What is the difference between Promises and Observables?

Question

What is the difference between Promise and Observable in Angular?

An example on each would be helpful in understanding both the cases. In w

Answer 1

There are lots of answers on this topic already so I wouldn't add a redundant one.

But to someone who just started learning Observable / Angular and wonders which one to use compare with Promise, I would recommend you keep everything Observable and convert all existing Promises in your project to Observable.

Simply because Angular framework itself and it's community are all using Observable. So it would be beneficial when you integrate framework services or 3rd party modules and chaining everything together.

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While I appreciate all the downvotes but I still insist my opinion above unless someone put a proper comment to list a few scenarios that might still be useful in your Angular project to use Promises over Observables.

Of course, no opinion is 100% correct in all cases but at least I think 98% of the time for regular commercial projects implemented in Angular framework, Observable is the right way to go.

Even if you don't like it at the starting point of your simple hobby project, you'll soon realise almost all components you interact with in Angular, and most of the Angular friendly 3rd party framework are using Observables, and then you'll ended up constantly converting your Promise to Observable in order to communicate with them.

Those components includes but not limited to: HttpClient, Form builder, Angular material modules/dialogs, Ngrx store/effects and ngx-bootstrap.

In fact, the only Promise from Angular eco-system I dealt with in the past 2 years is APP_INITIALIZER.