Function LastDigitCID(CID)
LastDigitCID = Right(11 - (Mid([CID], 1, 1) * 13 + Mid([CID], 2, 1) * 12 + Mid([CID], 3, 1) * 11 + Mid([CID], 4, 1) * 10 + Mid([CID], 5, 1) * 9 + Mid([CID], 6, 1) * 8 + Mid([CID], 7, 1) * 7 + Mid([CID], 8, 1) * 6 + Mid([CID], 9, 1) * 5 + Mid([CID], 10, 1) * 4 + Mid([CID], 11, 1) * 3 + Mid([CID], 12, 1) * 2) Mod 11, 1)
End Function
Function CIDok(CID) As Boolean
Dim i As Integer, NumDigitCID As Boolean
If IsNull(CID) Then
CIDok = False
ElseIf CID = "" Then
CIDok = False
ElseIf Len(CID) <> 13 Then
CIDok = False
Else
For i = 1 To Len(CID)
If IsNumeric(Mid$(CID, i, 1)) Then
NumDigitCID = True
Else
NumDigitCID = False
Exit For
End If
Next
CIDok = NumDigitCID
End If
If CIDok = True Then
If LastDigitCID(CID) = Right(CID, 1) Then
CIDok = True
Else
CIDok = False
End If
End If
End Function
