如下的程序绘制多边形，请将程序填写完整private void button1_Click(object sender, EventArgs e){Graphics g = 第1空Pen myPen = new Pen(Color.Black, 4);Point point1 = new Point(0, 0);Point point2 = new Point(0, 100);Point point3 = new Point(100, 0);Point[] Points = { point1, point2, point3 };第2空}