c# winform listview 拖放排序

源代碼 http://download.csdn.net/detail/songconglai/5190885

建個winform工程 添加 listview 控件       設置 allowDrop 爲true  ，添加DragDrop，DragEnter，DragLeave，DragOver事件

  public Form1()
        {
            InitializeComponent();
            listView1.ListViewItemSorter = new ListViewIndexComparer();
        }

        private void button1_Click(object sender, EventArgs e)
        {

        }
        //啓動拖拽，設置拖拽的數據和效果。
        private void listView1_ItemDrag(object sender, ItemDragEventArgs e)
        {
            listView1.DoDragDrop(e.Item, DragDropEffects.Move);
        }

        //拖拽進入ListView，判斷拖拽的數據格式，並設置拖拽的效果。
        private void listView1_DragEnter(object sender, DragEventArgs e)
        {
            e.Effect = e.AllowedEffect;
            //e.Effect = DragDropEffects.Move;
        }
        //拖動經過ListView時，設置拖動的效果，顯示拖放位置線
        private void listView1_DragOver(object sender, DragEventArgs e)
        {
            Point ptScreen = new Point(e.X, e.Y);
            Point pt = listView1.PointToClient(ptScreen);
            ListViewItem item = listView1.GetItemAt(pt.X, pt.Y);
          
            int targetIndex = listView1.InsertionMark.NearestIndex(pt);
            if (targetIndex >-1)
            {
                Rectangle itemBounds = listView1.GetItemRect(targetIndex);
                if (pt.X > itemBounds.Left + (itemBounds.Width / 2))
                {
                    listView1.InsertionMark.AppearsAfterItem = true;
                }
                else {
                    listView1.InsertionMark.AppearsAfterItem = false;
                }
            }
            listView1.InsertionMark.Index = targetIndex;
            //if (item != null)
            //    item.Checked = true;
        }

        //拖拽釋放，移動行
        private void listView1_DragDrop(object sender, DragEventArgs e)
        {
            int targetIndex = listView1.InsertionMark.Index;
            if (targetIndex == -1)
            {
                return;
            }
            if (listView1.InsertionMark.AppearsAfterItem)
            {
                targetIndex++;
            }
            
            ListViewItem draggedItem = (ListViewItem)e.Data.GetData(typeof(ListViewItem));
            //Point ptScreen = new Point(e.X, e.Y);
            //Point pt = listView1.PointToClient(ptScreen);
            //ListViewItem targetItem = listView1.GetItemAt(pt.X, pt.Y);//拖動的項將放置於該項之前
            
            //if (null == targetItem || targetItem == draggedItem)
            //    return;

            // NeedForFix: 項實際已經交換，但是顯示沒有交換
            listView1.BeginUpdate();
          
            listView1.Items.Insert(targetIndex, (ListViewItem)draggedItem.Clone());
            listView1.Items.Remove(draggedItem);
            listView1.EndUpdate();
        }

        private void listView1_DragLeave(object sender, EventArgs e)
        {
            listView1.InsertionMark.Index = -1;
        }
        private class ListViewIndexComparer : System.Collections.IComparer
        {
            public int Compare(object x, object y)
            {
                return ((ListViewItem)x).Index - ((ListViewItem)y).Index;
            }
        }

        private void listView1_SelectedIndexChanged(object sender, EventArgs e)
        {

        }
    }
}