在StackBlitz里創(chuàng)建一個rxjs項目，源代碼如下：

import { Observable, of } from "rxjs"; import { map } from "rxjs/operators"; import { interval } from "rxjs"; import { switchMap } from "rxjs/operators";const pollTasks = () => {return interval(1000).pipe(switchMap(counter => {return of(counter + 100);}),map(res => res + res)); };// caller can do subscription and store it as a handle: let tasksSubscription = pollTasks().subscribe(data =>console.log("timestamp: " + new Date() + ": " + data) ); // turn it off at a later timesetTimeout(() => tasksSubscription.unsubscribe(), 10000);

十秒之后自動關(guān)閉：

首先用rxjs interval創(chuàng)建一個Observable對象，每隔1秒鐘產(chǎn)生一個遞增的整數(shù)：

interval(1000)返回的Observable調(diào)用pipe進(jìn)行下一步處理：switchMap.

注意該switchMap的類型，接受一個輸入?yún)?shù)，project函數(shù)。該project函數(shù)的輸入是：value: number, index: number, 必須返回Observable. 整個project的函數(shù)類型是OperatorFunction<number, number>.

下面這個例子更加能夠說明問題：

import { Observable, of, OperatorFunction } from "rxjs"; import { map } from "rxjs/operators"; import { interval } from "rxjs"; import { switchMap } from "rxjs/operators";const add1Fn = value => value + 1; const add1OP: OperatorFunction<number, number> = map(add1Fn);const pollTasks = () => {return interval(1000).pipe(switchMap(counter => {return of(counter + 100);}),map(res => res + res),add1OP); };// caller can do subscription and store it as a handle: let tasksSubscription = pollTasks().subscribe(data =>console.log("timestamp: " + new Date() + ": " + data) ); // turn it off at a later timesetTimeout(() => tasksSubscription.unsubscribe(), 3000);

將函數(shù)傳入rxjs的operator，返回的是一個operatorFunction，將這個operatorFunction傳入pipe，返回的是新的Observable.

更多Jerry的原創(chuàng)文章，盡在：“汪子熙”:

總結(jié)

以上是生活随笔為你收集整理的rxjs的一个例子：什么是rxjs的OperatorFunction？的全部內(nèi)容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網(wǎng)站內(nèi)容還不錯，歡迎將生活随笔推薦給好友。