IsMissing Function

Syntax              IsMissing(expr)

Group                Variable Info

Description       Return the True if Optional parameter expr does not have a defaultvalue and it did not get a value. An Optional parameter may be omitted in the Sub, Function or Property call.

Example            '#Language "WWB-COM"
Sub Main
    Opt              'IsMissing(A)=True
    Opt "Hi"         'IsMissing(A)=False
    Many             'No args
    Many 1,"Hello"   'A(0)=1 A(1)=Hello
    OptBye           '"Bye"
    OptBye "No"      '"No"
End Sub

Sub Opt(Optional A)
    Debug.Print "IsMissing(A)="; IsMissing(A)
End Sub

Sub Many(ParamArray A())
    If LBound(A) > UBound(A) Then
        Debug.Print "No args"
    Else
        For I = LBound(A) To UBound(A)
            Debug.Print "A(" & I & ")=" & A(I) & " ";
        Next I
        Debug.Print
    EndIf
End Sub

Sub OptBye(Optional A As String = "Bye")
    Debug.Print A
End Sub