Functionality is supposed to be broken in jQuery 1.5.

Since jQuery 1.5.1 you should use xhrFields param.

    $.ajaxSetup({
        type: &quot;POST&quot;,
        data: {},
        dataType: &#39;json&#39;,
        xhrFields: {
           withCredentials: true
        },
        crossDomain: true
    });

Docs: http://api.jquery.com/jQuery.ajax/

Reported bug: http://bugs.jquery.com/ticket/8146

You can use the [`beforeSend`][1] callback to set additional parameters (The `XMLHTTPRequest` object is passed to it as its only parameter). 

Just so you know, this type of cross-domain request will not work in a normal site scenario and not with any other browser. I don&#39;t even know what security limitations FF 3.5 imposes as well, just so you don&#39;t beat your head against the wall for nothing:

    $.ajax({
        url: &#39;http://bar.other&#39;,
        data: { whatever:&#39;cool&#39; },
        type: &#39;GET&#39;,
        beforeSend: function(xhr){
           xhr.withCredentials = true;
        }
    });

One more thing to beware of, is that jQuery is setup to normalize browser differences. You may find that further limitations are imposed by the jQuery library that prohibit this type of functionality.


  [1]: http://api.jquery.com/jQuery.ajax/

In jQuery 3 and perhaps earlier versions, the following simpler config also works for individual requests:

    $.ajax(
            &#39;https://foo.bar.com,
            {
                dataType: &#39;json&#39;,
                xhrFields: {
                    withCredentials: true
                },
                success: successFunc
            }
        );

The full error I was getting in Firefox Dev Tools -&gt; Network tab (in the Security tab for an individual request) was:

&gt; An error occurred during a connection to foo.bar.com.SSL peer was
&gt; unable to negotiate an acceptable set of security parameters.Error
&gt; code: SSL_ERROR_HANDSHAKE_FAILURE_ALERT

I am not able to understand the point of `Option[T]` class in Scala. I mean, I am not able to see any advanages of `None` over `null`.

For example, consider the code:

    object Main{
      class Person(name: String, var age: int){
        def display = println(name+&quot; &quot;+age)
      }

      def getPerson1: Person = {
        // returns a Person instance or null
      }

      def getPerson2: Option[Person] = {
        // returns either Some[Person] or None
      }

      def main(argv: Array[String]): Unit = {
        val p = getPerson1
        if (p!=null) p.display
        
        getPerson2 match{
          case Some(person) =&gt; person.display
          case None =&gt; /* Do nothing */
        }
      }
    }
    
Now suppose, the method `getPerson1` returns `null`, then the call made to `display` on first line of `main` is bound to fail with `NPE`. Similarly if `getPerson2` returns `None`, the `display` call will again fail with some similar error.

If so, then why does Scala complicate things by introducing a new value wrapper (`Option[T]`) instead of following a simple approach used in Java?

**UPDATE:**

I have edited my code as per [@Mitch][2]&#39;s suggestion. I am still not able to see any particular advantage of `Option[T]`. I have to test for the exceptional `null` or `None` in both cases. :(

If I have understood correctly from [@Michael&#39;s reply][3], is the only advantage of `Option[T]` is that it explicitly tells the programmer that *this method could return None*? Is this the only reason behind this design choice?

  [1]: http://en.wikipedia.org/wiki/Currying
  [2]: https://stackoverflow.com/users/164075
  [3]: https://stackoverflow.com/questions/2079170/why-optiont/2079247#2079247


What is the point of the class Option[T]?

Is there any keyboard shortcut to select a word? Or may be it can be assigned some how?

Shortcut key to select word in Eclipse

According to [Requests with credentials][1], Firefox will only send credentials along with cross-domain posts if 

`invocation.withCredentials = &quot;true&quot;;` 

is set… But it doesn&#39;t seem like jQuery&#39;s Ajax API provides any mechanism for this.

Is there something I&#39;ve missed? Is there some other way I can do it?


  [1]: https://developer.mozilla.org/en/HTTP_access_control#Requests_with_credentials

Sending credentials with cross-domain posts?

According to <a href="https://developer.mozilla.org/en/HTTP_access_control#Requests_with_credentials" target="_blank" rel="noopener noreferrer">Requests with credentials</a>, Firefox will only send credentials along with cross-domain posts if
<code>invocation.withCredentials = "true";</code>
is set… But it doesn't seem like jQuery's Ajax API provides any mechanism for this.
Is there something I've missed? Is there some other way I can do it?

I am trying to use the jQuery POST function but it is handling the request in AJAX style. I mean it&#39;s not actually going to the page I am telling it to go.

    $(&quot;#see_comments&quot;).click(function() {
        $.post(
            &quot;comments.php&quot;, 
            {aid: imgnum}, 
        	function (data) {

            }
        );
    });
    		
This function should go to *comments.php* page with the aid value in hand. It&#39;s posting fine but not redirecting to *comments.php*.

---
**@Doug Neiner** Clarification:

1. I have 15 links (images). I click on a link and it loads my JavaScript. The script knows what `imgnum` I opened. This `imgnum` I want in the *comments.php*. I have to use this JavaScript and no other means can do the trick. The JavaScript is mandatory

2. Your method successfully POSTs the aid value. But in the *comments.php* when I try to echo that value, it displays nothing. 

3. I am using Firebug. In the Console, it shows the echo REQUEST I made in Step (2) successfully. 

Non-AJAX jQuery POST request

Is there any way to determine the pixel length of a string in jQuery/JavaScript?

Determine Pixel Length of String in Javascript/jQuery?

I&#39;m looking for a way to automatically &quot;click&quot; an item when the page loads. 

I&#39;ve tried using

    $(&quot;document&quot;).ready(function() {
        $(&quot;ul.galleria li:first-child img&quot;).trigger(&#39;click&#39;);
    });

but it doesn&#39;t seem to work? However, when I enter `$(&quot;ul.galleria li:first-child img&quot;).trigger(&#39;click&#39;);` into Firebug&#39;s console and run the script, it works.

Can the trigger event be used on load?

How to trigger click on page load?

I have been programming with OOP languages for over 10 years but I&#39;m learning JavaScript now and it&#39;s the first time I&#39;ve encountered prototype-based inheritance. I tend to learn fastest by studying good code. What&#39;s a well-written example of a JavaScript application (or library) that properly uses prototypal inheritance? And can you describe (briefly) how/where prototypal inheritance is used, so I know where to start reading?

Good Example of JavaScript&#39;s Prototype-Based Inheritance

I have a webpage with an IFrame and a Button, once the button is pressed I need the IFrame to be refreshed. Is this possible, if so how? I searched and could not find any answers.

How to refresh an IFrame using Javascript?

In my aspx page I have a thumbnail image `&lt;img&gt;`. When the user clicks on that image I would like a popup to show that blocks out the rest of the UI with the larger (full) version of the image.

Are there any plugins that can do this?

jQuery: How can I show an image popup onclick of the thumbnail?

I&#39;m trying to find the value of the submit button that triggered the form to submit

    $(&quot;form&quot;).submit(function() {
           
    });

I could possibly fire a $(&quot;input[type=submit]&quot;).click() event for each button and set some variable, but that seems less elegant than some how pulling the button off of the the form on submit.

How can I get the button that caused the submit from the form submit event?

Did I not get enough sleep or what? This following code

    var frame=document.getElementById(&quot;viewer&quot;);
    frame.width=100;
    frame.height=100;

    var ctx=frame.getContext(&quot;2d&quot;);
    var img=new Image();
    img.src=&quot;http://www.ansearch.com/images/interface/item/small/image.png&quot;
    
    img.onload=function() {
        // draw image
        ctx.drawImage(img, 0, 0)
      
        // Here&#39;s where the error happens:
        window.open(frame.toDataURL(&quot;image/png&quot;));
    }

is throwing this error: 

    SECURITY_ERR: DOM Exception 18

There&#39;s no way this shouldn&#39;t work! Can anyone explain this, please?

Why does canvas.toDataURL() throw a security exception?

I have two webapps WebApp1 and WebApp2 in two different domains.

1. I am setting a cookie in WebApp1 in the HttpResponse.
2. How to read the same cookie from HttpRequest in WebApp2?

I know it sounds weird because cookies are specific to a given domain, and we can&#39;t access them from different domains; I&#39;ve however heard of CROSS-DOMAIN cookies which can be shared across multiple  webapps. How to implement this requirement using CROSS-DOMAIN cookies?

Note: I am trying this with J2EE webapps          

Cross-Domain Cookies

I am doing a cross domain request using `$.ajax`. It works on Firefox and Chrome, but does not issue a call on IE 7 or 8. Can anyone tell me what&#39;s wrong with the following?

1. I have used JSON and JSONP (which I stopped using, due to some custom restrictions).
2. I am already using `Allow-access-control-origin` header on my site. (Without those, Chrome and Firefox were not making successful requests.)
3. I have already tried &lt;https://developer.mozilla.org/en/http_access_control&gt;

### Code:
    $.ajax({
        type: &#39;GET&#39;,
        url: &quot;http://anotherdomain.com/Service/GetControl?id=&quot; + zoneID,
        cache: false,
        contentType: &quot;application/x-www-form-urlencoded&quot;,
        async: false,
        beforeSend: function (request) {
            //alert(&#39;before send&#39;);
            //request.setRequestHeader(&quot;X-Requested-With&quot;, &quot;XMLHttpRequest&quot;);
            //request.setRequestHeader(&quot;X-PINGOTHER&quot;, &quot;pingpong&quot;);
        } ,
        success: function (data, status) {
            //alert(&quot;Data returned :&quot; + data);
            //alert(&quot;Status :&quot; + status);
            if (status == &quot;success&quot; &amp;&amp; data != &quot;&quot;)
                $(&quot;#&quot; + div.id).append(data);
            else
                $(&quot;#&quot; + div.id).attr(&quot;style&quot;, &quot;display:none;&quot;);
        },
        error: function (XMLHttpRequest, textStatus, errorThrown) {
            alert(textStatus);
            alert(errorThrown);
        }
    });

I have tried various tips present on multiple sites, but no luck yet.


Jquery $.ajax fails in IE on cross domain calls

Okay, I have a page on and on this page I have an iframe.  What I need to do is on the iframe page, find out what the URL of the main page is. 

I have searched around and I know that this is not possible if my iframe page is on a different domain, as that is cross-site scripting. But everywhere I&#39;ve read says that if the iframe page is on the same domain as the parent page, it should work if I do for instance:

    parent.document.location

&lt;!-- --&gt;

    parent.window.document.location

&lt;!-- --&gt;

    parent.window.location

&lt;!-- --&gt;

    parent.document.location.href

... or other similar combos, as there seems to be multiple ways to get the same info. 

Anyways, so here&#39;s the problem.  My iframe is on the same domain as the main page, but it is not on the same SUB domain.  So for instance I have

&gt;http:// www.mysite.com/pageA.html

and then my iframe URL is 

&gt;http:// qa-www.mysite.com/pageB.html

When I try to grab the URL from `pageB.html` (the iframe page), I keep getting the same access denied error.  So it appears that even sub-domains count as cross-site scripting, is that correct, or am I doing something wrong?

Access parent URL from iframe

Here are two pages, test.php and testserver.php.

**test.php**

    &lt;script src=&quot;scripts/jq.js&quot; type=&quot;text/javascript&quot;&gt;&lt;/script&gt;
    &lt;script&gt;
        $(function() {
            $.ajax({url:&quot;testserver.php&quot;,
                success:function() {
                    alert(&quot;Success&quot;);
                },
                error:function() {
                    alert(&quot;Error&quot;);
                },
                dataType:&quot;json&quot;,
                type:&quot;get&quot;
            }
        )})
    &lt;/script&gt;

**testserver.php**

    &lt;?php
    $arr = array(&quot;element1&quot;,
                 &quot;element2&quot;,
                 array(&quot;element31&quot;,&quot;element32&quot;));
    $arr[&#39;name&#39;] = &quot;response&quot;;
    echo json_encode($arr);
    ?&gt;

Now my problem: when both of these files are on the same server (either localhost or web server), it works and `alert(&quot;Success&quot;)` is called; If it is on different servers, meaning testserver.php on web server and test.php on localhost, its not working, and `alert(&quot;Error&quot;)` is executing. Even if the URL inside ajax is changed to http://domain.com/path/to/file/testserver.php


Content Type	Original Author	Original Content on Stackoverflow
Question	David Wolever	View Question on Stackoverflow
Solution 1 - Javascript	Kangur	View Answer on Stackoverflow
Solution 2 - Javascript	Doug Neiner	View Answer on Stackoverflow
Solution 3 - Javascript	chim	View Answer on Stackoverflow

Sending credentials with cross-domain posts?

Javascript Problem Overview

Javascript Solutions

Solution 1 - Javascript

Solution 2 - Javascript

Solution 3 - Javascript

Shortcut key to select word in Eclipse

What is the point of the class Option[T]?

Attributions