在 Javascript 中解构 json 对象

Question

How would access the _id and state values?

Here's the data

{
    "data": {
        "totalSamplesTested": "578841",
        "totalConfirmedCases": 61307,
        "totalActiveCases": 3627,
        "discharged": 56557,
        "death": 1123,
        "states": [
            {
                "state": "Lagos",
                "_id": "O3F8Nr2qg",
                "confirmedCases": 20555,
                "casesOnAdmission": 934,
                "discharged": 19414,
                "death": 207
            },
            {
                "state": "FCT",
                "_id": "QFlGp4md3y",
                "confirmedCases": 5910,
                "casesOnAdmission": 542,
                "discharged": 5289,
                "death": 79
            }
        ]
    }
}

Answer 1

What you have shown is a string in JSON format. You can convert that to a JavaScript object and then start to get the values you need from it.

let str = ‘{
    "data": {
        "totalSamplesTested": "578841",
        "totalConfirmedCases": 61307,
        "totalActiveCases": 3627,
        "discharged": 56557,
        "death": 1123,
        "states": [
            {
                "state": "Lagos",
                "_id": "O3F8Nr2qg",
                "confirmedCases": 20555,
                "casesOnAdmission": 934,
                "discharged": 19414,
                "death": 207
            },
            {
                "state": "FCT",
                "_id": "QFlGp4md3y",
                "confirmedCases": 5910,
                "casesOnAdmission": 542,
                "discharged": 5289,
                "death": 79
            }
        ]
    }
} ‘;

(Note, I have put the string in single quotes so it can be shown properly here but in your code you need to put it in back ticks so it can span many lines)

Now convert it to a JavaScript object.

let obj = JSON.parse(str);

Now look closely at the string to see how the object is structured. It actually has just one item in it, data. And that is itself an object with several items, one of which is states which is an array.

So, obj.data.states[0] is the array's first entry. That is an object and has _id and state items.

You can step through the array extracting the ._id and .state entries.