为什么RxJS Observable构造函数中的代码不被调用？(Why is the code inside RxJS Observable constructor not being called?

为什么RxJS Observable构造函数中的代码不被调用？(Why is the code inside RxJS Observable constructor not being called?)

如果我在浏览器控制台中这样做，构造函数似乎不会被调用 -

Observable.create(observer => console.log('this is the observer'); //doesn't gets logged this.alertObserver = observer );

或这个 ：-

new Observable(observer => console.log('this is the observer'); //doesn't gets logged this.alertObserver = observer );

我试过通过导入Observer

import {Observable} from 'rxjs/Observable';

和

import {Observable} from 'rxjs/Rx';

但没有任何帮助。

任何建议？

If I do this in browser console, the constructor function doesnot seems to be called-

Observable.create(observer => console.log('this is the observer'); //doesn't gets logged this.alertObserver = observer );

or this :-

new Observable(observer => console.log('this is the observer'); //doesn't gets logged this.alertObserver = observer );

I have tried importing Observer through

import {Observable} from 'rxjs/Observable';

and

import {Observable} from 'rxjs/Rx';

but with no help.

Any suggestion ?

最满意答案

Rx observables是延迟加载的。 你至少需要一个用户。

尝试：

var observable = Observable.create(observer => console.log('this is the observer'); this.alertObserver = observer ); observable.subscribe();

Rx observables are lazy loaded. You need at least one subscriber.

Try:

var observable = Observable.create(observer => console.log('this is the observer'); this.alertObserver = observer ); observable.subscribe();