Branch out the source Observable values as a nested Observable with each
nested Observable emitting at most windowSize values.
windowCount<T>(windowSize: number, startWindowEvery: number = 0): OperatorFunction<T, Observable<T>>
Parameters
| windowSize |
The maximum number of values emitted by each
window.
|
| startWindowEvery |
Optional. Default is 0.
Interval at which to start a new window.
For example if startWindowEvery is 2, then a new window will be started
on every other value from the source. A new window is started at the
beginning of the source by default.
|
Returns
OperatorFunction<T, Observable<T>>: An Observable of windows, which in turn
are Observable of values.
Description
It's like bufferCount, but emits a nested
Observable instead of an array.
Returns an Observable that emits windows of items it collects from the source
Observable. The output Observable emits windows every startWindowEvery
items, each containing no more than windowSize items. When the source
Observable completes or encounters an error, the output Observable emits
the current window and propagates the notification from the source
Observable. If startWindowEvery is not provided, then new windows are
started immediately at the start of the source and when each window completes
with size windowSize.
Examples
Ignore every 3rd click event, starting from the first one
import { fromEvent } from 'rxjs';
import { windowCount, map, mergeAll } from 'rxjs/operators';
const clicks = fromEvent(document, 'click');
const result = clicks.pipe(
windowCount(3)),
map(win => win.skip(1)), // skip first of every 3 clicks
mergeAll(), // flatten the Observable-of-Observables
);
result.subscribe(x => console.log(x));
Ignore every 3rd click event, starting from the third one
import { fromEvent } from 'rxjs';
import { windowCount, mergeAll } from 'rxjs/operators';
const clicks = fromEvent(document, 'click');
const result = clicks.pipe(
windowCount(2, 3),
mergeAll(), // flatten the Observable-of-Observables
);
result.subscribe(x => console.log(x));