How event listener work in java script..

How event listener work in java script.....kindly tell me its functionality..........

 

What API? Do you use jQuery, Prototype, Mootools... ?

You can see basics here

 

I am using prototype..........

 

Good choice

If you need mouse events you can use like this:

$('some_id').observe('mouseover',function() {
// your code here
});

Code (markup):

or like this

Event.observe($('some_id'),'mouseup',function(){
//code...
});

Code (markup):