windowwhen.md

windowWhen

signature: windowWhen(closingSelector: function(): Observable): Observable

Close window at provided time frame emitting observable of collected values from source.

Examples

Example 1: Open and close window at interval

( jsBin | jsFiddle )

//emit immediately then every 1s
const source = Rx.Observable.timer(0,1000);
const example = source
    //close window every 5s and emit observable of collected values from source
    .windowWhen((val) => Rx.Observable.interval(5000))
    .do(() => console.log('NEW WINDOW!'))

const subscribeTwo = example 
  //window emits nested observable
  .mergeAll()
/*
  output:
  "NEW WINDOW!"
  0
  1
  2
  3
  4
  "NEW WINDOW!"
  5
  6
  7
  8
  9
*/
  .subscribe(val => console.log(val));

Additional Resources

• windowWhen 📰 - Official docs

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📁 Source Code: https://github.com/ReactiveX/rxjs/blob/master/src/operator/windowWhen.ts