How to create single object with multiple keys and elements?

Question

I have one array with key and its array elements

When I am converting it from array to object then I am getting index 0 and 1 but here I need index should be array1 and array2

 let input = [{ "array1": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" }] }, { "array2": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" } ] } ]; function convert(arr) { let obj = new Object(); arr.forEach((value, key) => { obj = value; }); return obj; } console.log(convert(input)) 

so after calling this function i am getting following output

{
  "array2": [
     {
      "id": 1,
      "name": "Test 1"
     },
    {
      "id": 2,
      "name": "Test 2"
    }
  ]
}

but here I need output should be like this

{
  "array1": [
    {
      "id": 1,
      "name": "Test 1"
    },
    {
      "id": 2,
      "name": "Test 2"
    }
  ],
  "array2": [
    {
      "id": 1,
      "name": "Test 1"
    },
    {
      "id": 2,
      "name": "Test 2"
    }
  ]
}

If I use the define the array inside the convert function and push it then again i am getting the index 0 and 1.

How can i get expected result here.

Answer 1

For getting a single object with the wanted keys, you could assign all items to a single object with Object.assign with spread syntax ... .

 let input = [{ array1: [{ id: 1, name: "Test 1" }, { id: 2, name: "Test 2" }] }, { array2: [{ id: 1, name: "Test 1" }, { id: 2, name: "Test 2" }] }], object = Object.assign(...input); console.log(object) 

 .as-console-wrapper { max-height: 100% !important; top: 0; } 

---

Your code does not work because you take the latest assignment as a result

function convert(arr) {
    let obj = new Object();       // initialization

    arr.forEach((value, key) => {
        obj = value;              // assignment
    });
    return obj;                   // returns last assignment
}

Answer 2

Spreading ( ... ) is the key:

 let input = [{ "array1": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" }] }, { "array2": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" } ] } ]; function convert(arr) { return arr.reduce((acc, curr) => ({ ...acc, ...curr }), {}); } console.log(convert(input)) 

 .as-console-wrapper { max-height: 100% !important; top: auto; } 

You could also combine it with Object.assign on the array itself:

 let input = [{ "array1": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" }] }, { "array2": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" } ] } ]; function convert(arr) { return Object.assign(...arr); } console.log(convert(input)) 

 .as-console-wrapper { max-height: 100% !important; top: auto; } 

Answer 3

Using your code

function convert(arr) {
   let obj = new Object();
   arr.forEach((value, key) => {
     obj[key] = value;
   });
   return obj;
}

You were doing obj = value; on each iteration in the forEach which would mean you reassign obj to be the new value every time.

Answer 4

You just need to use your key parameter of foreach function in your object. I am attaching the code below you can look.

 let input = [{ "array1": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" }] }, { "array2": [{ "id": 1, "name": "Test 1" }, { "id": 2, "name": "Test 2" } ] } ]; function convert(arr) { let obj = new Object(); arr.forEach((value, key) => { obj[key] = value; }); return obj; } console.log(convert(input))