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[RxJS] Starting a Stream with SwitchMap & switchMapTo

From an event map to another event we can use switchMap(), switchMap() accept an function which return an obervable. The following code: When you click the button, it will start a interval to console out the count... const Observable = Rx.Observable;…

[RxJS] Toggle A Stream On And Off With RxJS

This lesson covers how to toggle an observable on and off from another observable by showing how to use a checkbox as a toggle for a stream of data. <!DOCTYPE html> <html> <head> <script src="https://npmcdn.com/@reactivex/rxjs@5.…

[RxJS] Stopping a Stream with TakeUntil

Observables often need to be stopped before they are completed. This lesson shows how to use takeUntil to stop a running timer. Then we use the starting stream and the stopping stream together to create a simple stopwatch. const Observable = Rx.Obser…

[RxJS] Logging a Stream with do()

To help understand your stream, you’ll almost always want to log out some the intermediate values to see how it has progressed during its lifespan. This lesson teaches you how to use do to log values in the middle of the stream without having an impa…

[RxJS] Completing a Stream with TakeWhile

Subscribe can take three params: subscribe( (x)=> console.log(x), err=> console.log(err), ()=> console.log('complete') ); If we want to stop the progame at some condition, so we need to notify complete function, which is the third param in subscr…

[RxJS] Implement RxJS `switchMap` by Canceling Inner Subscriptions as Values are Passed Through

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rxjs简单入门

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RxJS——Operators

RxJS 的操作符(operators)是最有用的,尽管 Observable 是最基本的.操作符最基本的部分(pieces)就是以申明的方式允许复杂的异步代码组合简化. 什么是操作符? 操作符是函数.这里有两种操作符: 管道操作符(Pipeable Operators)是可以通过使用 observableInstance.pipe(operator()) 管道传输到 Observable 对象.这些包括,filter(...),mergeMap(...).当调用他们时,它们不会改变已存在的 O…

angular7 Rxjs 异步请求

Promise 和 RxJS 处理异步对比 Promise 处理异步: let promise = new Promise(resolve => { setTimeout(() => { resolve('---promise timeout---'); }, 2000); }); promise.then(value => console.log(value)); RxJS 处理异步 import {Observable} from 'rxjs'; let stream = new O…