public function request($variable)
    {
        $order = ini_get('request_order');

        if (empty($order)) {
            $order = ini_get('variables_order');
        }

        $len = strlen($order);

        for ($i = 0; $i < $len; ++$i) {
            $character = strtoupper($order[$i]);

            if ($character == 'G') {
                if ($this->get($variable)) return $this->get($variable);
            } else if ($character == 'P') {
                if ($this->post($variable)) return $this->post($variable);
            } else if ($character == 'C') {
                if ($this->cookie($variable)) return $this->cookie($variable);
            }
        }

        return null;
    }