How can I make an Array of Objects from n properties of n arrays in JS?

Question

I have two arrays like this:

const opciones = ['A', 'B', 'C', 'D'];
const valoracion = [true, false, false, false];

And the, I want to create a new Array of Objects from these two arrays, like this:

const respuestas = [
  {opc: 'A', val: true},
  {opc: 'B', val: false},
  {opc: 'C', val: false},
  {opc: 'D', val: false},
]

a simple `for` loop can do that, you can find easy tutorials of this on google and much probably many other already answered questions here in SO. Please, read [ask] and if you tried something and didn't achieve your goal, then return with a specific question — Calvin Nunes, Dec 18 '19 at 16:52

score 1 · Accepted Answer · answered Dec 18 '19 at 16:51

This is commonly called a "Zip" operation for obvious reasons, and is quite easy to do using map in javascript.

const opciones = ['A', 'B', 'C', 'D'];
const valoracion = [true, false, false, false];

var result = opciones.map( (v,i) => ({opc:v, val:valoracion[i]}));
console.log(result);

score 1 · Answer 2 · answered Dec 18 '19 at 16:51

1

You can use map function and transform first array into array of objects:

const result = opciones.map((item, index) => ({
  opc: item,
  val: valoracion[index]
}));

answered Dec 18 '19 at 16:51

demkovych

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score 0 · Answer 3 · answered Dec 18 '19 at 16:56

You could take a dynamic approach with an object with the wanted keys and values and reduce the object's entries.

const
    opc = ['A', 'B', 'C', 'D'],
    val = [true, false, false, false],
    result = Object
        .entries({ opc, val })
        .reduce((r, [k, a]) => a.map((v, i) => Object.assign(r[i] || {}, { [k]: v })), []);

console.log(result);

How can I make an Array of Objects from n properties of n arrays in JS?

3 Answers3