// Draw the Line that is cross private void DrawReversibleLine(Point p) { ControlPaint.DrawReversibleLine( PB_FS.PointToScreen(new Point(0, p.Y)), PB_FS.PointToScreen(new Point(PB_FS.Width, p.Y)), Color.Red); ControlPaint.DrawReversibleLine( PB_FS.PointToScreen(new Point(p.X, 0)), PB_FS.PointToScreen(new Point(p.X, PB_FS.Height)), Color.Red); }