UpdatePanel 触发 JS

Sys.WebForms.PageRequestManager.getInstance().add_beginRequest(BeginRequestHandler);

Sys.WebForms.PageRequestManager.getInstance().add_endRequest(EndRequestHandler);  

function BeginRequestHandler(sender, args)   

{          

             var elem = args.get_postBackElement();    

}

function EndRequestHandler(sender, args)     {     }