System.Windows.Forms.TreeNodeCollection.AddInternal C# (CSharp) Method

        private int AddInternal(TreeNode node, int delta)
        {
            if (node == null)
                throw new ArgumentNullException("node");

            if (node.parent != null) node.Remove();

            node.parent = this.owner;
            node.index = items.Count;

            items.Add(node);

            if (owner.TreeView != null)
            {
                node.treeView = owner.TreeView;
            }

            return node.index;
        }