Example 1: Ignore all elements from source
( StackBlitz | jsBin | jsFiddle )
// RxJS v6+import { interval } from 'rxjs';import { take, ignoreElements } from 'rxjs/operators';//emit value every 100msconst source = interval(100);//ignore everything but completeconst example = source.pipe(take(5), ignoreElements());//output: "COMPLETE!"const subscribe = example.subscribe(val => console.log(`NEXT: ${val}`),val => console.log(`ERROR: ${val}`),() => console.log('COMPLETE!'));
Example 2: Only displaying error
( StackBlitz | jsBin | jsFiddle )
// RxJS v6+import { interval, throwError, of } from 'rxjs';import { mergeMap, ignoreElements } from 'rxjs/operators';//emit value every 100msconst source = interval(100);//ignore everything but errorconst error = source.pipe(mergeMap(val => {if (val === 4) {return throwError(`ERROR AT ${val}`);}return of(val);}),ignoreElements());//output: "ERROR: ERROR AT 4"const subscribe = error.subscribe(val => console.log(`NEXT: ${val}`),val => console.log(`ERROR: ${val}`),() => console.log('SECOND COMPLETE!'));
ignoreElements 📰 - Official
docs
📁 Source Code: https://github.com/ReactiveX/rxjs/blob/master/src/internal/operators/ignoreElements.ts