How do I test if optional arguments are supplied or not?

Question

How do I test if optional arguments are supplied or not? -- in VB6 / VBA

Function func (Optional ByRef arg As Variant = Nothing)

    If arg Is Nothing Then          


        

Answer 1

You can use something like:

function func(optional vNum as integer:=&HFFFF) '&HFFFF value that is NEVER set on vNum

If vNum = &HFFFF Then
    MsgBox "NOT SENT"
End If

End Function