using an association on each member of a result set.

Longer version

Joins is meant to filter the result set coming from the database. You use it to do set operations on your table. Think of this as a where clause that performs set theory.

Post.joins(:comments)

is the same as

Post.where('id in (select post_id from comments)')

Except that if there are more than one comment you will get duplicate posts back with the joins. But every post will be a post that has comments. You can correct this with distinct:

Post.joins(:comments).count
=> 10
Post.joins(:comments).distinct.count
=> 2

In contract, the includes method will simply make sure that there are no additional database queries when referencing the relation (so that we don't make n + 1 queries)

Post.includes(:comments).count
=> 4 # includes posts without comments so the count might be higher.

The moral is, use joins when you want to do conditional set operations and use includes when you are going to be using a relation on each member of a collection.

need to test if sql query was successful

if you're not using the -> format, you can do this:

$a = "SQL command...";
if ($b = mysqli_query($con,$a)) {
  // results was successful
} else {
  // result was not successful
}

Best way to test exceptions with Assert to ensure they will be thrown

With most .net unit testing frameworks you can put an [ExpectedException] attribute on the test method. However this can't tell you that the exception happened at the point you expected it to. That's where xunit.net can help.

With xunit you have Assert.Throws, so you can do things like this:

    [Fact]
    public void CantDecrementBasketLineQuantityBelowZero()
    {
        var o = new Basket();
        var p = new Product {Id = 1, NetPrice = 23.45m};
        o.AddProduct(p, 1);
        Assert.Throws<BusinessException>(() => o.SetProductQuantity(p, -3));
    }

[Fact] is the xunit equivalent of [TestMethod]

How to add a .dll reference to a project in Visual Studio

Copy the downloaded DLL file in a custom folder on your dev drive, then add the reference to your project using the Browse button in the Add Reference dialog.
Be sure that the new reference has the Copy Local = True.
The Add Reference dialog could be opened right-clicking on the References item in your project in Solution Explorer

UPDATE AFTER SOME YEARS
At the present time the best way to resolve all those problems is through the
Manage NuGet packages menu command of Visual Studio 2017/2019.
You can right click on the References node of your project and select that command. From the Browse tab search for the library you want to use in the NuGet repository, click on the item if found and then Install it. (Of course you need to have a package for that DLL and this is not guaranteed to exist)

Read about NuGet here

getActivity() returns null in Fragment function

The best to get rid of this is to keep activity reference when onAttach is called and use the activity reference wherever needed, for e.g.

@Override
public void onAttach(Context context) {
    super.onAttach(activity);
    mContext = context;
}

@Override
public void onDetach() {
    super.onDetach();
    mContext = null;
}

How to install SQL Server 2005 Express in Windows 8

Microsoft says the SQL Server 2005 it's not compatible with Windows 8, but I've run it without problems (only using SP3) except the installation.

After you run the install file SQLExpr.exe look for a hidden folder recently created in the C drive. Copy the contents to another folder and cancel the installer (or use WinRar to open the file and extract the contents to a temp folder)

After that, find the file sqlncli_x64.msi in the setup folder, and run it.

Now you are ready the run the setup.exe file and install SQL server 2005 without errors

enter image description here

Regex expressions in Java, \\s vs. \\s+

Those two replaceAll calls will always produce the same result, regardless of what x is. However, it is important to note that the two regular expressions are not the same:

  • \\s - matches single whitespace character
  • \\s+ - matches sequence of one or more whitespace characters.

In this case, it makes no difference, since you are replacing everything with an empty string (although it would be better to use \\s+ from an efficiency point of view). If you were replacing with a non-empty string, the two would behave differently.

Why does pycharm propose to change method to static

I agree with the answers given here (method does not use self and therefore could be decorated with @staticmethod).

I'd like to add that you maybe want to move the method to a top-level function instead of a static method inside a class. For details see this question and the accepted answer: python - should I use static methods or top-level functions

Moving the method to a top-level function will fix the PyCharm warning, too.

Error: cannot open display: localhost:0.0 - trying to open Firefox from CentOS 6.2 64bit and display on Win7

before start make sure of installation:

yum install -y xorg-x11-server-Xorg xorg-x11-xauth xorg-x11-apps
  1. start xming or cygwin
  2. make connection with X11 forwarding (in putty don't forget to set localhost:0.0 for X display location)
  3. edit sshd.cong and restart
     cat /etc/ssh/sshd_config | grep X
                             X11Forwarding yes
                             X11DisplayOffset 10
AddressFamily inet
  1. Without the X11 forwarding, you are subjected to the X11 SECURITY and then you must: authorize the remote server to make a connection with the local X Server using a method (for instance, the xhost command) set the display environment variable to redirect the output to the X server of your local computer. In this example: 192.168.2.223 is the IP of the server 192.168.2.2 is the IP of the local computer where the x server is installed. localhost can also be used.
blablaco@blablaco01 ~
$ xhost 192.168.2.223
192.168.2.223 being added to access control list

blablaco@blablaco01 ~
$ ssh -l root 192.168.2.223
[email protected] password:
Last login: Sat May 22 18:59:04 2010 from etcetc
[root@oel5u5 ~]# export DISPLAY=192.168.2.2:0.0
[root@oel5u5 ~]# echo $DISPLAY
192.168.2.2:0.0
[root@oel5u5 ~]# xclock&

Then the xclock application must launch.

Check it on putty or mobaxterm and don't check in remote desktop Manager software. Be careful for user that sudo in.

Excel- compare two cell from different sheet, if true copy value from other cell

In your destination field you want to use VLOOKUP like so:

=VLOOKUP(Sheet1!A1:A100,Sheet2!A1:F100,6,FALSE)

VLOOKUP Arguments:

  1. The set fields you want to lookup.
  2. The table range you want to lookup up your value against. The first column of your defined table should be the column you want compared against your lookup field. The table range should also contain the value you want to display (Column F).
  3. This defines what field you want to display upon a match.
  4. FALSE tells VLOOKUP to do an exact match.

Overlapping Views in Android

Visible gallery changes visibility which is how you get the gallery over other view overlap. the Home sample app has some good examples of this technique.

The following artifacts could not be resolved: javax.jms:jms:jar:1.1

A check of ibliblio and java.net repositories reveal that jmx related jar is not present in either. I think you should manually download jms and install them locally as discussed here.

Close Bootstrap Modal

you can use;

$('#' + $('.modal.show').attr('id')).modal('hide');

How to bind a List<string> to a DataGridView control?

Thats because DataGridView looks for properties of containing objects. For string there is just one property - length. So, you need a wrapper for a string like this

public class StringValue
{
    public StringValue(string s)
    {
        _value = s;
    }
    public string Value { get { return _value; } set { _value = value; } }
    string _value;
}

Then bind List<StringValue> object to your grid. It works

How do I import a sql data file into SQL Server?

If your file is a large file, 50MB+, then I recommend you use sqlcmd, the command line utility that comes bundled with SQL Server. It is easy to use and it handles large files well. I tried it yesterday with a 22GB file using the following command:

sqlcmd -S SERVERNAME\INSTANCE_NAME -i C:\path\mysqlfile.sql -o C:\path\output_file.txt

The command above assumes that your server name is SERVERNAME, that you SQL Server installation uses the instance name INSTANCE_NAME, and that windows auth is the default auth method. After execution output.txt will contain something like the following:

...
(1 rows affected)
Processed 100 total records

(1 rows affected)
Processed 200 total records

(1 rows affected)
Processed 300 total records
...

use readfileonline.com if you need to see the contents of huge files.

UPDATE

This link provides more command line options and details such as username and password:

https://dba.stackexchange.com/questions/44101/importing-sql-server-database-from-a-sql-file

The ternary (conditional) operator in C

Since no one has mentioned this yet, about the only way to get smart printf statements is to use the ternary operator:

printf("%d item%s", count, count > 1 ? "s\n" : "\n");

Caveat: There are some differences in operator precedence when you move from C to C++ and may be surprised by the subtle bug(s) that arise thereof.

What is the Swift equivalent to Objective-C's "@synchronized"?

Another method is to create a superclass and then inherit it. This way you can use GCD more directly

class Lockable {
    let lockableQ:dispatch_queue_t

    init() {
        lockableQ = dispatch_queue_create("com.blah.blah.\(self.dynamicType)", DISPATCH_QUEUE_SERIAL)
    }

    func lock(closure: () -> ()) {
        dispatch_sync(lockableQ, closure)
    }
}


class Foo: Lockable {

    func boo() {
        lock {
            ....... do something
        }
    }

How to insert an item into a key/value pair object?

I would use the Dictionary<TKey, TValue> (so long as each key is unique).

EDIT: Sorry, realised you wanted to add it to a specific position. My bad. You could use a SortedDictionary but this still won't let you insert.

Transmitting newline character "\n"

late to the party, but if anyone comes across this, javascript has a encodeURI method

How to delete or change directory of a cloned git repository on a local computer

You can just delete that directory that you cloned the repo into, and re-clone it wherever you'd like.

React native text going off my screen, refusing to wrap. What to do?

<View style={{flexDirection:'row'}}> 
  <Text style={{flex: 1, flexWrap: 'wrap'}}> 

This will work

HTML table headers always visible at top of window when viewing a large table

This is really a tricky thing to have a sticky header on your table. I had same requirement but with asp:GridView and then I found it really thought to have sticky header on gridview. There are many solutions available and it took me 3 days trying all the solution but none of them could satisfy.

The main issue that I faced with most of these solutions was the alignment problem. When you try to make the header floating, somehow the alignment of header cells and body cells get off track.

With some solutions, I also got issue of getting header overlapped to first few rows of body, which cause body rows getting hidden behind the floating header.

So now I had to implement my own logic to achieve this, though I also not consider this as perfect solution but this could also be helpful for someone,

Below is the sample table.

<div class="table-holder">
        <table id="MyTable" cellpadding="4" cellspacing="0" border="1px" class="customerTable">
            <thead>
                <tr><th>ID</th><th>First Name</th><th>Last Name</th><th>DOB</th><th>Place</th></tr>
            </thead>
            <tbody>
                <tr><td>1</td><td>Customer1</td><td>LastName</td><td>1-1-1</td><td>SUN</td></tr>
                <tr><td>2</td><td>Customer2</td><td>LastName</td><td>2-2-2</td><td>Earth</td></tr>
                <tr><td>3</td><td>Customer3</td><td>LastName</td><td>3-3-3</td><td>Mars</td></tr>
                <tr><td>4</td><td>Customer4</td><td>LastName</td><td>4-4-4</td><td>Venus</td></tr>
                <tr><td>5</td><td>Customer5</td><td>LastName</td><td>5-5-5</td><td>Saturn</td></tr>
                <tr><td>6</td><td>Customer6</td><td>LastName</td><td>6-6-6</td><td>Jupitor</td></tr>
                <tr><td>7</td><td>Customer7</td><td>LastName</td><td>7-7-7</td><td>Mercury</td></tr>
                <tr><td>8</td><td>Customer8</td><td>LastName</td><td>8-8-8</td><td>Moon</td></tr>
                <tr><td>9</td><td>Customer9</td><td>LastName</td><td>9-9-9</td><td>Uranus</td></tr>
                <tr><td>10</td><td>Customer10</td><td>LastName</td><td>10-10-10</td><td>Neptune</td></tr>
            </tbody>
        </table>
    </div>

Note: The table is wrapped into a DIV with class attribute equal to 'table-holder'.

Below is the JQuery script that I added in my html page header.

<script src="../Scripts/jquery-1.7.2.min.js" type="text/javascript"></script>
<script src="../Scripts/jquery-ui.min.js" type="text/javascript"></script>
<script type="text/javascript">
    $(document).ready(function () {
        //create var for table holder
        var originalTableHolder = $(".table-holder");
        // set the table holder's with
        originalTableHolder.width($('table', originalTableHolder).width() + 17);
        // Create a clone of table holder DIV
        var clonedtableHolder = originalTableHolder.clone();

        // Calculate height of all header rows.
        var headerHeight = 0;
        $('thead', originalTableHolder).each(function (index, element) {
            headerHeight = headerHeight + $(element).height();
        });

        // Set the position of cloned table so that cloned table overlapped the original
        clonedtableHolder.css('position', 'relative');
        clonedtableHolder.css('top', headerHeight + 'px');

        // Set the height of cloned header equal to header height only so that body is not visible of cloned header
        clonedtableHolder.height(headerHeight);
        clonedtableHolder.css('overflow', 'hidden');

        // reset the ID attribute of each element in cloned table
        $('*', clonedtableHolder).each(function (index, element) {
            if ($(element).attr('id')) {
                $(element).attr('id', $(element).attr('id') + '_Cloned');
            }
        });

        originalTableHolder.css('border-bottom', '1px solid #aaa');

        // Place the cloned table holder before original one
        originalTableHolder.before(clonedtableHolder);
    });
</script>

and at last below is the CSS class for bit of coloring purpose.

.table-holder
{
    height:200px;
    overflow:auto;
    border-width:0px;    
}

.customerTable thead
{
    background: #4b6c9e;        
    color:White;
}

So the whole idea of this logic is to place the table into a table holder div and create clone of that holder at client side when page loaded. Now hide the body of table inside clone holder and position the remaining header part over to original header.

Same solution also works for asp:gridview, you need to add two more steps to achieve this in gridview,

  1. In OnPrerender event of gridview object in your web page, set the table section of header row equal to TableHeader.

    if (this.HeaderRow != null)
    {
        this.HeaderRow.TableSection = TableRowSection.TableHeader;
    }
    
  2. And wrap your grid into <div class="table-holder"></div>.

Note: if your header has clickable controls then you may need to add some more jQuery script to pass the events raised in cloned header to original header. This code is already available in jQuery sticky-header plugin create by jmosbech

Cannot find module '@angular/compiler'

I just run npm install and then ok.

Divide a number by 3 without using *, /, +, -, % operators

Solution using fma() library function, works for any positive number:

#include <stdio.h>
#include <math.h>

int main()
{
    int number = 8;//Any +ve no.
    int temp = 3, result = 0;
    while(temp <= number){
        temp = fma(temp, 1, 3); //fma(a, b, c) is a library function and returns (a*b) + c.
        result = fma(result, 1, 1);
    } 
    printf("\n\n%d divided by 3 = %d\n", number, result);
}

See my another answer.

How to change letter spacing in a Textview?

Since API 21 there is an option set letter spacing. You can call method setLetterSpacing or set it in XML with attribute letterSpacing.

Stopping a JavaScript function when a certain condition is met

The return statement exits a function from anywhere within the function:

function something(x)
{
    if (x >= 10)
        // this leaves the function if x is at least 10.
        return;

    // this message displays only if x is less than 10.
    alert ("x is less than 10!");
}

How to deal with http status codes other than 200 in Angular 2

Include required imports and you can make ur decision in handleError method Error status will give the error code

import { HttpClient, HttpErrorResponse } from '@angular/common/http';
import {Observable, throwError} from "rxjs/index";
import { catchError, retry } from 'rxjs/operators';
import {ApiResponse} from "../model/api.response";
import { TaxType } from '../model/taxtype.model'; 

private handleError(error: HttpErrorResponse) {
if (error.error instanceof ErrorEvent) {
  // A client-side or network error occurred. Handle it accordingly.
  console.error('An error occurred:', error.error.message);
} else {
  // The backend returned an unsuccessful response code.
  // The response body may contain clues as to what went wrong,
  console.error(
    `Backend returned code ${error.status}, ` +
    `body was: ${error.error}`);
}
// return an observable with a user-facing error message
return throwError(
  'Something bad happened; please try again later.');
  };

  getTaxTypes() : Observable<ApiResponse> {
return this.http.get<ApiResponse>(this.baseUrl).pipe(
  catchError(this.handleError)
);
  }

async await return Task

Adding the async keyword is just syntactic sugar to simplify the creation of a state machine. In essence, the compiler takes your code;

public async Task MethodName()
{
     return null;
}

And turns it into;

public Task MethodName()
{
     return Task.FromResult<object>(null);
}

If your code has any await keywords, the compiler must take your method and turn it into a class to represent the state machine required to execute it. At each await keyword, the state of variables and the stack will be preserved in the fields of the class, the class will add itself as a completion hook to the task you are waiting on, then return.

When that task completes, your task will be executed again. So some extra code is added to the top of the method to restore the state of variables and jump into the next slab of your code.

See What does async & await generate? for a gory example.

This process has a lot in common with the way the compiler handles iterator methods with yield statements.

How to Fill an array from user input C#?

string []answer = new string[10];
for(int i = 0;i<answer.length;i++)
{
    answer[i]= Console.ReadLine();
}

Qt Creator color scheme

I found some trick for your problem! Here you can see it: Habrahabr -- Redesigning Qt Creator by your hands (russian lang.)

According to that article, that trick is kind of not so dirty, but "hack" (probably it wouldn't harm your system, but it can leave some artifacts on your interface).

You don't need to patch something (there is possibility, but I don't recommend).

Main idea is to use stylesheet like this stylesheet.css:

// on Linux
qtcreator -stylesheet='.qt-stylesheet.css' 
// on Windows
[pathToQt]\QtCreator\bin\qtcreator.exe -stylesheet [pathToStyleSheet]

To get such effect: QtCreator before and after

To customize by your needs, you may need to read documentation: Qt Style Sheets Reference, Qt Style Sheets Examples and so on.

This wiki page is dedicated to custom Qt Creator styling.

P.S. If you'll got better stylesheet, share it, I'll be happy! :)


UPD (10.12.2014): Hopefully, now we can close this topic. Thanks, Simon G., Things have changed once again. Users may use custom themes since QtCreator 3.3. So hacky stylesheets are no longer needed.

Everyone can take a look at todays update: Qt 5.4 released. There you can find information that Qt 5.4, also comes with a brand new version of Qt Creator 3.3. Just take a look at official video at Youtube.

So, to apply dark theme you need go to "Tools" -> "Options" -> "Environment" -> "General" tab, and there you need to change "Theme".

See more information about its configuring here: Configuring Qt Creator.

how to convert java string to Date object

The concise version:

String dateStr = "06/27/2007";
DateFormat formatter = new SimpleDateFormat("MM/dd/yyyy");
Date startDate = (Date)formatter.parse(dateStr);  

Add a try/catch block for a ParseException to ensure the format is a valid date.

Convert DataSet to List

                DataSet ds = new DataSet();
                ds = obj.getXmlData();// get the multiple table in dataset.

                Employee objEmp = new Employee ();// create the object of class Employee 
                List<Employee > empList = new List<Employee >();
                int table = Convert.ToInt32(ds.Tables.Count);// count the number of table in dataset
                for (int i = 1; i < table; i++)// set the table value in list one by one
                {
                    foreach (DataRow dr in ds.Tables[i].Rows)
                    {
                        empList.Add(new Employee { Title1 = Convert.ToString(dr["Title"]), Hosting1 = Convert.ToString(dr["Hosting"]), Startdate1 = Convert.ToString(dr["Startdate"]), ExpDate1 = Convert.ToString(dr["ExpDate"]) });
                    }
                }
                dataGridView1.DataSource = empList;

enter image description here

mysql data directory location

If you are using Homebrew to install [email protected], the location is

/usr/local/Homebrew/var/mysql

I don't know if the location is the same for other versions.

How can I format date by locale in Java?

SimpleDateFormat has a constructor which takes the locale, have you tried that?

http://java.sun.com/javase/6/docs/api/java/text/SimpleDateFormat.html

Something like new SimpleDateFormat("your-pattern-here", Locale.getDefault());

How do I write stderr to a file while using "tee" with a pipe?

why not simply:

./aaa.sh 2>&1 | tee -a log

This simply redirects stderr to stdout, so tee echoes both to log and to screen. Maybe I'm missing something, because some of the other solutions seem really complicated.

Note: Since bash version 4 you may use |& as an abbreviation for 2>&1 |:

./aaa.sh |& tee -a log

Swift - Integer conversion to Hours/Minutes/Seconds

NSTimeInterval is Double do do it with extension. Example:

extension Double {

    var formattedTime: String {

        var formattedTime = "0:00"

        if self > 0 {

            let hours = Int(self / 3600)
            let minutes = Int(truncatingRemainder(dividingBy: 3600) / 60)

            formattedTime = String(hours) + ":" + (minutes < 10 ? "0" + String(minutes) : String(minutes))
        }

        return formattedTime
    }
}

Is it wrong to place the <script> tag after the </body> tag?

Yes. But if you do add the code outside it most likely will not be the end of the world since most browsers will fix it, but it is still a bad practice to get into.

Effectively use async/await with ASP.NET Web API

I am not very sure whether it will make any difference in performance of my API.

Bear in mind that the primary benefit of asynchronous code on the server side is scalability. It won't magically make your requests run faster. I cover several "should I use async" considerations in my article on async ASP.NET.

I think your use case (calling other APIs) is well-suited for asynchronous code, just bear in mind that "asynchronous" does not mean "faster". The best approach is to first make your UI responsive and asynchronous; this will make your app feel faster even if it's slightly slower.

As far as the code goes, this is not asynchronous:

public Task<BackOfficeResponse<List<Country>>> ReturnAllCountries()
{
  var response = _service.Process<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
  return Task.FromResult(response);
}

You'd need a truly asynchronous implementation to get the scalability benefits of async:

public async Task<BackOfficeResponse<List<Country>>> ReturnAllCountriesAsync()
{
  return await _service.ProcessAsync<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
}

Or (if your logic in this method really is just a pass-through):

public Task<BackOfficeResponse<List<Country>>> ReturnAllCountriesAsync()
{
  return _service.ProcessAsync<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
}

Note that it's easier to work from the "inside out" rather than the "outside in" like this. In other words, don't start with an asynchronous controller action and then force downstream methods to be asynchronous. Instead, identify the naturally asynchronous operations (calling external APIs, database queries, etc), and make those asynchronous at the lowest level first (Service.ProcessAsync). Then let the async trickle up, making your controller actions asynchronous as the last step.

And under no circumstances should you use Task.Run in this scenario.

PHP include relative path

function relativepath($to){
    $a=explode("/",$_SERVER["PHP_SELF"] );
    $index= array_search("$to",$a);
    $str=""; 
    for ($i = 0; $i < count($a)-$index-2; $i++) {
        $str.= "../";
    }
    return $str;
    }

Here is the best solution i made about that, you just need to specify at which level you want to stop, but the problem is that you have to use this folder name one time.

How to use particular CSS styles based on screen size / device

@media queries serve this purpose. Here's an example:

@media only screen and (max-width: 991px) and (min-width: 769px){
 /* CSS that should be displayed if width is equal to or less than 991px and larger 
  than 768px goes here */
}

@media only screen and (max-width: 991px){
 /* CSS that should be displayed if width is equal to or less than 991px goes here */
}

How do I check if a SQL Server text column is empty?

I wanted to have a predefined text("No Labs Available") to be displayed if the value was null or empty and my friend helped me with this:

StrengthInfo = CASE WHEN ((SELECT COUNT(UnitsOrdered) FROM [Data_Sub_orders].[dbo].[Snappy_Orders_Sub] WHERE IdPatient = @PatientId and IdDrugService = 226)> 0)
                            THEN cast((S.UnitsOrdered) as varchar(50))
                    ELSE 'No Labs Available'
                    END

Commenting out a set of lines in a shell script

What if you just wrap your code into function?

So this:

cd ~/documents
mkdir test
echo "useless script" > about.txt

Becomes this:

CommentedOutBlock() {
  cd ~/documents
  mkdir test
  echo "useless script" > about.txt
}

Could not commit JPA transaction: Transaction marked as rollbackOnly

As explained @Yaroslav Stavnichiy if a service is marked as transactional spring tries to handle transaction itself. If any exception occurs then a rollback operation performed. If in your scenario ServiceUser.method() is not performing any transactional operation you can use @Transactional.TxType annotation. 'NEVER' option is used to manage that method outside transactional context.

Transactional.TxType reference doc is here.

How to overcome TypeError: unhashable type: 'list'

    python 3.2

    with open("d://test.txt") as f:
              k=(((i.split("\n"))[0].rstrip()).split() for i in f.readlines())
              d={}
              for i,_,v in k:
                      d.setdefault(i,[]).append(v)

Execute JavaScript code stored as a string

Use eval().

W3 Schools tour of eval. Site has some usable examples of eval. The Mozilla documentation covers this in detail.

You will probably get a lot of warnings about using this safely. do NOT allow users to inject ANYTHING into eval() as it is a huge security issue.

You'll also want to know that eval() has a different scope.

Use a LIKE statement on SQL Server XML Datatype

Another option is to search the XML as a string by converting it to a string and then using LIKE. However as a computed column can't be part of a WHERE clause you need to wrap it in another SELECT like this:

SELECT * FROM
    (SELECT *, CONVERT(varchar(MAX), [COLUMNA]) as [XMLDataString] FROM TABLE) x
WHERE [XMLDataString] like '%Test%'

Replace part of a string in Python?

Use the replace() method on string:

>>> stuff = "Big and small"
>>> stuff.replace( " and ", "/" )
'Big/small'

The tilde operator in Python

The only time I've ever used this in practice is with numpy/pandas. For example, with the .isin() dataframe method.

In the docs they show this basic example

>>> df.isin([0, 2])
        num_legs  num_wings
falcon      True       True
dog        False       True

But what if instead you wanted all the rows not in [0, 2]?

>>> ~df.isin([0, 2])
        num_legs  num_wings
falcon     False       False
dog        True        False

How to convert an Object {} to an Array [] of key-value pairs in JavaScript

This is my simple barebone implementation:

let obj = {
  "1": 5,
  "2": 7,
  "3": 0,
  "4": 0,
  "5": 0,
  "6": 0,
  "7": 0,
  "8": 0,
  "9": 0,
  "10": 0,
  "11": 0,
  "12": 0
};    

const objectToArray = obj => {
      let sol = [];
      for (key in obj) {
        sol.push([key, obj[key]]);
      }
      return sol;
    };

objectToArray(obj)

Google Chrome Printing Page Breaks

Beware of CSS : display:inline-block when printing.

None of the CCS property to go to next page would work for me in Chrome and Firefox if my table was inside a div with the style display:inline-block

For example, the following doesn't work :

<div style='display:inline-block'>
  <table style='page-break-before:always'>
    ...
  </table>
  <table style='page-break-before:always'>
    ...
  </table>
</div>

But the following work :

<div>
  <table style='page-break-before:always'>
    ...
  </table>
  <table style='page-break-before:always'>
    ...
  </table>
</div>