winform程序中为无边框窗体手动添加窗体拖动代码

        Point oldMousePoint;//记录开始移动窗口前鼠标点下箭头的位置
        Point oldFormPoint;//记录开始移动窗口前窗体位置
        /// <summary>
        /// 窗体鼠标按下事件中初始化oldMousePoint，oldFormPoint
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Form1_MouseDown(object sender, MouseEventArgs e)
        {
            if(e.Button ==MouseButtons .Left )
            {
                oldMousePoint = new Point(Control.MousePosition.X, Control.MousePosition.Y);
                oldFormPoint = this.Location;
            }
        }

---

        /// 窗体鼠标按下移动事件中分别算出鼠标箭头新的位置与旧位置在X,Y方向上的增量并分别加在原始旧窗口的X,Y方向上
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Form1_MouseMove(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)//判断是否是鼠标左键按下
            {
                int addPointX = Control.MousePosition.X - oldMousePoint.X;
                int addPointY = Control.MousePosition.Y - oldMousePoint.Y;
                this.Location = new Point(oldFormPoint.X + addPointX, oldFormPoint.Y + addPointY);
            }
        }