ASP.NET and AJAX
In this tutorial, we’ll take a look at some of the things you can do with ASP.NET and AJAX in your web applications. It’s more than just wrapping an UpdatePanel around some buttons, textboxes and grids!
Though this tutorial will focus primarily on other components besides the UpdatePanel, it might be useful to take a look at postback triggers as well. Wrapping some controls on a webform in an UpdatePanel is a cheap and cheerful way of implementing Ajax.
Postbacks caused by the web controls in the UpdatePanel should happen asynchronously and not cause an entire page postback. There are, however, many caveats with arbitrarily dropping UpdatePanels onto webforms and hoping for the best.
There are also situations in which one may want to conditionally cause a postback of the entire page, or perhaps just make one method call to a backend method or web service to update some small part of the page.
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