[求助]在picturebox控件上画函数图像

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim myPen As Graphics = PictureBox1.CreateGraphics
        Dim x1 As Single, y1 As Single, x As Single, y As Single, r As Single, width As Single, height As Single
        r = 1
        For x1 = 1 To 20
            y1 = 6 * x1 - 3
            width = r * 20
            height = r * 20
            x = x1 - width / 1
            y = y1 - height / 1000
            myPen.FillEllipse(Brushes.Red, x, y, width, height)
        Next
        '上面是一个例子，自己琢磨如何绘图吧
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        PictureBox1.Image = Nothing '清除已绘制或加载的图像
    End Sub
End Class