Hi,
Add a BehaviorID to the CollapsiblePanelExtender .
BehaviorId="collapsibleBehavior"
Use JS Functions to hook onto the Expand and collapse events.
EX:
function pageLoad(sender,args){
$find("collapsibleBehavior").add_expandComplete( expandHandler );
$find("collapsibleBehavior").add_add_collapseComplete( collapseHandler );
}
function expandHandler( sender , args ){
alert('I have expanded');
}
function collapseHandler( sender , args ){
alert('I have collapsed');
}
Hope this helps.
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