private void AddGraphNodeToTree(AcDb.GraphNode graphNode, TreeNode parentTreeNode) { // TBD: for some reason, these are returning GraphNodes, not XrefGraphNodes string name = "*UNNAMED*"; AcDb.XrefGraphNode xNode = graphNode as AcDb.XrefGraphNode; if (xNode != null) name = xNode.Name; TreeNode newTreeNode = new TreeNode(name); newTreeNode.Tag = graphNode; parentTreeNode.Nodes.Add(newTreeNode); for (int i=0; i<graphNode.NumOut; i++) { AddGraphNodeToTree(graphNode.Out(i), newTreeNode); } }