vb424实时错误，怎么改？

Private Sub Command1_Click()
Dim circleobj As AcadCircle
Dim centerpoint(0 To 2) As Double
Dim radius As Double
centerpoint(0) = 20#: centerpoint(1) = 30#: centerpoint(2) = 0#
radius = 5#

显示黄色行
Set circleobj = acadapp.ActiveDocument.ModelSpace.AddCircle(centerpoint, radius)

ZoomAll
End Sub

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