为DataGridView增加鼠标滚轮功能

#region 鼠标滚动

        [System.Runtime.InteropServices.DllImport("user32.dll", EntryPoint = "WindowFromPoint")]

        static extern IntPtr WindowFromPoint(Point pt);

        private void dgv_MouseEnter(object sender, EventArgs e)

        {

            this.MouseWheel += dgv_MouseWheel;

        }

        public void dgv_MouseWheel(object sender, MouseEventArgs e)

        {

            Point p = PointToScreen(e.Location);

            if ((WindowFromPoint(p)) == dgv.Handle)//鼠标指针在框内

            {

                if (e.Delta > 0)

                {

                    if (dgv.FirstDisplayedScrollingRowIndex - 5 < 0)

                    {

                        dgv.FirstDisplayedScrollingRowIndex = 0;

                    }

                    else

                    {

                        dgv.FirstDisplayedScrollingRowIndex = dgv.FirstDisplayedScrollingRowIndex - 5;

                    }

                }

                else

                {

                    dgv.FirstDisplayedScrollingRowIndex = dgv.FirstDisplayedScrollingRowIndex + 5;

                }

            }

        }

        #endregion