javascript - 在 REST 调用中访问数组

Question

这个问题已经有答案了:

Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference (7 个回答)

已关闭 7 年前。

我有下面的代码，我在其中声明了数组 var filteredArray = []; 。我使用filteredArray将数据推送到Rest调用的回调函数中(这发生在for循环内)。一旦for循环结束。我想将filteredArray发送到我的 Angular Controller 。这是我的代码。当我将 console.log(filteredArray) 放在 for 循环之外时，我得到一个空数组。有人可以帮忙吗？

assignedToMe: function(req, res) {
  CustomerUser.find({
    userEmail: {
      $in: req.body.userEmail
    }
  }, function(err, docs) {

    var filteredArray = [];
    for (var i = 0; i < docs.length; i++) {
      var url = config.pythiaApi + config.pythiaApiPrefix + '/quotes/' + docs[i]['quoteId'];
      if (req.originalUrl.lastIndexOf('?') !== -1) {
        url += req.originalUrl.substr(req.originalUrl.lastIndexOf('?'));
      }
      restClient.get(url, function(body, response) {
        filteredArray.push(body.data)
      })
    }

    console.log(filteredArray) // Gives empty array
    res.status(200).json({});

  });
}

Answer 1

使用异步循环进行异步调用。例如async.times

assignedToMe: function(req, res) {
    CustomerUser.find({
        userEmail: {$in: req.body.userEmail}
    }, function(err, docs) {
        var filteredArray = [];
        async.times(docs.length, function(i, next){
            if(err) return next(err);
            var url = config.pythiaApi + config.pythiaApiPrefix + '/quotes/'+docs[i]['quoteId'];
            if (req.originalUrl.lastIndexOf('?') !== -1) {
                url += req.originalUrl.substr(req.originalUrl.lastIndexOf('?'));
            }
            restClient.get(url, function (body, response) {
                next(null, body.data)
            })
        }, function(err, result){
            // result contains your array
            res.status(200).json({});
        })
    });
}