程序代码：

Option Explicit
Dim xa(-360 To 360) As Double
Dim ya(-360 To 360) As Double
Const PI = 3.14159
Public Sub zuobiao()
Dim L1 As Integer
L1 = Val(Text1.Text)
Dim k1 As Integer
For k1 = 0 To 360
xa(k1) = L1 * Cos(k1 * PI / 180)
ya(k1) = L1 * Sin(k1 * PI / 180)
Next k1
End Sub
Private Sub Command1_Click()
Timer1.Enabled = True
Picture1.Cls
End Sub

Private Sub Form_Load()
Picture1.Scale (-80, 80)-(80, -80)
Picture1.Circle (0, 0), 10, RGB(0, 0, 0)
Picture1.Circle (20, 0), 10, RGB(255, 0, 0)
Picture1.Line (0, 0)-(20, 0), RGB(0, 0, 0)
End Sub

Private Sub Timer1_Timer()
Call zuobiao
Dim k2 As Integer
Picture1.Circle (0, 0), 10, RGB(0, 0, 0)
Picture1.Circle (xa(k2), ya(k2)), 10, RGB(255, 0, 0)
Picture1.Line (0, 0)-(xa(k2), ya(k2)), RGB(0, 0, 0)
End Sub