Angular applications heavily rely on RxJS Observables. While building large front end apps with these technologies we quickly will need to learn how to manage subscribing to multiple Observables in our components. In this post we are going to cover five different ways to subscribe to multiple Observables and the pros and cons of each.
In our component, we will have three Observables. Each Observable has slightly different behavior. The first Observable emits a single value immediately. The second Observable emits a single value after a couple of seconds. The third Observable emits multiple values one value every second. Below are some functions that return the Observables that we will use in our components.
import { Observable } from 'rxjs/Observable';
import { of } from 'rxjs/observable/of';