/** * validate_VAT. * * @return mixed: bool (true if VAT is valid, false otherwise) on success, null otherwise */ function validate_VAT( $country_code, $vat_number ) { $client = new SoapClient( 'http://ec.europa.eu/taxation_customs/vies/checkVatService.wsdl' ); $result = $client->checkVat( array( 'countryCode' => $country_code, 'vatNumber' => $vat_number, ) ); return ( isset( $result->valid ) ) ? $result->valid : null; }