ForkJoin 2 BehaviorSubjects

Question

I have two behaviour subject streams what I\'m trying to forkJoin with no luck. As I imagined it gives back the two last values of it. Is this possible to implement it someh

Answer 1

If you don't want (or don't know when) to call complete(), you may use combineLatest instead of forkJoin.

With combineLatest, anytime one of the source observables (in your case your behavior subjects) emits a value, combineLatest will trigger:

let stream1 = new BehaviorSubject(2);
let stream2 = new BehaviorSubject('two');

combineLatest(stream1, stream2)
    .subscribe(r => {
         console.log(r);
    });

stream1.next(3);
stream2.next('three');

Console log:

(2) [2, "two"] // initial state

(2) [3, "two"] // next triggered on stream1

(2) [3, "three"] // next triggered on stream2

Live demo: https://stackblitz.com/edit/rxjs-qzxo3n