鼠标拖动窗体功能

        static int cx = 0;
        static int cy = 0;
        static bool move = false;

        private void label1_MouseDown(object sender, MouseEventArgs e)
        {
            cx = e.X;
            cy = e.Y;
            move = true;
        }
        private void label1_MouseMove(object sender, MouseEventArgs e)
        {
            if (move)
            {

                this.Left += e.X - cx;
                this.Top += e.Y - cy;
            }
        }

        private void label1_MouseUp(object sender, MouseEventArgs e)
        {
            move = false;
        }