RxJS dynamic source of observables

问题

I want to create an Observable of many observables (merge them). This could be achieved with merge(...arrayOfObservables). The problem is that some time this array will be changed and the observable should subscribe to the new observables, too.

回答1:

You can push new Observables to an array and then emit the array and subscribe to them with switchMap.

import { of, merge, BehaviorSubject } from 'rxjs'; 
import { switchMap } from 'rxjs/operators';

const s = new BehaviorSubject([of(1), of(2), of(3)]);

s.pipe(
  switchMap(array => merge(...array)),
).subscribe(x => console.log(x));

s.next([...s.getValue(), of(4)]);

Live demo: https://stackblitz.com/edit/rxjs-vmcqs9

来源：https://stackoverflow.com/questions/59916768/rxjs-dynamic-source-of-observables