Have been using AJAX for a while now, and the “UpdatePanel” is great, for a partial page refresh. But – will be good to have some indication to the user that it’s happening – not just a “blank stare” – at a page that is actually doing something, but doesn’t look like it is.
One of the cool new controls provided with the ASP.NET AJAX Extensions (aka “Atlas”) is the UpdateProgress control.
This control allows you to automatically cause UI to display on a page while an AJAX callback is in progress.
Here’s a few examples :
Full Story (Scott Guthrie)