treeview右键添加新节点

     private void advTree1_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Right)//判断你点的是不是右键
            {
                Point ClickPoint = new Point(e.X, e.Y);
                Node CurrentNode =advTree1.GetNodeAt(ClickPoint);
                if (CurrentNode != null)//判断你点的是不是一个节点
                {
                    ContextMenu menu = new System.Windows.Forms.ContextMenu(); 

                    MenuItem i = new MenuItem();
                    i.Text = "llllll";
                    menu.MenuItems.Add(i);
                    CurrentNode.ContextMenu = menu;

                    advTree1.SelectedNode = CurrentNode;//选中这个节点
                }
            }
        }