Sys.WebForms.PageRequestManager.getInstance().add_beginRequest(beginrequesthandler);
Sys.WebForms.PageRequestManager.getInstance().add_endRequest(endrequesthandler);
            
function beginrequesthandler(sender, args)
{ExibirAguarde();}

function endrequesthandler(sender, args)
{OcultarAguarde();}