有大佬 解释下吗？我是用PHP调的

$accesstoken = D('AccessToken');

        $token = $accesstoken -> get_access_token();

        $url = 'https://api.weixin.qq.com/tcb/databasecollectionadd?access_token='.$token;

        $data = json_encode('env'=>'test-7n9e2','collection_name'=>'ceshi']);

        $res = $this->http_post_data($url, $data);

        return $this->toJson('Ok',$res);