Building Interactive User Interfaces with Microsoft ASP.NET AJAX: Using the UpdatePanel

In Part 1 of this article series we looked at the basics of the ASP.NET AJAX framework. We discussed how to download and install the framework and the basics of the UpdatePanel. The UpdatePanel makes creating interactive user interfaces as easy as dragging and dropping. Simply add an UpdatePanel to the page and, within it, add those controls that you want to participate in the partial postback. With the UpdatePanel in place, any postback caused by a control within the UpdatePanel is converted into a partial page postback. Like with a full page postback, a partial page postback sends a request back to the server but does so through client-side script. Moreover, only those regions within UpdatePanels are rended and have their markup return in the HTTP response, and that markup is updated through JavaScript. In short, partial page postbacks make the page seem "snappier." There's less data sent between the client and server and the page is fluidly updated - there's no "flash" as with typical postbacks.

The UpdatePanel in Part 1 was pretty simplistic, involving a Label and a Button control. In this tutorial we'll look at some more real-world uses of the UpdatePanel and, in doing so, we will explore the UpdatePanel's properties in greater depth. In particular, this article first looks at using the GridView within the UpdatePanel. Next, it explores a demo that includes multiple UpdatePanels on the page and illustrates the effect of the UpdatePanel's UpdateMode, ChildrenAsTrigger, and Triggers properties. Read on to learn more!

Source Click Here.