TypeScript- Extract values from array in array

Question

I have an array like that :

[{
        "id": 1,
        "city": [{
                "name": "BERLIN",
            }
        ],
    }, {
        "id": 2,
        "city": [{
                "name": "PARIS",
            }
        ],
    }, {
        "id": 3,
        "city": [{
                "name": "LONDON",
            }, {
                "name": "EXETER",
            }
        ],
    }

And I would like extract the values below :

[
    {id: 1, city: {name: "BERLIN"}, 
    {id: 2, city: {name: "PARIS"},
    {id: 3, city: {name: "LONDON"},
    {id: 3, city: {name: "EXETER"} 
]

I tried with and two map but, I don't have the result expected.

Can you help me for this issue.

Thank you.

@RobbyCornelissen: sorry, mistake of me, I fixed

Heptagram
– Heptagram

2021-03-15 23:55:47 +00:00
Commented Mar 15, 2021 at 23:55 — Heptagram
– Heptagram, Commented Mar 15, 2021 at 23:55

Robby Cornelissen · Accepted Answer · 2021-03-15 23:57:45Z

3

You can use flatMap() for this:

const a = [{
  "id": 1,
  "city": [{
    "name": "BERLIN",
  }],
}, {
  "id": 2,
  "city": [{
    "name": "PARIS",
  }],
}, {
  "id": 3,
  "city": [{
    "name": "LONDON",
  }, {
    "name": "EXETER",
  }],
}];

const result = a.flatMap(({id, city}) => city.map(c => ({id, city: c})));

console.log(result);

answered Mar 15, 2021 at 23:57

Robby Cornelissen

98.6k23 gold badges154 silver badges180 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Heptagram Over a year ago

Sorry, but I don't have flatmap in my angular project...

Robby Cornelissen Over a year ago

See here.

Collectives™ on Stack Overflow

TypeScript- Extract values from array in array

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related