What is the best solution to nested subscribe methods

Question

I have for example two nested subscribe methods.Sometimes i have more then two and they need to be connected,so when the first ends then the second should start etc... What is the best solution so they can wait other one,but not to be nested on this way ?

this.userService.postUser(userModel).subscribe(postUser => {
     this.userService.getAllUsers().subscribe(users => {
     })
})

naeramarth7 · Answer 1 · 2020-08-11T08:37:40.150

-1

If they need to run in sequence, you could make use of the switchMap operator:

this.userService
  .postUser(userModel)
  .pipe(switchMap((postUser /* unused? */) => this.userService.getAllUsers()))
  .subscribe(users => { })

edited Aug 11 '20 at 08:37

answered Aug 11 '20 at 08:25

naeramarth7

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This would not work, you need to use one of the flattening operators instead of the map operator, for example mergeMap or switchMap. – SnorreDan Aug 11 '20 at 08:33
My bad – i was looking for switchMap indeed. – naeramarth7 Aug 11 '20 at 08:37

What is the best solution to nested subscribe methods

1 Answers1