Public Function GetIndex(ByRef ar() As header, ByVal fName As String) As _
      Integer
        For i As Integer = 0 To ar.Length - 1
            If ar(i).feldname.Trim.ToLower = fName.Trim.ToLower Then
                Return i
            End If
        Next
        ReDim Preserve ar(ar.Length)
        ar(ar.Length - 1) = New header With {.feldname = fName, .feldwert = ""}
        Return ar.Length - 1
    End Function

Those people who think they know everything are a great annoyance to those of us who do - Isaac Asimov