protected virtual void TrackBarDrawHorizontalThumb (Graphics dc, Rectangle thumb_pos, Brush br_thumb, Rectangle clippingArea, TrackBar trackBar)
{
Pen pen = SystemPens.ControlLightLight;
dc.DrawLine (pen, thumb_pos.X, thumb_pos.Y, thumb_pos.X + 9, thumb_pos.Y);
dc.DrawLine (pen, thumb_pos.X, thumb_pos.Y, thumb_pos.X, thumb_pos.Y + 19);
pen = SystemPens.ControlDark;
dc.DrawLine (pen, thumb_pos.X + 9, thumb_pos.Y + 1, thumb_pos.X + 9, thumb_pos.Y + 19);
dc.DrawLine (pen, thumb_pos.X + 1, thumb_pos.Y + 10, thumb_pos.X + 8, thumb_pos.Y + 19);
pen = SystemPens.ControlDarkDark;
dc.DrawLine (pen, thumb_pos.X + 10, thumb_pos.Y, thumb_pos.X + 10, thumb_pos.Y + 20);
dc.DrawLine (pen, thumb_pos.X, thumb_pos.Y + 20, thumb_pos.X + 9, thumb_pos.Y + 20);
dc.FillRectangle (br_thumb, thumb_pos.X + 1, thumb_pos.Y + 1, 8, 18);
}
#endregion