> The code below will pass a credit card as being valid if it contains
> dashes, spaces, and also alphanumerics. How can I check for only
> dashes and spaces and return invalid when the user inputs
> alphanumerics? Thanks.
>
> Sub ValidateCCNumber( s As Object, e As ServerValidateEventArgs )
> Dim intCounter As Integer
> Dim strCCNumber As String
> Dim blnIsEven As Boolean = False
> Dim strDigits As String = ""
> Dim intCheckSum As Integer = 0
> 'Strip away everything except numerals
> FOR intCounter = 1 To Len( e.Value )
> IF IsNumeric( MID( e.Value, intCounter, 1 ) ) THEN
> strCCNumber = strCCNumber & MID( e.Value, intCounter, 1 )
> END IF
> NEXT
> 'IF nothing left, then fail
> IF Len( strCCNumber ) = 0 THEN
> e.IsValid = False
> ELSE
> 'Double every other digit
> FOR intCounter = Len( strCCNumber ) To 1 Step -1
> IF blnIsEven THEN
> strDigits = strDigits & cINT( MID( strCCNumber, intCounter, 1 )
> ) * 2
> ELSE
> strDigits = strDigits & cINT( MID( strCCNumber, intCounter, 1 )
> )
> END IF
> blnIsEven = ( NOT blnIsEven )
> NEXT
> 'Calculate CheckSum
> FOR intCounter = 1 To Len( strDigits )
> intCheckSum = intCheckSum + cINT( MID( strDigits, intCounter, 1
> ) )
> NEXT
> 'Assign results
> e.IsValid = (( intCheckSum Mod 10 ) = 0 )
> END IF
> END Sub

"Sparky Arbuckle" <twa@secureroot.com> wrote in message
news:1112854214.977828.125600@l41g2000cwc.googlegroups.com...
> The code below will pass a credit card as being valid if it contains
> dashes, spaces, and also alphanumerics. How can I check for only dashes
> and spaces and return invalid when the user inputs alphanumerics?
> Thanks.
>
>
> Sub ValidateCCNumber( s As Object, e As ServerValidateEventArgs )
> Dim intCounter As Integer
> Dim strCCNumber As String
> Dim blnIsEven As Boolean = False
> Dim strDigits As String = ""
> Dim intCheckSum As Integer = 0
>
> 'Strip away everything except numerals
> FOR intCounter = 1 To Len( e.Value )
> IF IsNumeric( MID( e.Value, intCounter, 1 ) ) THEN
> strCCNumber = strCCNumber & MID( e.Value, intCounter, 1 )
> END IF
> NEXT
>
> 'IF nothing left, then fail
> IF Len( strCCNumber ) = 0 THEN
> e.IsValid = False
> ELSE
>
> 'Double every other digit
> FOR intCounter = Len( strCCNumber ) To 1 Step -1
> IF blnIsEven THEN
> strDigits = strDigits & cINT( MID( strCCNumber, intCounter, 1 )
> ) * 2
> ELSE
> strDigits = strDigits & cINT( MID( strCCNumber, intCounter, 1 )
> )
> END IF
> blnIsEven = ( NOT blnIsEven )
> NEXT
>
> 'Calculate CheckSum
> FOR intCounter = 1 To Len( strDigits )
> intCheckSum = intCheckSum + cINT( MID( strDigits, intCounter, 1
> ) )
> NEXT
>
> 'Assign results
> e.IsValid = (( intCheckSum Mod 10 ) = 0 )
>
> END IF
> END Sub
>