Javascript group.json 键值进入列表

Question

I have the following json file structure that includes years from 2008 to 2020, along with other keys such as location, name, etc.:

{"2008": 50, "2009": 60, "2010": 70, "2011": 80, etc...}

I am trying to group the years into another key and adding it to the original array:

{metric:
    [{"year": 2008, "perc": 50},
     {"year": 2009, "perc": 60},
     {"year": 2010, "perc": 70},
     {"year": 2011, "perc": 80}],
 "2008": 50, 
 "2009": 60,
 "2010": 70,
 "2011": 80,
 etc...
}

I think I need to create a range between 2008 to 2020, and if I detect a key that's within that range, I add to the metrics group and add that to the array?

Answer 1

What you have is an object, not an array. You can use a for-in loop or a for-of loop on Object.entries or similar to loop through the object, and then it's a matter of converting the year to a number and comparing it to your range and if it's in range, adding it to the metric array:

 const data = {"2008": 50, "2009": 60, "2010": 70, "2011": 80, "2001": 20, "2002:": 30}; // Loop through the object for (const [year, perc] of Object.entries(data)) { // Get the year as a number const yearValue = +year; // See note below if (yearValue >= 2008 && yearValue <= 2020) { // It's in range, get or create the `metric` array const metric = data.metric?? (data.metric = []); // Add to it metric.push({year, perc}); } } console.log(data);

(I added a couple of out-of-range years there to show the range working.)

Using unary + to convert to number is just one of your options, I go through the full range of them in my answer here .

Answer 2

you need to loop though the object and create a new one

const group => obj {
    // create init object
    let output = {
        metric: []
    }

    // start loop
    for (const key in obj) {

        // check if object contains property
        if (Object.hasOwnProperty.call(obj, key)) {

            // check if key matches range and assign to metric if not
            if (!(/20(0[8-9]|1[0-9]|20)/gm).test(key)) output.metric.push({
                'year': key,
                'perc': obj[key]
            });
                
            //assign value if matches between 2008 to 2020
            else output[key] = obj[key]
        }
    }

    // return new object
    return output;
}