http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspxThis is what we got couple of weeks ago: an Ajax enabled ASP.NET web application was using a TreeView control within an UpdatePanel to show a complex tree of hierarchical data (the sample we got had more than 2.000 nodes with varying degrees of nesting).it-ITCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#8391825Mon, 14 Apr 2008 13:35:23 GMT91d46819-8472-40ad-a661-2c78acb4018c:8391825Microsoft news and tips &raquo; Very slow TreeView in UpdatePanel<p>PingBack from <a rel="nofollow" target="_new" href="http://microsoftnews.askpcdoc.com/?p=2245">http://microsoftnews.askpcdoc.com/?p=2245</a></p> http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#8435022Mon, 28 Apr 2008 13:13:19 GMT91d46819-8472-40ad-a661-2c78acb4018c:8435022Mohammed Mohi<p>Thanks man it is very useful article</p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#8435741Mon, 28 Apr 2008 20:18:36 GMT91d46819-8472-40ad-a661-2c78acb4018c:8435741Eric Tsai<p>Thanks! Setting EnableClientScript to false solves my problem.</p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#8655096Thu, 26 Jun 2008 09:43:01 GMT91d46819-8472-40ad-a661-2c78acb4018c:8655096Mahendra<p>thank you veru much </p> <p>it solved my problem</p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#8926156Fri, 05 Sep 2008 13:22:15 GMT91d46819-8472-40ad-a661-2c78acb4018c:8926156Eric<p>Now another script (<a rel="nofollow" target="_new" href="http://geekswithblogs.net/ranganh/archive/2006/03/25/73300.aspx">http://geekswithblogs.net/ranganh/archive/2006/03/25/73300.aspx</a>) to auto check-uncheck children with it's parent doesn't work for collapsed children.</p> <p>But it speeds up the postback! Very good tip.</p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#9141548Tue, 25 Nov 2008 14:08:35 GMT91d46819-8472-40ad-a661-2c78acb4018c:9141548Stan Velev<p>Actually, if you are using ASP.Net 3.5 (which is the relevant version for the documentation you are quoting), you can have the tree within an UpdatePanel, with the EnableClientScript set to &quot;true&quot;, but have the UpdatePanel property ChildrenAsTriggers set to &quot;false&quot;. Then you have to list all the events that should trigger the postback on the UpdatePanel as AsyncPostBackTriggers, and hopefully your TreeView TreeNodeCollapsed and TreeNodeExpanded would not be among these. This way, the tree will use its own AJAX to draw itself on expand/collapse, while any other events which need to trigger an UpdatePanel refresh, will do so. </p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#9184643Mon, 08 Dec 2008 16:48:46 GMT91d46819-8472-40ad-a661-2c78acb4018c:9184643Geoff<p>Thank you! This helped solve the problem I was having (ajax collapsing everything upon TreeNodeExpanded)</p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#9762947Tue, 16 Jun 2009 22:36:32 GMT91d46819-8472-40ad-a661-2c78acb4018c:9762947Justin<p>Very useful article. It fixed my problem where Treeview within an UpdatePanel throws javascript error upon expanding/collapsing nodes.</p>http://blogs.msdn.com/carloc/archive/2008/04/14/very-slow-treeview-in-updatepanel.aspx#9810877Wed, 01 Jul 2009 15:10:46 GMT91d46819-8472-40ad-a661-2c78acb4018c:9810877Joe O<p>Thank you. &nbsp;This sped up my postbacks greatly!</p>