This AJAX enabled control shows a tree of data. The only thing that you need to implement is a WebService that is called for retrieving the sub nodes of a given node.
The AJAX control is using a webservice for retrieving the list of sub-nodes (folders and files) from a given node (the user clicks):
public XmlNode GetSubNodes(string path)
On the web page a AJAX enabled web control is included:
<ajax:TreeView id="TreeView2" runat="server" service="proxies.TreeView.GetSubNodes" title="Cities in the USA" />
You can find a more detailed documentation in the accompanying book at: http://www.mathertel.de/Ajax/AJAXeBook.aspx
This page is part of the http://www.mathertel.de/AJAXEngine/ project. For updates and discussions see The AJAX Engine blog.