public void ScrollDownEvent(Point point)
{
int x = point.X;
int y = point.Y;
WindowsAPI.ClientToScreen(handle, ref point);
int xScreenPos = point.X;
int yScreenPos = point.Y;
int delta = (120 * -1) << 16;
this.MouseMove(new Point(x, y));
WindowsAPI.PostMessage(handle, WM_MOUSEWHEEL, (IntPtr)delta, paramHelper.createCoordinatesLParam(xScreenPos, yScreenPos));
}