javascript - 谷歌地图和访问返回的对象

Question

这几乎可以肯定是超级基本的东西，但我一辈子都无法找出问题所在。我有一个从 Google Maps JS API 返回的数据对象

    {
   "destination_addresses" : [ "12 Ansell Rd, London SW17, UK" ],
   "origin_addresses" : [
      "911 Alfreds Way, Barking IG11 0AX, UK",
      "911 Alfreds Way, Barking IG11 0AX, UK",
      "50 Buttesland St, Hoxton, London N1 6BY, UK"
   ],
   "rows" : [
      {
         "elements" : [
            {
               "distance" : {
                  "text" : "24.4 km",
                  "value" : 24411
               },
               "duration" : {
                  "text" : "55 mins",
                  "value" : 3297
               },
               "duration_in_traffic" : {
                  "text" : "58 mins",
                  "value" : 3454
               },
               "status" : "OK"
            }
         ]
      },
      {
         "elements" : [
            {
               "distance" : {
                  "text" : "24.4 km",
                  "value" : 24411
               },
               "duration" : {
                  "text" : "55 mins",
                  "value" : 3297
               },
               "duration_in_traffic" : {
                  "text" : "58 mins",
                  "value" : 3454
               },
               "status" : "OK"
            }
         ]
      },
      {
         "elements" : [
            {
               "distance" : {
                  "text" : "13.9 km",
                  "value" : 13905
               },
               "duration" : {
                  "text" : "48 mins",
                  "value" : 2909
               },
               "duration_in_traffic" : {
                  "text" : "45 mins",
                  "value" : 2717
               },
               "status" : "OK"
            }
         ]
      }
   ],
   "status" : "OK"
}

我正在使用 .get 和 require 的 https 模块来检索它，它工作得非常好，然后我像这样打印数据......

https.get(`https://maps.googleapis.com/maps/api/distancematrix/json?origins=51.5285,0.0847|51.5285,0.0847|51.5285,-0.0847&destinations=51.432622,-0.164496&departure_time=now&key=APIKEY`, (resp) => {

      let data = '';
        // A chunk of data has been recieved.
        resp.on('data', (chunk) => {
          data += chunk;
        });
        //When all data is received
        resp.on('end', () => {
            console.log(data);
        });

    });

问题是一旦我尝试访问（甚至只是控制台日志）对象中的任何数据，例如

data.destination_addresses

它返回未定义。我认为这可能与异步问题有关，但我可以打印数据变量而不是单独打印它的属性是没有意义的

标签： javascriptnode.jsgoogle-mapshttpsrequire

Answer 1

您需要先将其解析为 JSON

var obj = JSON.parse(data);
console.log(obj.destination_addresses);