从 json 获取值到 JavaScript

Question

If I have some json like this:

{
    "dcf93893d83e4f28953f140b9cba1963":{
       "foo":{
          "client":"127.0.0.1",
          "id":"31971",
          "start time":1654131724.160335
       },
       "bar":{
          "client":"127.0.0.1",
          "id":"23456",
          "start time":1654131900.997766
       }
    }
 }

I figured out how to loop through it like this:

for (var key in json) {
    if (json.hasOwnProperty(key)) {
        console.log(json[key])
    }
}

How can I loop through each sub element (foo and bar in this case) and then fetch a key, for example id?

client, id and start time are the only known key names

Expected output:

31971
23456

EDIT: The json comes from fetch:

setInterval(function () {
    fetch(<url>)
        .then(function (response) {
            return response.json();
        })
        .then(function (json) {
            for (var key in json) {
                if (json.hasOwnProperty(key)) {
                    console.log(json[key])
                }
            }
        })
}, 2000);

Answer 1

Do another loop and grab the inner values by key name:

 const json = { "dcf93893d83e4f28953f140b9cba1963":{ "foo":{ "client":"127.0.0.1", "id":"31971", "start time":1654131724.160335 }, "bar":{ "client":"127.0.0.1", "id":"23456", "start time":1654131900.997766 } } } for (var key in json) { if (json.hasOwnProperty(key)) { //console.log(json[key]) for(var key2 in json[key]) { console.log(json[key][key2]["id"]) } } }

Answer 2

You have to loop in each loop. and save each id into an array.

var ids = []
for (var key in json) {
    if (json.hasOwnProperty(key)) {
        for(var obj in json[key]) {
           if (obj.id) ids.push(obj.id)
        }
    }
}

Answer 3

Instead of iterating, you could just get the object's values with Object.values() , and map those accordingly using flatMap() and map() :

 const data = { "dcf93893d83e4f28953f140b9cba1963": { "foo": { "client": "127.0.0.1", "id": "31971", "start time": 1654131724.160335 }, "bar": { "client": "127.0.0.1", "id": "23456", "start time": 1654131900.997766 } } }; const result = Object.values(data).flatMap(v => Object.values(v)).map(({id}) => id); console.log(result);