On Error Resume Next
Dim objRef1,objRef2
Set objRef1 = GetRef("DoStuff1")
If objRef1 Is Nothing Then
    Call objRef1
Else
    MsgBox "DoStuff1 is not defined!"
End If
 
Set objRef2 = GetRef("DoStuff2")
If objRef2 Is Nothing Then
    MsgBox "DoStuff2 is not defined!"
Else
    Call objRef2
End If
 
Sub DoStuff1
    MsgBox "DoStuff1!"
End Sub

如果您尝试获取指针的子或函数不存在(如DoStuff2的情况),则GetRef的调用将生成异常.然后,您可以检查引用是否按预期设置.