如何知道哪个observable触发器在Rx.Observable.combineLatest中发生了变化

Question

我可以使用Rx.Observable.combineLatest,这样我就会在任何可观察到的更改时通知更改.但我怎么知道哪些可观察到的变化呢？

var s1 = someObservable1();
var s2 = someObservable2();
Rx.Observable.combineLatest(s1, s2).subscribe(function(){
    // How to know which Observable triggers combineLatest change

});

Answer 1

RxJs无法实现这一目标.不过你可以用额外的状态来做:

var trigger = "";

Rx.Observable
  .combineLatest(
    s1.do(function() { trigger = "s1"; }),
    s2.do(function() { trigger = "s2"; }))
  .subscribe(function(){
    // use trigger
  });