bufferTime
signature: bufferTime(bufferTimeSpan: number, bufferCreationInterval: number, scheduler: Scheduler): Observable
Collect emitted values until provided time has passed, emit as array.
Examples
Example 1: Buffer for 2 seconds
( StackBlitz | jsBin | jsFiddle )
// RxJS v6+
import { interval } from 'rxjs';
import { bufferTime } from 'rxjs/operators';
//Create an observable that emits a value every 500ms
const source = interval(500);
//After 2 seconds have passed, emit buffered values as an array
const example = source.pipe(bufferTime(2000));
//Print values to console
//ex. output [0,1,2]...[3,4,5,6]
const subscribe = example.subscribe(val =>
console.log('Buffered with Time:', val)
);
Example 2: Multiple active buffers
( StackBlitz | jsBin | jsFiddle )
// RxJS v6+
import { interval } from 'rxjs';
import { bufferTime } from 'rxjs/operators';
//Create an observable that emits a value every 500ms
const source = interval(500);
/*
bufferTime also takes second argument, when to start the next buffer (time in ms)
for instance, if we have a bufferTime of 2 seconds but second argument (bufferCreationInterval) of 1 second:
ex. output: [0,1,2]...[1,2,3,4,5]...[3,4,5,6,7]
*/
const example = source.pipe(bufferTime(2000, 1000));
//Print values to console
const subscribe = example.subscribe(val =>
console.log('Start Buffer Every 1s:', val)
);
Additional Resources
- bufferTime - Official docs
Source Code: https://github.com/ReactiveX/rxjs/blob/master/src/internal/operators/bufferTime.ts