how to know credit card - Printable Version

PHP Code:
<?php
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * ------------------------------------------------------------------------
 * Editor   : PhpStorm 10.0.2
 * Date     : 12/16/2015
 * Time     : 11:45 AM
 * Authors  : Raymond L King Sr.
 * ------------------------------------------------------------------------
 * 
 * Class        creditcard_helper
 * 
 * @project     Fx
 * @author      Raymond L King Sr.
 * @link        http://www.procoversfx.com
 * @copyright   Copyright (c) 2009 - 2015 Pro Covers FX, LLC.
 * @license     http://www.procoversfx.com/license
 * ------------------------------------------------------------------------
 */

/**
 * card_type ()
 * ------------------------------------------------------------------------
 *
 * Return  credit card type if card number is valid
 *
 * @param  $card_number string
 * @return string
 **/
if ( ! function_exists('card_type'))
{
    /**
     * ------------------------------------------------------------------------
     * card_type ()
     * ------------------------------------------------------------------------
     *
     * @param  $card_number
     * @return string
     */
    function card_type($card_number)
    {
        $card_number = preg_replace('/[^\d]/', '', $card_number);

        if (preg_match('/^3[47][0-9]{13}$/', $card_number))
        {
            return 'American Express';
        }
        elseif (preg_match('/^3(?:0[0-5]|[68][0-9])[0-9]{11}$/', $card_number))
        {
            return 'Diners Club';
        }
        elseif (preg_match('/^6(?:011|5[0-9][0-9])[0-9]{12}$/', $card_number))
        {
            return 'Discover';
        }
        elseif (preg_match('/^(?:2131|1800|35\d{3})\d{11}$/', $card_number))
        {
            return 'JCB';
        }
        elseif (preg_match('/^5[1-5][0-9]{14}$/', $card_number))
        {
            return 'MasterCard';
        }
        elseif (preg_match('/^4[0-9]{12}(?:[0-9]{3})?$/', $card_number))
        {
            return 'Visa';
        }
        else
        {
            return 'Unknown';
        }
    }
}

/**
 * ------------------------------------------------------------------------
 * Filename: creditcard_helper.php
 * Location: ./application/helpers/creditcard_helper.php
 * ------------------------------------------------------------------------
 */