Iterate through nested JSON object array and store as key-value pair

Question

I have to iterate through this JSON:

{
  "data": 321563,
  "group": [
    {
      "added": 42421,
      "normal": {
        "x": 39,
        "y": "0.1300",
        "b": "0.4326",
        "c": "0.0552",
        "f": 166833
      },
      "j": "240313",
      "b": "0.2251",
      "a": "dda",
      "b": "0.101",
      "a": 922,
      "f": {
        "c": 39,
        "d": "0.263",
        "a": "2.8955",
        "h": "0.3211",
        "d": 274
      },
      "a": false,
      "k": 5,
      "w": "0.072",
      "d": "0.045",
      "e": 3
    },

I only want the j and k stored like a key value pair eg "j":k

I need to loop all of it, and store it to a file.

Answer 1

You can use a map to get a new array of items, this will not affect the old array.

 const data = { "game_count": 8750, "sets": [ { "appid": "221540", "true_count": 9, "bgs_avg": "0.10", // Other data here }, { "appid": "123456", "true_count": 9, "bgs_avg": "0.20", // Other data here } ] } // Use "data.sets = data.sets.map(...)" to replace the data // The following will only assign to a new variable const newArray = data.sets.map(itm => { return {appid: itm.appid, true_count: itm.true_count} }) console.log(newArray) 

We can also take the data and assign it directly back to the original overwriting it just by using data.sets = data.sets.map(...) as seen here:

 const data = { "game_count": 8750, "sets": [ { "appid": "221540", "true_count": 9, "bgs_avg": "0.10", // Other data here }, { "appid": "123456", "true_count": 9, "bgs_avg": "0.20", // Other data here } ] } data.sets = data.sets.map(itm => { return {appid: itm.appid, true_count: itm.true_count} }) console.log(data) 

Answer 2

In simple javascript this should work -

let newObj = {}
for(let i=0; i<obj.group.length; i++){
  newObj[obj.group[i].j] = obj.group[i].k 
}

Where 'obj' is your object

newObj will be you new Object which will contain all the key value pair