TreeView 節點拖拽

 1 public Form1()
 2 {
 3  InitializeComponent();
 4  treeView1.AllowDrop = true;
 5  treeView1.ItemDrag += new ItemDragEventHandler(treeView1_ItemDrag);
 6  treeView1.DragEnter += new DragEventHandler(treeView1_DragEnter);
 7  treeView1.DragDrop += new DragEventHandler(treeView1_DragDrop);
 8 }
 9 void treeView1_DragDrop(object sender, DragEventArgs e)
10 {
11  TreeNode moveNode = (TreeNode)e.Data.GetData("System.Windows.Forms.TreeNode");
12  //根據滑鼠坐標確定要移動到的目標節點
13  Point pt;
14  TreeNode targeNode;
15  pt = ((TreeView)(sender)).PointToClient(new Point(e.X, e.Y));
16  targeNode = this.treeView1.GetNodeAt(pt);
17  //如果目標節點無子節點則添加為同級節點,反之添加到下級節點的未端
18  TreeNode NewMoveNode = (TreeNode)moveNode.Clone();
19  if (targeNode.Nodes.Count == 0)
20  {
21   targeNode.Parent.Nodes.Insert(targeNode.Index, NewMoveNode);
22  }
23  else
24  {
25   targeNode.Nodes.Insert(targeNode.Nodes.Count, NewMoveNode);
26  }
27  //更新當前拖動的節點選擇
28  treeView1.SelectedNode = NewMoveNode;
29  //展開目標節點,便於顯示拖放效果
30  targeNode.Expand();
31  //移除拖放的節點
32  moveNode.Remove();
33 }
34 void treeView1_DragEnter(object sender, DragEventArgs e)
35 {
36  if (e.Data.GetDataPresent("System.Windows.Forms.TreeNode"))
37  {
38   e.Effect = DragDropEffects.Move;
39  }
40  else
41  {
42   e.Effect = DragDropEffects.None;
43  }
44 }
45 void treeView1_ItemDrag(object sender, ItemDragEventArgs e)
46 {
47  if (e.Button == MouseButtons.Left)
48  {
49   DoDragDrop(e.Item, DragDropEffects.Move);
50  }
51 }