求设计个简单的VB程序

主要代码
Private Sub Command1_Click()
D = InputBox("请输入圆的直径")
S = 3.1415926 / 4 * D ^ 2
L = 3.1415926 * D
MsgBox ("圆的面积" & S & vbCrLf & "圆的周长" & L)
End Sub
Private Sub Command2_Click()
R = InputBox("请输入圆的半径")
S = 3.1415926 * (R ^ 2)
L = 2 * 3.1415926 * R
MsgBox ("圆的面积" & S & vbCrLf & "圆的周长" & L)
End Sub

Private Sub Form_click()
Dim r As Single '定义半径r为单精度(变量)
Const PI As Single = 3.14 '定义PI为单精度(常量)
Dim s As Single '定义面积S为单精度（变量）
r = InputBox("输入r") '半径r通过inputbox函数输入值
s = PI * r ^ 2 '用求圆面积公式，并把值赋给S
Print s '在窗体上打印出S的值
End Sub