public function actionDelete_uploaded_file()
 {
     if (Yii::$app->request->isAjax) {
         $id = $_POST['id'];
         $file_model = ProductFiles::find()->where(['id' => $id])->one();
         $name = $file_model->file_name;
         $response = [];
         if (!empty($file_model) && $file_model->delete()) {
             unlink(\Yii::getAlias('@webroot') . '/product_files/' . $name);
             $response['files'] = ['msg' => 'File deleted successfully'];
         } else {
             $response['files'] = ['msg' => 'File not found in database'];
         }
         return json_encode($response);
     }
 }