How to map array into an object in javascript

Question

How to map array into object in JavaScript? For example how to map this

{
  name: [1,2,3,4,5,6],
  uv: [300,-145,-100,-8,100,9],
  pv: [456,230,345,450,312,235]
}

into this

data = [
  {name: '1', uv: 300, pv: 456},
  {name: '2', uv: -145, pv: 230},
  {name: '3', uv: -100, pv: 345},
  {name: '4', uv: -8, pv: 450},
  {name: '5', uv: 100, pv: 321},
  {name: '6', uv: 9, pv: 235}
]

in JavaScript

Possible duplicate of [Converting JSON Object into Javascript array](https://stackoverflow.com/questions/20881213/converting-json-object-into-javascript-array) — Kevin Kloet, Sep 21 '17 at 12:12

score 2 · Accepted Answer · answered Sep 21 '17 at 12:13

2

You can use array#map

var obj = {
 name:[1,2,3,4,5,6],
 uv:[300,-145,-100,-8,100,9],
 pv:[456,230,345,450,312,235]
};

var result = obj.name.map(function(v,i){
  return {name: v, uv: obj.uv[i], pv: obj.pv[i]};
});

console.log(result);

answered Sep 21 '17 at 12:13

Hassan Imam

21,956
5
41
51

score 0 · Answer 2 · answered Sep 21 '17 at 12:11

0

Somehow like this:

var first = {
 name:[1,2,3,4,5,6],
 uv:[300,-145,-100,-8,100,9],
 pv:[456,230,345,450,312,235]
}

var data = [];

first.name.forEach((item, i) => {
  data.push({
    name: first.name[i],
    uv: first.uv[i],
    pv: first.pv[i]
  })
})

console.log(data)

answered Sep 21 '17 at 12:11

P.S.

15,970
14
62
86

This will only work when length of name, uv and pv is same. Else we will start getting undefined. – Tavish Aggarwal Sep 21 '17 at 12:13
@TavishAggarwal, yes, but in OP question they have the same length, I wrote this code based on OP's question. If they will have different length, we need to write another code. – P.S. Sep 21 '17 at 12:15
Yes. True! But its better to give generalize approach.. :-D – Tavish Aggarwal Sep 21 '17 at 12:16

score 0 · Answer 3 · answered Sep 21 '17 at 12:13

You could iterate the keys and then the properties and assign at each index the wanted values.

This works with an arbitrary count of properties without knowing in advance.

var data = { name: [1, 2, 3, 4, 5, 6], uv: [300, -145, -100, -8, 100, 9], pv: [456, 230, 345, 450, 312, 235] },
    result = Object
        .keys(data)
        .reduce((r, k) => (data[k].forEach((v, i) => (r[i] = r[i] || {})[k] = v), r), []);
    
console.log(result);

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How to map array into an object in javascript

3 Answers3