Ean8.php

<?php
/**
 * Zend Framework (http://framework.zend.com/)
 *
 * @link      http://github.com/zendframework/zf2 for the canonical source repository
 * @copyright Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
 * @license   http://framework.zend.com/license/new-bsd New BSD License
 */

namespace Zend\Validator\Barcode;

class Ean8 extends AbstractAdapter
{
    /**
     * Constructor for this barcode adapter
     */
    public function __construct()
    {
        $this->setLength([7, 8]);
        $this->setCharacters('0123456789');
        $this->setChecksum('gtin');
    }

    /**
     * Overrides parent checkLength
     *
     * @param string $value Value
     * @return bool
     */
    public function hasValidLength($value)
    {
        if (strlen($value) == 7) {
            $this->useChecksum(false);
        } else {
            $this->useChecksum(true);
        }

        return parent::hasValidLength($value);
    }
}