check VAT number

check_VAT_number.php

<?php

class Helper {

    /**
     * http://www.pfz.nl/wiki/invoer-validatie/#Geldig_BTW.2FVAT_nummer
     *
     * Look if the given input could be a legal VAT-number.
     * Accepts input with or without '.' between the numbers, must contain a County-code
     *
     * Note: This only checks the syntax, NOT IF THE VAT REALLY EXISTS OR IS ACTIVE!
     *
     * @author Sebastiaan Stok <[email protected]>
     *
     * @param string $psVatInput
     * @return bool
     */
    static function isVAT($psVatInput)
    {

        $psVatInput = trim($psVatInput);
        $psVatInput = str_replace('.', '', $psVatInput);
        $aVatMatch = array();

        // Common syntax
        if (!preg_match('/^([a-z]{2})[ ]*(.+)$/is', $psVatInput, $aVatMatch)) {
            return false;
        }

        $aVatMatch[1] = strtoupper($aVatMatch[1]);

        $functionName = 'isVAT_' . $aVatMatch[1];
        if (function_exists($functionName)) {
            return $functionName($psVatInput);
        }

//*************************************************        
//        BELGIAN VAT NUMBER
//        'BE'+10 digits, 
//        the first digit following the prefix is always zero ("0") 
//        – e.g. BE0999999999
//        
//*************************************************
        
        
        
        
        $aVatRegexes = array(
            'AT' => 'U[0-9]{8}',
            'BE' => '0[0-9]{9}',
            'BG' => '[0-9]{9,10}',
            'CY' => '[0-9]{8}[A-Za-z]',
            'CZ' => '[0-9]{8,10}',
            'DE' => '[0-9]{9}',
            'DK' => '[0-9]{2} ?[0-9]{2} ?[0-9]{2} ?[0-9]{2}',
            'EE' => '[0-9]{9}',
            'EL' => '[0-9]{9}',
            'ES' => '([A-Za-z0-9][0-9]{7}[A-Za-z0-9])',
            'FI' => '[0-9]{8}',
            'FR' => '[A-Za-z0-9]{2} ?[0-9]{9}',
            'GB' => '([0-9]{3} ?[0-9]{4} ?[0-9]{2}|[0-9]{3} ?[0-9]{4} ?[0-9]{2} ?[0-9]{3}|GD[0-9]{3}|HA[0-9]{3})',
            'HU' => '[0-8]{8}',
            'IE' => '[0-9][A-Za-z0-9+*][0-9]{5}[A-Za-z]',
            'IT' => '[0-9]{11}',
            'LT' => '([0-9]{9}|[0-9]{12})',
            'LU' => '[0-9]{8}',
            'LV' => '[0-9]{11}',
            'MT' => '[0-9]{8}',
            'NL' => '[0-9]{9}B[0-9]{2}',
            'PL' => '[0-9]{10}',
            'PT' => '[0-9]{9}',
            'RO' => '[0-9]{2,10}',
            'SE' => '[0-9]{12}',
            'SI' => '[0-9]{8}',
            'SK' => '[0-9]{10}',
        );
        
        if (!isset($aVatRegexes[$aVatMatch[1]]) || !preg_match('/^([a-z]{2})[ ]*' . $aVatRegexes[$aVatMatch[1]] . '$/is', $psVatInput)) {
            return false;
        }
        
        return true;
    }

}

?>