protected function isValidOrder($order='')
    {
        return ( strlen($order) >= 4 && strlen($order) <= 12 && is_numeric(substr($order, 0, 4)) )?true:false;

    }
protected function isValidOrder($order='')
    {
        return ( strlen($order) >= 4 && strlen($order) <= 12 && is_numeric(substr($order, 0, 4)) )?true:false;

    }
protected function isValidOrder ( $ order = '' ) { return ( strlen ( $ order ) >= 4 && strlen ( $ order ) <= 12 && is_numeric ( substr ( $ order , 0 , 4 ) ) ) ? true : false ; }
Check is order is valid

@param string $order
@return boolean
Check is order is valid