public function checkRules($rules, Array $params = null)
    {
        if (is_string($rules)) {
            $rules = (array)explode(',', $rules);
        }

        foreach ($rules as $name) {
            if (!$this->hasRule($name) || !$this->getRule($name)->execute($this, $params)) {
                return false;
            }
        }

        return true;
    }