在 Rx.observable 上找不到采摘

Question

我正在尝试 https://github.com/Reactive-Extensions/RxJS 尝试运行通过他们使用 Typescript 和 Angular 的示例 2. 当我编译代码时它抱怨 "Property 'pluck' does not exist on type 'Observable<{}>'"。我不明白为什么 pluck 不可用。它是否已从 rxjs 5 中删除？

使用：

angular 2.0.0-beta.0 rxjs 5.0.0-beta.0

代码：

import {Component} from 'angular2/core';
import {FORM_DIRECTIVES} from 'angular2/common';
import {Http} from 'angular2/http';
import {Observable} from 'rxjs/Observable';

import {Title} from '../providers/title';

@Component({
  selector: 'home',
  directives: [...FORM_DIRECTIVES],
  providers: [Title],
  pipes: [],
  styles: [require('./home.css')],
  template: require('./home.html')
})
export class Home {
  wikisearch: any = {};

  // TypeScript public modifiers
  constructor(public title: Title, public http: Http) {
    var input = document.getElementById('wikisearch');

    /* Only get the value from each key up */
    var keyups = Observable.fromEvent(input, 'keyup')
      .pluck('target', 'value')
      .filter((text) => text.length > 2);
  }
}

Answer 1

Angular 2 使用 RxJS 5（https://github.com/ReactiveX/RxJS), which is a complete rewrite of the current version (https://github.com/Reactive-Extensions/RxJS). RxJS 5 is still in beta. Some operators from RxJS 4 are not yet available in RxJS 5. This is the case for pluck. I recommend you take a look at RxJS 5 documentation and also the migration guide 因为这两个版本之间存在一些 API 差异。

对于此特定示例，您可以使用 map 轻松替换 pluck 运算符：

var keyups = Observable.fromEvent(input, 'keyup')
    .map((target) => target.value)
    .filter((text) => text.length > 2);

更新： pluck 是 now available in RxJS 5 since version 5.0.0-beta.1.

在 Rx.observable 上找不到采摘

pluck not found on Rx.observable

rxjs

typescript

angular