诊治代码错误:总不能痛快地启动CAD的原因

Mrqq18

我在Excel VBA用getobject 或 creatobject 启动CAD(2004),第一次总会出现错误信息,第二次才能正常,为什么?

Dim CAD as object

Private Function OpenCAD() As Boolean
    OpenCAD = True
    On Error Resume Next
    Set CAD = GetObject(, "AutoCAD.Application.16")
    If Err <> 0 Then
        Err.Clear
        Set CAD = CreateObject("AutoCAD.Application.16")    'CAD2004
        If Err <> 0 Then
        '-------
            Err.Clear
            Set CAD = GetObject(, "AutoCAD.Application.16.1")    'CAD2005
            If Err <> 0 Then
                Err.Clear
                Set CAD = CreateObject("AutoCAD.Application.16.1")
                If Err <> 0 Then
                    Err.Clear
                    MsgBox "无法启动CAD...", , "Mrqq"
                    OpenCAD = False
                    Exit Function
                End If
            End If
        '-------
        End If
    End If
End Function

另外,如何在未打开CAD时得到其版本号?

谢谢!