球操作 picture里面如何画图

球操作 picture里面怎么画图
我只需要画圆和直线就够了 请教怎么画

[解决办法]

C# code

        private void Form1_Paint(object sender, PaintEventArgs e)        {            e.Graphics.DrawEllipse(Pens.Red, new Rectangle(0, 0, 100, 100));            e.Graphics.DrawLine(Pens.Red, new Point(0, 0), new Point(100, 100));        }
[解决办法]
在picture的Paint事件中写一楼的代码。完整的如下:
  private void picture1_Paint(object sender, PaintEventArgs e)
       {
           e.Graphics.DrawEllipse(Pens.Red, new Rectangle(0, 0, 100, 100));
           e.Graphics.DrawLine(Pens.Red, new Point(0, 0), new Point(100, 100));
       }