Private Sub Form_Load()
 
  If zeichenketteEnthalten("fe", "abcdef") = False Then
    MsgBox "nicht enhalten"
  Else
    MsgBox "enthalten"
  End If
 
End Sub
 
Private Function zeichenketteEnthalten(ByVal pSuchenNach As String, ByVal _
  pSuchenIn As String) As Boolean
 
Dim i As Integer
Dim j As Integer
Dim sZeichen As String
Dim bVorhanden() As Boolean
Dim bRetValue As Boolean
 
  ReDim bVorhanden(Len(pSuchenNach))
 
  For i = 1 To Len(pSuchenNach)
    sZeichen = Mid(pSuchenNach, i, 1)
 
    For j = 1 To Len(pSuchenIn)
      If Mid(pSuchenIn, j, 1) = sZeichen Then
        bVorhanden(i) = True
        Exit For
      End If
    Next
  Next
 
  bRetValue = True
  For i = 1 To UBound(bVorhanden)
    If bVorhanden(i) = False Then
      bRetValue = False
      Exit For
    End If
  Next
 
  zeichenketteEnthalten = bRetValue
 
End Function