Yii::$app->response->headers->set('Content-Type', 'application/vnd.ms-excel');
 Yii::$app->response->format = Response::FORMAT_RAW;
....
        if (isset($_SERVER['WINDIR']))
        {
            $uploadPath = Yii::getAlias('@webroot')  . '/' . $path;
        }
        return file_get_contents($uploadPath);

  console.log("Trying download link method with simulated click ...");
                   

                                var blob = new Blob([data], { type: 'application/vnd.ms-excel' });
                                var url = urlCreator.createObjectURL(blob);

                                console.log(contentType, reader.readAsDataURL(blob));
                                link.setAttribute('href', url);

                                // Set the download attribute (Supported in Chrome 14+ / Firefox 20+)
                                link.setAttribute("download", filename);

                      
                                var event = document.createEvent('MouseEvents');
                                event.initMouseEvent('click', true, true, window, 1, 0, 0, 0, 0, false, false, false, false, 0, null);
                                link.dispatchEvent(event);
                          
                                console.log("Download link method with simulated click succeeded");