winForm ListView控件内部拖动排序

 

        private void listView1_ItemDrag(object sender, ItemDragEventArgs e)
        {
            listView1.DoDragDrop(listView1.SelectedItems, DragDropEffects.Move);
        }

        private void listView1_DragDrop(object sender, DragEventArgs e)
        {
            //判断是否选择拖放的项，

            if (listView1.SelectedItems.Count == 0)
            {
                return;
            }

            //定义项的坐标点
            Point cp = listView1.PointToClient(new Point(e.X, e.Y));//
            ListViewItem dragToItem = listView1.GetItemAt(cp.X, cp.Y);

            if (dragToItem == null)
            {
                return;
            }

            int dragIndex = dragToItem.Index;
            ListViewItem[] sel = new ListViewItem[listView1.SelectedItems.Count];

            for (int i = 0; i <= listView1.SelectedItems.Count - 1; i++)
            {
                sel = listView1.SelectedItems;
            }

            for (int i = 0; i < sel.GetLength(0); i++)
            {
                ListViewItem dragItem = sel;

                int itemIndex = dragIndex;

                if (itemIndex == dragItem.Index)
                {
                    return;
                }

                if (dragItem.Index < itemIndex)
                    itemIndex++;
                else
                    itemIndex = dragIndex + i;

                ListViewItem insertItem = (ListViewItem)dragItem.Clone();

                listView1.Items.Insert(itemIndex, insertItem);

                listView1.Items.Remove(dragItem);
            }
        }
        private void listView1_DragEnter(object sender, DragEventArgs e)
        {
            for (int i = 0; i <= e.Data.GetFormats().Length - 1; i++)
            {
                if (e.Data.GetFormats().Equals("System.Windows.Forms.ListView+SelectedListViewItemCollection"))
                {
                    e.Effect = DragDropEffects.Move;
                }

            }


        }