yii2模型

多对多可以使用all()来调用

对数据提供者进行修改

    /**
     * Lists all ArticleCate models.
     * @return mixed
     */
    public function actionIndex()
    {
        $searchModel = new ArticleCateSearch();
        $dataProvider = $searchModel->search(Yii::$app->request->queryParams);
        $dataProvider->setModels($this->getTree($dataProvider->getModels(), 0, 0));
        return $this->render('index', [
            'searchModel' => $searchModel,
            'dataProvider' => $dataProvider,
        ]);
    }

    public function getTree($data, $pid, $level = 0)
    {
        $list = array();
        foreach ($data as $k => $v) {
            if ($v['parent_id'] == $pid) {
                $v['name'] = '| — —' . str_repeat('| — —', $level) . $v['name'];
                $list[] = $v;
                $list = array_merge($list, self::getTree($data, $v['id'], $level + 1));
            }
        }
        return $list;
    }