GraphicsPath gp = new GraphicsPath(new Point[]{new Point(0,50),
            new Point(10,50),new Point(20,50),new Point(30,50)},
            new byte[]{(byte)PathPointType.Start,(byte)PathPointType.Line,
            (byte)PathPointType.Line,(byte)PathPointType.Line,
        (byte)PathPointType.});e.Graphics.DrawPath(Pens.Black, gp);
为什么会提示参数无效,该怎么改呢?