Convert multidimensional array to object while keeping the same structure

Question

I want to convert

let multiArr = [["r", "s", "p"], ["w", "u", "i"], ... , ["a", "t", "g"]]

to:

let multiObj = [{r: "0", s: "1", p: "2"}, {w: "0", u: "1", i: "2"}, ... , {a: "0", t: "1", g: "2"}]

This doesn't seem to work as it flattens the array into one-dimension. How do I keep the two-dimensional aspect of the object?

function toObject(arr) {
  let multiObj = {};
  for (let i = 0; i < arr.length; i++) {
    for (let j = 0; j < arr[i].length; j++) {
      let key = arr[i][j];
      let val = j;
      multiObj[key] = val;
    }
  }
  return multiObj;
}

Fixed. It should be `multiObj = {}` instead of `multiObj = []` — Julian, Oct 15 '22 at 19:50
Still invalid. Objects store key/value pairs. Current syntax is not a key/value pair. — Brent, Oct 15 '22 at 19:52
`{"r", "s", "p"}` doesn't exist as syntax construct. It would have to be something along the lines of `{foo: "r", bar: "s", baz: "p"}`. — CherryDT, Oct 15 '22 at 19:52
My apologies, fixed. I mixed up invalid with undefined. I thought you all meant that it returned undefined. — Julian, Oct 15 '22 at 19:55
Does this answer your question? [Convert Array to Object](https://stackoverflow.com/questions/4215737/convert-array-to-object) — pilchard, Oct 15 '22 at 20:56

Laaouatni Anas · Answer 1 · 2022-10-18T09:03:34.440

let multiArr = [
  ["r", "s", "p"],
  ["w", "u", "i"],
  ["a", "t", "g"],
];

console.log(
  toObject(multiArr)
);

<script>
  function toObject(arr) {
    let output = {}

    // child array => object
    arr.forEach((child, i) => {
      output[i] = {...child}
    })

    return output;
  }
</script>

expected result:

{
  "0": {
    "0": "r",
    "1": "s",
    "2": "p"
  },
  "1": {
    "0": "w",
    "1": "u",
    "2": "i"
  },
  "2": {
    "0": "a",
    "1": "t",
    "2": "g"
  }
}

and you can still access it like a array

toObject(arr)[0][0]  // "r"

//or

toObject(arr).1.2    // "i"

score 0 · Answer 2 · answered Nov 16 '22 at 08:17

You can use Array.prototype.reduce to transform your array into an array of different shape of an object

let data = [["r", "s", "p"], ["w", "u", "i"],["a", "t", "g"]]

const results = data.reduce((accumulator, current) => {
  let obj = current.reduce((acc, curr, index) => {
    acc[curr] =  index;
    return acc;
  }, {});
  accumulator = accumulator.concat(obj);
  return accumulator;
}, []);

console.log(results);

coderpolo · Accepted Answer · 2022-10-18T07:26:17.593

-1

here is what you are looking for :


let multiArr = [["r", "s", "p"], ["w", "u", "i"]];

var objs = multiArr.map(array => ({ 
  0: array[0],
  1: array[1],
  2: array[2],
}));

edited Oct 18 '22 at 07:26

answered Oct 15 '22 at 20:01

coderpolo

307
3
12

If you are not sure then why did you answer? Please provide an explanation for your answers too. Otherwise they are not very useful – Dharman Oct 17 '22 at 15:53
its not difficult to run the js in an emulator and see that its what the OP wanted but the keys need to be tweaked a bit, to you want the unit tests aswell or what :'D – coderpolo Oct 17 '22 at 19:54
Please read [answer]. – Dharman Oct 17 '22 at 19:58

Convert multidimensional array to object while keeping the same structure

3 Answers3