node.ExpandChildNodes() means that the childs of "node" should be expanded, in your case it's the node with text "dummy", but it has no childs, so there's no result. You can expand a node like this:
|RadTreeView1.Nodes.Expanded = true;
but this will not fire OnNodeExpand event, because it's fired only by user interaction (mouse click) or by calling the expand() client-side method.
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