Backend\Core\Engine\Ajax::setLanguage PHP Метод

    public function setLanguage($language)
    {
        // get the possible languages
        $possibleLanguages = BackendLanguage::getWorkingLanguages();
        // validate
        if (!array_key_exists($language, $possibleLanguages)) {
            throw new Exception('Language invalid.');
        }
        // set working language
        BackendLanguage::setWorkingLanguage($language);
    }