TreeNode Parent( )
Parent node of the child node which calls this method. Returns NULL if the node is root node.
TreeNode tn1, tn2, tn3;
tn2 = myTree.AddTextNode("abc", "node2", 2);
tn3 = tn2.AddTextNode("efg", "node3", 3); //tn3 is added to tn2 as its child
tn1 = tn3.Parent();//now tn1 and tn2 refer to the same node, which is the parent of tn3