RxJS

概念

RxJS 使用的是观察者模式，用来编写异步队列和事件处理。

Observable

import { Observable } from "rxjs";

const observable = new Observable((subscribe) => {
  subscribe.next(1);
  subscribe.next(2);
  subscribe.next(3);

  setTimeout(() => {
    subscribe.next(4);

    subscribe.complete();
  }, 3000);
});

observable.subscribe({
  next: (num) => {
    console.log(num);
  },
  complete: () => {
    console.log("complete");
  },
});

// 输出 1 2 3 4 complete

interval

import { interval, take } from "rxjs";

interval(100)
  .pipe(take(5))
  .subscribe((e) => console.log(e));

// 输出 0 1 2 3 4

of

import { filter, map, of } from "rxjs";

of(1, 2, 3, 4, 5, 6)
  .pipe(
    map((v) => ({ num: v })),
    filter((v) => v.num % 2 == 0),
  )
  .subscribe((e) => {
    console.log(e);
  });