ASP.NET Treeview Control not expanding on click

Question

I having an issue with the ASP.NET Treeview control. I create the treeview just fine but the nodes will not expand or collapse. I see there is a javascript error but it is for line 1 character 0 of the webpage, there is nothing at line 1 character 0.

I am using the ASP:Treeview control in conjunction with the Telerik controls, but I'm not sure if that is an issue.

I saw there was a similar question here but the answer is not pertinent to my site. Has anyone run into this issue before? I've tried searching Google and tried a number of proposed solutions but so far none have worked.

Thank you,

Answer 1

Normally with problems like this it is best to isolate the code which is causing the problem. For example, create a minimal page with no other controls or external JavaScript and see if the problem persists.

It's also useful to use a decent debugger. The latest IE8 actually has a very good Visual Studio-style JavaScript debugger built in - go to your page, hit F12 and the go to the Script tab and click 'Start Debugging' and see where that leads you.

Answer 2

I've seen unhelpful javascript errors when a page does an AJAX postback, an exception occurs on the server, and the client javascript is unable to handle what the server returns. You could ascertain if this is happening by debugging the site, putting a breakpoint on the Page_Load method (or something similar), and see if it gets hit when trying to collapse or expand the TreeView.