Can ASP.NET AJAX partial rendering work inside a SharePoint 2007 application page?

"You need to have Sharepoint 2007 service pack 1 -- or else there's no chance.
(Sharepoint 2007 predates ajax 1.0 -- they built some support into service pack 1)

Next, from a trouble shooting point of view, test that the exact same code functions as expected when hosted in a regular asp.net page. (Literally copy and paste your code across into a fresh page, to rule out any typographical errors). Ruling sharepoint in or out of the problem area will help narrow down the solution space."

"If you have installed SharePoint 2007 (without Service Pack 1) then you can follow an example like the following article:

AjaxBasePart: Easy ASP.NET 2.0 AJAX Extensions 1.0 and Office SharePoint Server 2007

The reason for this is that there exists a specific problem with mixing doPostback, UpdatePanel and SharePoint -- and the symptom is exactly what you're seeing: a full-page postback instead of an asynchronous postback. See this KB article for a workaround: A Web Part that contains an ASP.NET AJAX 1.0 UpdatePanel control that uses the _doPostBack() ...

Otherwise you can just install Service Pack 1 to fix your problem:

Windows SharePoint Services 3.0 Service Pack 1 (SP1)"

There's a specific problem with mixing doPostback, UpdatePanel and SharePoint -- and the symptom is exactly what you're seeing: a full-page postback instead of an asynchronous postback. See this KB article for a workaround: http://support.microsoft.com/kb/941955

"Todd Bleeker at Mindsharp showed me a piece of code he wrote that can use Ajax on Sharepoint 2.0. It was pretty cool. I believe the company used it on their sharepoint site managment software if you want to take a look. (you used to be able to request a 30 day trial). I bet how to do it is on their yahoo group (I can't remember the name, but I am sure that if you search for mindsharp you'll find it.)

As a note, Ajax has been around for a long time. Microsoft easily supported it since 2002 maybe earlier with the release of IE 5.5 (I don't know about other browsers, I was doing internal development and we only supported ie at the time). It just wasn't called that. The term Ajax is nothing more than a marketing term that someone coined later on."