Typescript rxjs Observable 数组连接 [英] Typescript rxjs Observable array concat

问题描述

我在使用带有打字稿的 rxjs Observable.concat 函数时遇到问题.收到错误无法读取未定义的属性‘应用’"

I am having trouble using rxjs Observable.concat function with typescript. Getting an error "Cannot read property 'apply' of undefined"

问题似乎只出现在打字稿和可能特定于 rxjs 版本 5 concat.该代码似乎适用于 rxjs V4.

The problem seems to be only within typescript and may be specific to rxjs version 5 concat. The code seems to work with rxjs V4.

这是说明问题的代码的简化版本...

Here is a simplified version of the code illustrating the problem...

 /*jshint esnext: true */

console.clear();
console.log('started');
class test{
    observableArray: Observable<any>[]=[];

    constructor(){
        this.observableArray.push(Rx.Observable.return("Line 1"));
        this.observableArray.push(Rx.Observable.return(56));
        this.observableArray.push(Rx.Observable.create((observer)=>{
             setTimeout(()=>{
                try{
                    observer.onNext("Waited for");
                    observer.onCompleted();
                }
                catch(err){
                     observer.onError(err);
                }
             },3000);
         }));
      }

    run(){
         // ... indeterminate number of observables pushed into array.
         // The problem lies below
         var source = Rx.Observable.concat(...this.observableArray);
         // seems to transpile into js: source =   Observable_1.Observable.concat.apply(Observable_1.Observable, this.observableArray);
         // In the chrome debugger I am getting error: Cannot read property 'apply' of undefined      

         var subscription = source.subscribe(
             function (x) {
                 console.log('Next: ' + x);
             },
             function (err) {
                 console.error('Error: ' + err);
             },
             function () {
                 console.log('Completed');
         });
      }
  }

}

这是jsbin:https://jsbin.com/naxeba/edit?html,js,console,output

推荐答案

好的，问题解决了.

Reactive js 版本 5 用户的重要说明:在使用 rxjs 的打字稿中，为了最小化应用程序的大小，必须专门为要包含的函数/运算符导入每个运算符.所以这条线...

Important note for users of reactive js version 5: In typescript with rxjs, to minimize app size each operator must be specifically imported for the function/operator to be included. So the line...

import {concat} from 'rxjs/operators/concat' 必须包含在打字稿文件的顶部才能使 concat 工作.

import {concat} from 'rxjs/operators/concat' must be inlcuded at the top of the typescript file for concat to work.

令我困惑的是，我在 VS2015 中获得了 Observable.concat 函数的智能感知，即使该函数实际上并未被导入.

What confused me was that I was getting intellisense in VS2015 for the Observable.concat function even though the function had not actually been imported.

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