swift - RxSwift - 处理订阅是否会导致底层序列发出 onComplete？

Question

我正在阅读 Packt ( https://www.oreilly.com/library/view/reactive-programming-with/9781787120211/) 撰写的关于 RxSwift 的书“使用 Swift 4 进行响应式编程”。在一节中，这本书说:

"Disposing of a subscription will cause the underlying Observable sequence to emit a completed event and terminate"

但是我发现这个短语是不正确的。这是一个例子:

        let publisher = PublishSubject<Int>() //Create an <Int> sequence
        let subscription1 = publisher.asObservable() //Create 1st subscription
            .debug("Subscription 1")
            .subscribe { (event) in
            print(event)
        }
        let subscription2 = publisher.asObservable() //Create 2nd subscription
            .debug("Subscription 2")
            .subscribe { (event) in
                print(event)
        }
        publisher.onNext(1) //Emit first event
        subscription1.dispose() //Dispose the 1st subscription. According to the phrase above, publisher should emit an onComplete event
        publisher.onNext(2) //Emit second event

正如我在代码中的评论所说，在 subscription1.dispose() 处，publisher 应该发出 onComplete 事件，但实际上它仍然可以发出新事件像往常一样，因此输出:

2018-11-01 19:43:59.796: Subscription 1 -> subscribed
2018-11-01 19:43:59.798: Subscription 2 -> subscribed
2018-11-01 19:43:59.798: Subscription 1 -> Event next(1)
next(1)
2018-11-01 19:43:59.798: Subscription 2 -> Event next(1)
next(1)
2018-11-01 19:43:59.799: Subscription 1 -> isDisposed
2018-11-01 19:43:59.799: Subscription 2 -> Event next(2)
next(2)

谁能证实我的理解是正确的？还是我错过了 RxSwift 幕后的任何东西？

提前致谢

Answer 1

您对取消订阅的理解是正确的:处理订阅不会导致 onComplete 运行。但是，当达到 onComplete 或 onError 时，它将自动取消订阅(http://reactivex.io/documentation/contract.html 订阅和取消订阅部分非常有用)