TreeView 节点拖拽

 public Form1()
 {
  InitializeComponent();
  treeView1.AllowDrop = true;
  treeView1.ItemDrag += new ItemDragEventHandler(treeView1_ItemDrag);
  treeView1.DragEnter += new DragEventHandler(treeView1_DragEnter);
  treeView1.DragDrop += new DragEventHandler(treeView1_DragDrop);
 }
 void treeView1_DragDrop(object sender, DragEventArgs e)
 {
  TreeNode moveNode = (TreeNode)e.Data.GetData("System.Windows.Forms.TreeNode");
  //根据鼠标坐标确定要移动到的目标节点
  Point pt;
  TreeNode targeNode;
  pt = ((TreeView)(sender)).PointToClient(new Point(e.X, e.Y));
  targeNode = this.treeView1.GetNodeAt(pt);
  //如果目标节点无子节点则添加为同级节点,反之添加到下级节点的未端
  TreeNode NewMoveNode = (TreeNode)moveNode.Clone();
  if (targeNode.Nodes.Count == )
  {
   targeNode.Parent.Nodes.Insert(targeNode.Index, NewMoveNode);
  }
  else
  {
   targeNode.Nodes.Insert(targeNode.Nodes.Count, NewMoveNode);
  }
  //更新当前拖动的节点选择
  treeView1.SelectedNode = NewMoveNode;
  //展开目标节点,便于显示拖放效果
  targeNode.Expand();
  //移除拖放的节点
  moveNode.Remove();
 }
 void treeView1_DragEnter(object sender, DragEventArgs e)
 {
  if (e.Data.GetDataPresent("System.Windows.Forms.TreeNode"))
  {
   e.Effect = DragDropEffects.Move;
  }
  else
  {
   e.Effect = DragDropEffects.None;
  }
 }
 void treeView1_ItemDrag(object sender, ItemDragEventArgs e)
 {
  if (e.Button == MouseButtons.Left)
  {
   DoDragDrop(e.Item, DragDropEffects.Move);
  }
 }