This example compares Telerik's ASP.NET DropDownTree control to an embedded TreeView in a ComboBox template demonstrating the effort you will save by using RadDropDownTree.
The integration between the TreeView and ComboBox shows how to set the Text of the ComboBox upon clicking on a TreeNode. This is achieved via JavaScript.
Note: If you wrap the RadComboBox with an AJAX panel and handle the NodeClick server-side event of the RadTreeView,
there will be a postback instead of an AJAX postback. This is caused by the fact that the drop down holding the
RadTreeView is detached and is located outside of the wrapping AJAX panel, so it misses the AJAX conversion.
You can avoid this limitation by calling comboBox.attachDropDown() right before the RadTreeView postbacks,
e.g. in the NodeClicking client-side event handler of the RadTreeView:
function nodeClicking(sender, args)
{
...
comboBox.hideDropDown();
comboBox.attachDropDown();
}