jQuery Forum

Delegate is used to attach the event handler to a parent element (i.e. the "delegate").

So say you have

1. <div id="container">
2.       <span id="myid">test</span>
3. </div>

then your delegate event handler would be

1. $('#container').delegate('#myid', 'click', function() {
2.       //do something
3. });

This is essentially the same as

1. $('#myid', $('#container')[0]).live('click', function() {
2.       //do something
3. });

If you use .live() it always attachs the event handler to the Document level.

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ok thanks! so you must always use the nearest parent element?

The only disadvantage are then:

- if you change your html this could be broken
- it dont work on classes:

 <div id="container">
         <span class="myid">test</span>
</div>

<span class="myid">another test</span>

this doesn't work..often you use a class for an jquery action but in the html it could be on a different place

so delegate is not perfect

You don't have to bind the handler to the nearest parent, you could bind it to the document, html, body, or any ancestors.

Delegate & Live are virtually identical, delegate just provides a more logical manner of assigning the handler TO the delegate.

Also, by assigning it to a specific delegate rather than to the document (by default with .live()), you are able to reach the handler quicker when the event bubbles from the target through the DOM tree.