Popup window in GridviewControl

Question

Am using a GridView control.In gridview am using Button.when we click a button i want to display the Popup window.Am using the Ajax For popup.Here the Problem is The Targetcontrolid,in this we give the button name which is in the GridView control.But i cant to get the Popup window.

 

 

TargetControlID="lblView" BehaviorID="bhPopup" CancelControlID="btncan" Drag="true" DropShadow="true">