VbScript validate IBAN with mod97 (number is too big)
So I am writing an application in VbScript and I am trying to validate an IBAN number. The problem though, the number I have to mod with, is too big.
For example: 734027177486111478 mod 97
that is what I want to do, but I can't seem to find a type to use for doing this. Underneath is the code I am using at the moment. In the case of the example, vCheckCode at the last point is 734027177486111478.
Function checkIBAN(ByVal vIban)
vLandcode = Mid(vIban, 1, 2)
Select Case vLandcode
Case "BE"
vIban = Replace(vIban, " ", "")
If Len(vIban) = 16 Then
vPrefix = Mid(vIban, 1, 4)
vCheckCode = Replace(vIban, vPrefix, "")
vSuffix = Replace(vPrefix, "BE", "1114")
vCheckCode = vCheckCode + vSuffix
vCheckCode = CDbl(vCheckCode)
vResult = vCheckCode Mod 97
End If
End Select
End Function
Any idea on how to do this?
Thanks in advance!
Answer
In case you need the function to be a bit broader (inspired by Schnouki):
Public Function VALIDATEIBAN(ByVal IBAN As String) As String
' Created by : Koen Rijnsent (www.castoro.nl)
' Inspired by : Chris Fannin (AbbydonKrafts)
' Inspired by : bonsvr (http://stackoverflow.com/users/872583/bonsvr)
' Inspired by : schnouki http://stackoverflow.com/users/113325/schnouki
On Error GoTo CatchError
Dim objRegExp As Object
Dim IBANformat As Boolean
Dim IBANNR As String
Dim ReplaceChr As String
Dim ReplaceBy As String
Dim LeftOver As Long
Dim digit As Integer
Dim i As Long
'Base format clean - uppercase and remove spaces
IBAN = Replace(UCase(IBAN), " ", "")
'Check format, length 15-31 characters, first countrycode, then two digits, then number
Set objRegExp = CreateObject("vbscript.regexp")
objRegExp.IgnoreCase = True
objRegExp.Global = True
objRegExp.Pattern = "[a-zA-Z]{2}[0-9]{2}[a-zA-Z0-9]{11}([a-zA-Z0-9]?){0,16}"
IBANformat = objRegExp.Test(IBAN)
'Validity of country code will not be checked!
If IBANformat = False Then
VALIDATEIBAN = "FORMAT NOT RECOGNIZED"
Else
'Flip first 4 characters to the back
IBANNR = Right(IBAN, Len(IBAN) - 4) & Left(IBAN, 4)
'Replace letters by the right numbers
For i = 10 To 35
ReplaceChr = Chr(i + 55)
ReplaceBy = Trim(str(i))
IBANNR = Replace(IBANNR, ReplaceChr, ReplaceBy)
Next i
'Loop through the IBAN, as it is too long to calculate at one go
LeftOver = 0
For i = 1 To Len(IBANNR)
digit = CInt(Mid(IBANNR, i, 1))
LeftOver = (10 * LeftOver + digit) Mod 97
Next
If LeftOver = 1 Then
If Len(IBAN) = IBANLEN(Left(IBAN, 2)) Then
VALIDATEIBAN = "IBAN OK"
ElseIf IBANLEN(Left(IBAN, 2)) = 0 Then
VALIDATEIBAN = "COUNTRYCODE UNKNOWN, 97 CHECK OK"
Else
VALIDATEIBAN = "LENGTH INVALID WITH COUNTRYCODE"
End If
Else
VALIDATEIBAN = "97 CHECK FAILED"
End If
End If
Exit Function
CatchError:
VALIDATEIBAN = "ERROR: " & Err.Description
MsgBox "Module: MODULE - VALIDATEIBAN function" & vbCrLf & vbCrLf _
& "Error#: " & Err.Number & vbCrLf & vbCrLf & Err.Description
End Function
And a function for the countrycode/length:
Function IBANLEN(CountryCode As String) As Integer
' Created by : Koen Rijnsent (www.castoro.nl)
If Len(CountryCode) <> 2 Then
IBANLEN = 0
Else
'List of country codes, based on http://en.wikipedia.org/wiki/International_Bank_Account_Number
Select Case CountryCode
Case "AL": IBANLEN = 28
Case "AD": IBANLEN = 24
Case "AE": IBANLEN = 23
Case "AO": IBANLEN = 25
Case "AT": IBANLEN = 20
Case "AZ": IBANLEN = 28
Case "BH": IBANLEN = 22
Case "BE": IBANLEN = 16
Case "BA": IBANLEN = 20
Case "BF": IBANLEN = 27
Case "BI": IBANLEN = 16
Case "BJ": IBANLEN = 28
Case "BR": IBANLEN = 29
Case "BG": IBANLEN = 22
Case "CH": IBANLEN = 21
Case "CI": IBANLEN = 28
Case "CM": IBANLEN = 27
Case "CR": IBANLEN = 21
Case "CV": IBANLEN = 25
Case "CY": IBANLEN = 28
Case "CZ": IBANLEN = 24
Case "DE": IBANLEN = 22
Case "DK": IBANLEN = 18
Case "DO": IBANLEN = 28
Case "EE": IBANLEN = 20
Case "ES": IBANLEN = 24
Case "FO": IBANLEN = 18
Case "FI": IBANLEN = 18
Case "FR": IBANLEN = 27
Case "GB": IBANLEN = 22
Case "GE": IBANLEN = 22
Case "GI": IBANLEN = 23
Case "GR": IBANLEN = 27
Case "GL": IBANLEN = 18
Case "GT": IBANLEN = 28
Case "HR": IBANLEN = 21
Case "HU": IBANLEN = 28
Case "IE": IBANLEN = 22
Case "IL": IBANLEN = 23
Case "IR": IBANLEN = 26
Case "IS": IBANLEN = 26
Case "IT": IBANLEN = 27
Case "KZ": IBANLEN = 20
Case "KW": IBANLEN = 30
Case "LB": IBANLEN = 28
Case "LI": IBANLEN = 21
Case "LT": IBANLEN = 20
Case "LU": IBANLEN = 20
Case "LV": IBANLEN = 21
Case "MC": IBANLEN = 27
Case "MD": IBANLEN = 24
Case "ME": IBANLEN = 22
Case "MG": IBANLEN = 27
Case "MK": IBANLEN = 19
Case "ML": IBANLEN = 28
Case "MT": IBANLEN = 31
Case "MR": IBANLEN = 27
Case "MU": IBANLEN = 30
Case "MZ": IBANLEN = 25
Case "NL": IBANLEN = 18
Case "NO": IBANLEN = 15
Case "PK": IBANLEN = 24
Case "PS": IBANLEN = 29
Case "PL": IBANLEN = 28
Case "PT": IBANLEN = 25
Case "RO": IBANLEN = 24
Case "RS": IBANLEN = 22
Case "SA": IBANLEN = 24
Case "SE": IBANLEN = 24
Case "SI": IBANLEN = 19
Case "SK": IBANLEN = 24
Case "SM": IBANLEN = 27
Case "SN": IBANLEN = 28
Case "TN": IBANLEN = 24
Case "TR": IBANLEN = 26
Case "UA": IBANLEN = 29
Case "VG": IBANLEN = 24
Case Else: IBANLEN = 0
End Select
End If
End Function