RxJS5 - Operator to convert object map to array

Question

I have a service that returns an object map which is then used in Angular's ngFor which only takes arrays. So, I am using the map operator with lodash's _toArray to convert the data to an array.

Although this works, I then have to import lodash everywhere I need to do this and it seems brittle. I was going to look into creating a custom operator, but perhaps there is an operator that already does this? I can't seem to find the right one(s)

Data:

{ 0 : {data : 'lorem'}, 1 : {data : 'lorem'}, 2 : {data : 'lorem'} }

Current:

this.http
    .get('/api')
    .map(data => _.toArray(data));

Possible?

this.http
    .get('/api')
    .mapToArray();

You could use Angular in-built filter for this. Then you need import lodash only once into where your filter is defined. docs.angularjs.org/guide/filter — aarosil
– aarosil, Commented Jan 26, 2017 at 3:47

cartant · Accepted Answer · 2017-01-26 14:12:55Z

17

You should be able to do what you want with RxJS's map operator and just the Object.keys() method.

Rx.Observable
  .of({
    0: { data : 'lorem' },
    1: { data : 'lorem' },
    2: { data : 'lorem' }
  })
  .map(data => Object.keys(data).map(k => data[k]))
  .subscribe(data => console.log(data));

<script src="https://npmcdn.com/@reactivex/[email protected]/dist/global/Rx.min.js"></script>

edited Jan 26, 2017 at 14:12

cartant

58.6k17 gold badges169 silver badges201 bronze badges

answered Jan 26, 2017 at 4:33

cpt_redbeard

2153 silver badges6 bronze badges

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

4 Comments

cartant Over a year ago

That won't necessarily output an array with the elements in the correct order.

cpt_redbeard Over a year ago

Did I miss where the op wanted the array in a specific order? The reason I answered similar but different is for that exact reason. No need to code for specs that just aren't there.

Thibs Over a year ago

I did not need the array in order and this is a good alternative, which is what I was asking for. Thank-you

luiscla27 Over a year ago

Keeping the order of the attributes is tricky, basically, the only guaranteed way of doing it is to define a different array with the expected order and then reorder your result, read more here

Collectives™ on Stack Overflow

RxJS5 - Operator to convert object map to array

1 Answer 1

4 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related