Hi,
In the case of collasping other two panels I would suggest you to use Accordion control instead of CollapsiblePanelExtender. If you want to stick with same control. try all the properties of that control like AutoExpand and AutoCollapse etc.
In the case to clear text boxes as in this case page does not postback with ajaxcontrols so maintain Viewstate of the controls that you want to clear.
for more ajax help visit.
http:// ajaxcontroltoolkit.com
Thanks
Mahesh
I have 3 collapsible panel extenders containing other controls on my web page. Initially, I am loading one on page load. I want to collapse other 2 panels on click of any one out of those three as well as want to make the textboxes blank contained by them. Can you suggest me how will it work?
thks