Admin
08/06/2004, 13:59
Function IsCreditCard(ByVal CreditCardNumber As String) As Boolean
Dim i As Long
Dim j As Long
Dim n As Long
For i = 1 To Len(CreditCardNumber)
j = Val(Mid$(CreditCardNumber, i, 1))
If (Len(CreditCardNumber) And 1) = 0 Then
If i And 1 Then
j = j * 2
If j > 9 Then j = j - 9
End If
Else
If (i And 1) = 0 Then
j = j * 2
If j > 9 Then j = j - 9
End If
End If
n = n + j
Next
IsCreditCard = (n Mod 10) = 0
End Function
Dim i As Long
Dim j As Long
Dim n As Long
For i = 1 To Len(CreditCardNumber)
j = Val(Mid$(CreditCardNumber, i, 1))
If (Len(CreditCardNumber) And 1) = 0 Then
If i And 1 Then
j = j * 2
If j > 9 Then j = j - 9
End If
Else
If (i And 1) = 0 Then
j = j * 2
If j > 9 Then j = j - 9
End If
End If
n = n + j
Next
IsCreditCard = (n Mod 10) = 0
End Function