How to change index of elements in array of objects according to another array JavaScript?

Question

I have two arrays and need to change the order of elements in a way to be similar. by property c. i should get index of object of property c: 2 for example and place it to the right index in arrB . JavaScript

const arrA= [{
    a: 1,
    b: [{
        c: 2,
        d: 3
      },
      {
        c: 5,
        f: 6
      }
    ]
  },
  {
    a: 2,
    b: [{
        c: 2,
        d: 3
      },
      {
        c: 5,
        f: 6
      }
    ]
  }
];

const arrB = [{
    a: 1,
    b: [{
        c: 5,
        f: 6
      },
      {
        c: 2,
        d: 3
      },
    ]
  },
  {
    a: 2,
    b: [{
        c: 5,
        f: 6
      },
      {
        c: 2,
        d: 3
      },
    ]
  }
];

What I need is to sort arrB in order of all elements in key b to have the same order like in arrA. in reality this object contain more fields and they aren't similar. but they have the same property c by which i should change the order

const arrB= [{
    a: 1,
    b: [{
        c: 2,
        d: 3
      },
      {
        c: 5,
        f: 6
      }
    ]
  },
  {
    a: 2,
    b: [{
        c: 2,
        d: 3
      },
      {
        c: 5,
        f: 6
      }
    ]
  }
];

@Barmar, not properties, but objects. have added this to question — Лунатик, Dec 27 '22 at 00:25
You still can't change the property order from `{d: 3, c: 2}` to `{c: 2, d: 3}`. — Barmar, Dec 27 '22 at 00:27
@Barmar, because in reality they are not similar and have some additional properties — Лунатик, Dec 27 '22 at 00:38
In that case you need to specify how we're supposed to match the objects between the two arrays. — Barmar, Dec 27 '22 at 00:39
@Barmar, by property c. i should get index of object of property c: 2 for example and place it to the right index in arrB — Лунатик, Dec 27 '22 at 00:49
Do you want to sort by property `c`, or get the same array sequence in `arrB` like in `arrA`. If the latter case, do `arrA` and `arrB`, as well as property `b` within it have the same length, and same `c` property values (just on different order)? — Peter Thoeny, Dec 27 '22 at 01:02

score 0 · Accepted Answer · answered Dec 27 '22 at 00:55

You can use sort() to order the elements based on the indexes of the matching elements in arrA[i].b.

const arrA = [{
    a: 1,
    b: [{
        c: 2,
        d: 3
      },
      {
        c: 5,
        f: 6
      }
    ]
  },
  {
    a: 2,
    b: [{
        c: 2,
        d: 3
      },
      {
        c: 5,
        f: 6
      }
    ]
  }
];

const arrB = [{
    a: 1,
    b: [{
        c: 5,
        f: 6
      },
      {
        c: 2,
        d: 3
      },
    ]
  },
  {
    a: 2,
    b: [{
        c: 5,
        f: 6
      },
      {
        c: 2,
        d: 3
      },
    ]
  }
];

arrB.forEach((item, i) =>
  item.b.sort((el1, el2) => arrA[i].b.findIndex(el => el.c == el1.c) - arrA[i].b.findIndex(el => el.c == el2.c)));

console.log(arrB);

How to change index of elements in array of objects according to another array JavaScript?

1 Answers1