Credit Card Identification and Validation Class

ISN (services de réseaux sociaux internationaux - applications interactives et sites web dynamiques)

Credit Card Identification and Validation Class

Credit Card Identification and Validation Class - The credit_card class

provides methods for cleaning, validating and identifying the type of credit card numbers.

<?php

class credit_card

{

function clean_no ($cc_no)

{

// Remove non-numeric characters from $cc_no

return ereg_replace ('[^0-9]+', '', $cc_no);

}

function identify ($cc_no)

{

$cc_no = credit_card::clean_no ($cc_no);

// Get card type based on prefix and length of card number

if (ereg ('^4(.{12}|.{15})$', $cc_no))

return 'Visa';

if (ereg ('^5[1-5].{14}$', $cc_no))

return 'Mastercard';

if (ereg ('^3[47].{13}$', $cc_no))

return 'American Express';

if (ereg ('^3(0[0-5].{11}|[68].{12})$', $cc_no))

return 'Diners Club/Carte Blanche';

if (ereg ('^6011.{12}$', $cc_no))

return 'Discover Card';

if (ereg ('^(3.{15}|(2131|1800).{11})$', $cc_no))

return 'JCB';

if (ereg ('^2(014|149).{11})$', $cc_no))

return 'enRoute';

return 'unknown';

}

function validate ($cc_no)

{

// Reverse and clean the number

$cc_no = strrev (credit_card::clean_no ($cc_no));

// VALIDATION ALGORITHM

// Loop through the number one digit at a time

// Double the value of every second digit (starting from the right)

// Concatenate the new values with the unaffected digits

for ($ndx = 0; $ndx < strlen ($cc_no); ++$ndx)

$digits .= ($ndx % 2) ? $cc_no[$ndx] * 2 : $cc_no[$ndx];

// Add all of the single digits together

for ($ndx = 0; $ndx < strlen ($digits); ++$ndx)

$sum += $digits[$ndx];

// Valid card numbers will be transformed into a multiple of 10

return ($sum % 10) ? FALSE : TRUE;

}

function check ($cc_no)

{

$valid = credit_card::validate ($cc_no);

$type = credit_card::identify ($cc_no);

return array ($valid, $type, 'valid' => $valid, 'type' => $type);

}