C#?TreeviewNode的拖动，Node节点上下移动

      定义一个TreeView 名字为TVdepartment,设置allowdrop为True //移动代码

        private void MiMoveUp_Click(object sender, EventArgs e) //向上移动
        ...{
            //by 闫磊 Email:[e-mail],[e-mail] 2007.10.10
            TreeNode Node = TVdepartment.SelectedNode;
            TreeNode PrevNode = Node.PrevNode;
            if (PrevNode != null)
            ...{

                TreeNode NewNode = (TreeNode)Node.Clone();
                if (Node.Parent == null)
                ...{
                    TVdepartment.Nodes.Insert(PrevNode.Index, NewNode);
                }
                else
                ...{
                    Node.Parent.Nodes.Insert(PrevNode.Index, NewNode);
                }
                Node.Remove();
                TVdepartment.SelectedNode = NewNode;

            }

        }
        private void MiMoveDown_Click(object sender, EventArgs e)//向下移动
        ...{
            //by 闫磊 Email:[e-mail],[e-mail] 2007.10.10
            TreeNode Node = TVdepartment.SelectedNode;
            TreeNode NextNode = Node.NextNode;
            if (NextNode != null)
            ...{

                TreeNode NewNode = (TreeNode)Node.Clone();
                if (Node.Parent == null)
                ...{
                    TVdepartment.Nodes.Insert(NextNode.Index + 1, NewNode);
                }
                else
                ...{
                    Node.Parent.Nodes.Insert(NextNode.Index + 1, NewNode);
                }
                Node.Remove();
                TVdepartment.SelectedNode = NewNode;

            }
        }
        //拖动代码
        private void TVdepartment_ItemDrag(object sender, ItemDragEventArgs e)//左键拖动
        ...{
            if (e.Button == MouseButtons.Left)
            ...{
                DoDragDrop(e.Item, DragDropEffects.Move);
            }

        }

        private void TVdepartment_DragEnter(object sender, DragEventArgs e)
        ...{
            if (e.Data.GetDataPresent("System.Windows.Forms.TreeNode"))
            ...{
                e.Effect = DragDropEffects.Move;
            }
            else
            ...{
                e.Effect = DragDropEffects.None;
            }

        }

        private void TVdepartment_DragDrop(object sender, DragEventArgs e)//拖动
        ...{
            //by 闫磊 Email:[e-mail],[e-mail] 2007.10.10
            //获得拖放中的节点
            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.TVdepartment.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 == 0)
            ...{
                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
            TVdepartment.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();

        }