I have a javascript function "myFunction()".  I would like this to be called every time the DropDownExtender drops down!  Could someone point me in the right direction about how to do this?

I think that it basically involves the following steps, but I could use a little help with the implementation:

- Give the DropDownExtender a behaviourID
- Grab the DropDownExtender using "$find('BehaviourID');
- Somehow hook myFunction() up to the DropDownExtender!

 
Thanks for any help
 

 OK - so i have figured it out.  For all those who are interested, once you have grabbed the Ajax.Net object using $find(), you can simply subscribe to events using the "add_..." methods.  Just examine which of these are available using a javascript debugger such as firebug.

E.G. If i want to perform an action when the Ajax.Net toolkit drops down, i can simply do the following:

         function pageLoad() {
            var bhvDdl = $find("bhvDdl");
           
            //register
            bhvDdl .add_showing(showing);
        }       

        function showing(){
            alert("showing");
        }

 Si!