Hello Christopher,

My experience with the Treeview would say that you need to manage the state
of the nodes yourself and that Treeview.FindNode() is your friend:

// Function to collapse all the nodes of a treeview control but the given
parameter

protected void ExpandNode(string expandThisNode)
{
       foreach (TreeNode tn in myTreevie.Nodes)
       {
           tn.Collapse();
       }
       TreeNode tnExpandThisNode = tvPhoto.FindNode((string)expandThisNode);
       tnExpandThisNode.Expand();
}