dosamigos\selectize\InputWidget::registerClientScript PHP Метод

    public function registerClientScript()
    {
        $id = $this->options['id'];
        if ($this->loadUrl !== null) {
            $url = Url::to($this->loadUrl);
            $this->clientOptions['load'] = new JsExpression("function (query, callback) { if (!query.length) return callback(); \$.getJSON('{$url}', { query: query }, function (data) { callback(data); }).fail(function () { callback(); }); }");
        }
        $options = Json::encode($this->clientOptions);
        $view = $this->getView();
        SelectizeAsset::register($view);
        $view->registerJs("jQuery('#{$id}').selectize({$options});");
    }