frontend\modules\topic\models\Topic::findTopic PHP Method

    public static function findTopic($id)
    {
        return static::findModel($id, ['>=', 'status', self::STATUS_ACTIVE]);
    }

 /**
  * 创建评论
  * @param $id
  * @return PostComment|\yii\web\Response
  */
 public function actionCreate($id)
 {
     $post = Topic::findTopic($id);
     $model = new PostComment();
     if ($model->load(Yii::$app->request->post())) {
         $topService = new TopicService();
         if (!$topService->filterContent($model->comment)) {
             $this->flash('回复内容请勿回复无意义的内容，如你想收藏或赞等功能，请直接操作这篇帖子。', 'warning');
             return $this->redirect(['/topic/default/view', 'id' => $id]);
         }
         $model->user_id = Yii::$app->user->id;
         $model->post_id = $id;
         $model->ip = Yii::$app->getRequest()->getUserIP();
         $rawComment = $model->comment;
         $model->comment = $model->replace($rawComment);
         if ($model->save()) {
             (new UserMeta())->saveNewMeta('topic', $id, 'follow');
             (new NotificationService())->newReplyNotify(Yii::$app->user->identity, $post, $model, $rawComment);
             // 更新回复时间
             $post->lastCommentToUpdate(Yii::$app->user->identity->username);
             // 评论计数器
             Topic::updateAllCounters(['comment_count' => 1], ['id' => $post->id]);
             // 更新个人总统计
             UserInfo::updateAllCounters(['comment_count' => 1], ['user_id' => $model->user_id]);
             $this->flash("评论成功", 'success');
         } else {
             $this->flash(array_values($model->getFirstErrors())[0], 'warning');
         }
         return $this->redirect(['/topic/default/view', 'id' => $post->id]);
     }
     return $model;
 }