A: 

You can try to enable view state for your tree view control.

Bug  2009-03-05 14:02:05
+1  A: 

I think that depends upon your treeview. The Telerik treeview does this via viewstate...

http://www.telerik.com/community/forums/aspnet/treeview/how-do-i-maintain-treeview-state-after-postback.aspx

... and this following post suggests a way of hand-rolling this...

http://blog.binaryocean.com/PermaLink,guid,23808645-43b5-4e2a-afb1-53dc8da35636.aspx

I've not tried either solution, so can't vouch for them, but they look promising.

Martin Peck  2009-03-05 14:04:00

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