a连接用post方法请求action却执行了三遍 [ 2.0 版本 ]

现在情况是，我点了一下a 链接，actionTripDays 方法执行了三遍，表里被插入了三条数据，应该只执行一次，插入一条数据的，这是为毛呢？？求帮助

<a href="<?= Url::toRoute(['trip-days', 'id' => $logId, 'position' => 'end']) ?>" class="add-one-day" data-method="post" rel="nofollow">+ 新增后一天</a>


public function actionTripDays($id)
{
    $model = $this->findModel($id);

    // 最开始是这样写的，执行了两遍
    if (!empty($position = Yii::$app->request->get('position', '')))
 
    // 变成下面这样干脆执行了三遍
    if (Yii::$app->request->getIsPost() && !empty($position = Yii::$app->request->get('position', ''))) {
        // dump(Yii::$app->request->get('position', ''));
        // exit;
        TravelDay::addDay($position, $model->id);
    } else {
        TravelDay::initDay($model->id);
    }


    $days = TravelDay::find()
                ->where(['travel_log_id' => $model->id])
                ->orderBy(['order' => SORT_ASC])
                ->all();

    $images = TravelImg::find()
            ->where(['travel_log_id' => $model->id])
            ->orderBy(['order' => SORT_ASC])
            ->all();


    return $this->render('trip-days', [
            'images' => $images,
            'days' => $days,
            'logId' => $model->id,
        ]);
}