Question

我编写了这个函数，它正确记录了我期望的值（仅限于一个partecipants id数组）：

getPartecipantsList: function(roomId){
        this._getPartecipants(roomId,function(err,data){
            partecipants_to_send = [];
            for (i=0; i< data.partecipants.length; i++){
                partecipants_to_send.push({ id : data.partecipants[i].id });
            }
            console.log(partecipants_to_send);
            return partecipants_to_send;
        });
    },

日志显示如下：

[{id：＆＃39; user1＆＃39; }，{id：＆＃39; user2＆＃39;}]

当我尝试从我的中间件调用此函数时，它没有显示相同的值（而是它给了我undefined）：

...
router.route('/:id/partecipants')
    .get(function(req,res){
        partecipants_list = RoomsManager.getPartecipantsList(req.room._id);
        console.log(partecipants_list);
....

如何获得我期望在中间件上获得的值？

此代码在Node.js后端运行

Answer 1

问题是你的return语句从匿名函数返回到this._getPartecipants，但是this._getPartecipants的结果没有返回给你。

尝试：

getPartecipantsList: function(roomId){
    return this._getPartecipants(roomId,function(err,data){
        partecipants_to_send = [];
        for (i=0; i< data.partecipants.length; i++){
            partecipants_to_send.push({ id : data.partecipants[i].id });
        }
        console.log(partecipants_to_send);
        return partecipants_to_send;
    });
},

未定义函数结果

1 个答案: