StaticcreateCreates a "subject" by basically gluing an observer to an observable.
Creates a new Observable with this Subject as the source. You can do this to create custom Observer-side logic of the Subject and conceal it from code that uses the Observable.
Observable that this Subject casts to.
Used as a NON-CANCELLABLE means of subscribing to an observable, for use with
APIs that expect promises, like async/await. You cannot unsubscribe from this.
WARNING: Only use this with observables you know will complete. If the source observable does not complete, you will end up with a promise that is hung up, and potentially all of the state of an async function hanging out in memory. To avoid this situation, look into adding something like timeout, take, takeWhile, or takeUntil amongst others.
import { interval, take } from 'rxjs';
const source$ = interval(1000).pipe(take(4));
async function getTotal() {
let total = 0;
await source$.forEach(value => {
total += value;
console.log('observable -> ' + value);
});
return total;
}
getTotal().then(
total => console.log('Total: ' + total)
);
// Expected:
// 'observable -> 0'
// 'observable -> 1'
// 'observable -> 2'
// 'observable -> 3'
// 'Total: 6'
A handler for each value emitted by the observable.
A promise that either resolves on observable completion or rejects with the handled error.
a handler for each value emitted by the observable
a constructor function used to instantiate the Promise
a promise that either resolves on observable completion or rejects with the handled error
Passing a Promise constructor will no longer be available in upcoming versions of RxJS. This is because it adds weight to the library, for very little benefit. If you need this functionality, it is recommended that you either polyfill Promise, or you create an adapter to convert the returned native promise to whatever promise implementation you wanted. Will be removed in v8.
Optionalnext: null | ((value: T) => void)Optionalerror: null | ((error: any) => void)Optionalcomplete: null | (() => void)Instead of passing separate callback arguments, use an observer argument. Signatures taking separate callback arguments will be removed in v8. Details: https://rxjs.dev/deprecations/subscribe-arguments
Replaced with firstValueFrom and lastValueFrom. Will be removed in v8. Details: https://rxjs.dev/deprecations/to-promise
Replaced with firstValueFrom and lastValueFrom. Will be removed in v8. Details: https://rxjs.dev/deprecations/to-promise
Replaced with firstValueFrom and lastValueFrom. Will be removed in v8. Details: https://rxjs.dev/deprecations/to-promise
A Subject is a special type of Observable that allows values to be multicasted to many Observers. Subjects are like EventEmitters.
Every Subject is an Observable and an Observer. You can subscribe to a Subject, and you can call next to feed values as well as error and complete.