AutoFilterStarting プロパティ

// The client event 'AutoFilterStarting' takes two parameters sender and e
// sender  is the object which is raising the event
// e is the DropDownEditEventArgs
function WebDropDown_AutoFilterStarting(sender, e) {
    if (!confirm("Are you sure you want to continue with filtering?"))
        //Cancels the AutoFilterStarting event 
        e.set_cancel(true);
}