I'd like to get the id of the clicked link with jQuery. Why does this return Undefined instead?    test = function(e) {     alert($(e).attr('id'));     return false; } $('.bleu').click(test) &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"&gt;&lt;/script&gt; &lt;a href="" class="bleu" id="h12"&gt;azeaze12&lt;/a&gt; &lt;a href="" class="bleu" id="h13"&gt;azeaze13&lt;/a&gt; &lt;a href="" class="bleu" id="h14"&gt;azeaze14&lt;/a&gt;
16631
Is there any way to get the ID of the element that fires an event?  I'm thinking something like:    $(document).ready(function() {   $("a").click(function() {     var test = caller.id;     alert(test.val());   }); }); &lt;script type="text/javascript" src="starterkit/jquery.js"&gt;&lt;/script&gt;  &lt;form class="item" id="aaa"&gt;   &lt;input class="title"&gt;&lt;/input&gt; &lt;/form&gt; &lt;form class="item" id="bbb"&gt;   &lt;input class="title"&gt;&lt;/input&gt; &lt;/form&gt;     Except of course that the var test should contain the id "aaa", if the event is fired from the first form, and "bbb", if the event is fired from the second form.
78588
How do you tell if a function in JavaScript is defined?  I want to do something like this  function something_cool(text, callback) {     alert(text);     if( callback != null ) callback(); }   But it gets me a     callback is not a function   error when callback is not defined.
13003
I'm having some trouble with plain old JavaScript (no frameworks) in referencing my object in a callback function.  function foo(id) {     this.dom = document.getElementById(id);     this.bar = 5;     var self = this;     this.dom.addEventListener("click", self.onclick, false); }  foo.prototype = {     onclick : function() {         this.bar = 7;     } };   Now when I create a new object (after the DOM has loaded, with a span#test)  var x = new foo('test');   The 'this' inside the onclick function points to the span#test and not the foo object.  How do I get a reference to my foo object inside the onclick function?
92658
I'm using Jquery's toggle event to do some stuff when a user clicks a checkbox, like this:  $('input#myId').toggle( function(){ //do stuff   }, function(){ //do other stuff     } );   The problem is that the checkbox isn't being ticked when I click on the checkbox. (All the stuff I've put into the toggle event is working properly.)  I've tried the following:  $('input#myId').attr('checked', 'checked');   and  $(this).attr('checked', 'checked');   and even simply  return true;   But nothing is working. Can anyone tell me where I'm going wrong?  Edit - thanks to all who replied. Dreas' answer very nearly worked for me, except for the part that checked the attribute. This works perfectly (although it's a bit hacky)  $('input#myInput').change(function () {     if(!$(this).hasClass("checked"))     {         //do stuff if the checkbox isn't checked         $(this).addClass("checked");         return;     }      //do stuff if the checkbox isn't checked     $(this).removeClass('checked'); });   Thanks again to all who replied.
29285
What's the difference between &lt;div class=""&gt; and &lt;div id=""&gt; when it comes to CSS? Is it alright to use &lt;div id=""&gt;?  I see different developers doing this in both ways, and since I'm self taught, I've never really figured it out.
119086
How to access the Id from URL in visualforce, i want to pass that Id to javascript function to load my page, please help.
22621
I have done the following code in JavaScript to put focus on the particular element (branch1 is a  element),  document.location.href="#branch1";   But as I am also using jQuery in my web app, so I want to do the above code in jQuery. I have tried but don't know why its not working,  $("#branch1").focus();   The above jquery (focus()) code is not working for div, whereas If i am trying the same code with textbox, then its working,  Please tell me, how can I put focus on a div elemnt using jQuery?  Thanks!
36235
I am after documentation on using wildcard or regular expressions (not sure on the exact terminology) with a jQuery selector.  I have looked for this myself but have been unable to find information on the syntax and how to use it. Does anyone know where the documentation for the syntax is?  EDIT: The attribute filters allow you to select based on patterns of an attribute value.
56223
Any idea why the piece of code below does not add the script element to the DOM?  var code = "&lt;script&gt;&lt;/script&gt;"; $("#someElement").append(code);
76641
I need to get item from list sharepoint by Id I use this code and it give me all the items of the list :  &lt;script&gt;  function parseURLParams(url) {         var queryStart = url.indexOf("?") + 1,             queryEnd = url.indexOf("#") + 1 || url.length + 1,             query = url.slice(queryStart, queryEnd - 1),             pairs = query.replace(/\+/g, " ").split("&amp;"),             parms = {}, i, n, v, nv;          if (query === url || query === "") {             return;         }          for (i = 0; i &lt; pairs.length; i++) {             nv = pairs[i].split("=");             n = decodeURIComponent(nv[0]);             v = decodeURIComponent(nv[1]);              if (!parms.hasOwnProperty(n)) {                 parms[n] = [];             }              parms[n].push(nv.length === 2 ? v : null);         }         return parms;     }  $( window ).load(function() {   var urlString = document.URL;  urlParams = parseURLParams(urlString);  ExecuteOrDelayUntilScriptLoaded(retrieveActualite, "sp.js");          var siteUrl = '/sites/securite';      function retrieveActualite() {              var clientContext = new SP.ClientContext(siteUrl);             var oList = clientContext.get_web().get_lists().getByTitle('Actualite');             var camlQuery = new SP.CamlQuery();              camlQuery.set_viewXml('&lt;Query&gt;&lt;Where&gt;&lt;Eq&gt;&lt;FieldRef Name=”ID” LookupId="TRUE"/&gt;&lt;Value Type="Text"&gt;' + urlParams.IdArt[0] + '&lt;/Value&gt;&lt;/Eq&gt;&lt;/Where&gt;&lt;/Query&gt;');             this.collListItem = oList.getItems(camlQuery);             clientContext.load(collListItem);             clientContext.executeQueryAsync(onQuerySucceededActualite, onQueryFailed);         }          function onQuerySucceededActualite(sender, args) {              var listItemInfo = '';              var listItemEnumerator = collListItem.getEnumerator();             while (listItemEnumerator.moveNext()) {                 var oListItem = listItemEnumerator.get_current();                   var desc=oListItem.get_item('Description');                 $('#idArticle').append('&lt;label class="titleArticle"&gt;'+oListItem.get_item('Title')+'&lt;/label&gt; &lt;br&gt;&lt;br&gt;&lt;p class="ContenuArticle" &gt;'+desc+'&lt;/p&gt;');                          }         }          function onQueryFailed(sender, args) {              alert('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());         }       });    &lt;/script&gt;   so how can I get only the considered item ?
42682
I'm using jQuery and I want to check the existence of an element in my page. I have written following code, but it's not working:  if($("#btext" + i) != null) {     //alert($("#btext" + i).text());     $("#btext" + i).text("Branch " + i); }   How do I check the existence of the element?
122496
Is there a way to find JavaScript variable on the page (get it as an object) by its name? Variable name is available as a string constant.
9151
How can I check the existence of an element in jQuery?  The current code that I have is this:  if ($(selector).length &gt; 0) {     // Do something }   Is there a more elegant way to approach this? Perhaps a plugin or a function?
10911
With jQuery, how do I find out which key was pressed when I bind to the keypress event?  $('#searchbox input').bind('keypress', function(e) {});   I want to trigger a submit when ENTER is pressed.  [Update]  Even though I found the (or better: one) answer myself, there seems to be some room for variation ;)  Is there a difference between keyCode and which - especially if I'm just looking for ENTER, which will never be a unicode key?  Do some browsers provide one property and others provide the other one?
17578
In Mootools, I'd just run if ($('target')) { ... }.  Does if ($('#target')) { ... } in jQuery work the same way?
72166
I have some HTML and jQuery that slides a div up and down to show or hide` it when a link is clicked:  &lt;ul class="product-info"&gt;   &lt;li&gt;     &lt;a href="#"&gt;YOU CLICK THIS TO SHOW/HIDE&lt;/a&gt;     &lt;div class="toggle"&gt;       &lt;p&gt;CONTENT TO SHOW/HIDE&lt;/p&gt;     &lt;/div&gt;   &lt;/li&gt; &lt;/ul&gt;   $('div.toggle').hide(); $('ul.product-info li a').click(function(event){   $(this).next('div').slideToggle(200); }   My question is: How do I use preventDefault() to stop the link acting as a link and adding "#" to the end of my URL &amp; jumping to the top of the page?  I can't figure out the right syntax, I just keep getting an error saying      preventDefault() is not a function.
123115
What's the best way to get a regular anchor (&lt;a href="..."&gt;) to submit the form it is embedded in when clicked?  &lt;form&gt;     &lt;ul&gt;         &lt;li&gt;             &lt;p&gt;                 The link could be &lt;span&gt;embedded &lt;a href="" onclick="?"&gt;at any level&lt;/a&gt;&lt;/span&gt;                 in the form, so "this.parentNode.parentNode..." is no good. :(             &lt;/p&gt;         &lt;/li&gt;     &lt;/ul&gt; &lt;/form&gt;   I know that the easiest way using jQuery would be  $('#myLink').click(function() {     $(this).parents('form:first').submit(); });   ...but I'm trying to find a way to do this without using a library.    Edit: I'm really trying to find a method which doesn't require knowledge of the form (eg: its name, id, etc). This would be similar to how you could put this on an input element: &lt;input onclick="this.form.submit()" /&gt;