I have an array like this:

[
  {
    0 : {
      id: 'somevalue',
      name: 'John Doe',
      age: '20'
    }
  }
  ...
]

I would like to modify the array, for example to set the key to the id attribute like this:

[
  {
    somevalue : {
      name: 'John Doe',
      age: '20'
    }
  }
]

What would be the best way to achieve this. Thanks for your time.

I have an array like this:

[
  {
    0 : {
      id: 'somevalue',
      name: 'John Doe',
      age: '20'
    }
  }
  ...
]

I would like to modify the array, for example to set the key to the id attribute like this:

[
  {
    somevalue : {
      name: 'John Doe',
      age: '20'
    }
  }
]

What would be the best way to achieve this. Thanks for your time.

• javascript
• arrays

• data.map(function(d) { let ref = d[0]; let id = ref.id; delete ref.id; return { [id]: ref }; }) – Rayon Commented May 22, 2020 at 10:45

5 Answers 5

You could destructure the object and take the wanted key out of the object. Then return new object with wanted value.

var array = [{ 0 : { id: 'somevalue', name: 'John Doe', age: '20' } }],
    key = 'id',
    result = array.map(({ 0: { [key]: k, ...o } }) => ({ [k]: o }));

console.log(result);

Assuming there is only one nested object, you can use the function map as follow:

let arr = [
  {
    0 : {
      id: 'somevalue',
      name: 'John Doe',
      age: '20'
    }
  }
];

let result = arr.map(o => {
  let [{id, ...rest}] = Object.values(o);
  return {[id]: rest};
});

console.log(result);

I guess you have just more then 1 Object. You can try it like this.

let data = [
  {
    0 : {
      id: 'somevalue',
      name: 'John Doe',
      age: '20'
    }
  }
]


let result = data.map((el, index) => {
   let id = el[index].id;
   delete el[index].id;
   return { [id]: {...el[index]}}
})

console.log(result);

You can try this if the key is always '0' in the given object

const arr = [
  {
    0 : {
      id: 'somevalue',
      name: 'John Doe',
      age: '20'
    }
  }
]

arr.map(item => {
    const value = {...item[0]};
    const key = value.id;
    delete value.id;
    return {
        [key]: value
    }
})

You can use map and reduce functions to achieve the desired output.

This solution will work even if you have more than one nested objects and if you have more properties in your nested objects, i.e. properties other than name and age

const arr = [
  {
    0: { id: "somevalue", name: "John Doe", age: "20" },
    1: { id: "somevalue 2", name: "John Doe", age: "20", gender: 'male' }
  },
  {
    0: { id: "somevalue 3", name: "John Doe", age: "20" },
    1: { id: "somevalue 4", name: "John Doe", age: "20", gender: 'male' },
    2: { id: "somevalue 5", name: "John Doe", age: "20" }
  }
];

const res = arr.map((obj) => {
  const v = Object.values(obj);

  return v.reduce((acc, curr) => {
    const {id, ...restProps } = curr;
    acc[curr.id] = restProps;
    
    return acc; 
  }, {});
});

console.log(res);

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