Example 1: Execute callback function when the observable completes
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import { interval } from 'rxjs';import { take, finalize } from 'rxjs/operators';//emit value in sequence every 1 secondconst source = interval(1000);//output: 0,1,2,3,4,5....const example = source.pipe(take(5), //take only the first 5 valuesfinalize(() => console.log('Sequence complete')) // Execute when the observable completes)const subscribe = example.subscribe(val => console.log(val));
finalize
📰 - Official docs
📁 Source Code: https://github.com/ReactiveX/rxjs/blob/master/src/internal/operators/finalize.ts