public function hasErrors($error_names = null) {
		if (empty($error_names)) {
			return !empty($this->errors['flag_error_in_fields']) || !empty($this->errors['general']['danger']);
		} else {
			if (!is_array($error_names)) {
				$error_names = [$error_names];
			}
			foreach ($error_names as $v) {
				if (!empty($this->errors['fields'][$v]['danger'])) {
					return true;
				}
			}
			return false;
		}
	}