Ziffern aus Text extrahieren

Public Function GetZiffern(ByVal mywert As String) As String

If Len(mywert) < 1 Or IsNull(mywert) = True Then GetZiffern = "": Exit Function

For i = 1 To Len(mywert)
  x = Mid$(mywert, i, 1)
  If IsNumeric(x) Then
     GetZiffern = GetZiffern & x
  End If
 Next i

End Function