Unit testing 角度2可观测服务Karma Jasmine单元测试不工作

我是Angular 2和Karma+Jasmine单元测试的新手。为了让这个单元测试使用模拟响应，我无法找出我犯了什么语义错误。在控制台中，当运行“expect（items[0].itemId）.toBe（2）；”时，会显示items[0].itemId未定义

有没有人能帮我走出困境或者给我指出正确的方向？如果您需要任何其他信息，请告诉我。谢谢

项目1.ts

export class Item {
     itemId: number;
     itemName: string;
     itemDescription: string;
}

item.service.ts

import { Injectable, Inject } from '@angular/core';
    import { Headers, Http } from '@angular/http';
    import { Observable } from 'rxjs/Rx';
    import { Item } from './item';
@Injectable()
export class ItemService {
    private headers = new Headers({'Content-Type': 'application/json'});

    constructor(
    private http: Http)
    {

    }

    getItems(listOptions: Object): Observable<Item[]> {
    return this.http.post('/listItems', listOptions, {headers:this.headers})
       .map(response => response.json() as Item[])
  }
}

普朗克：

---

（Plunkr也有一些错误，我需要帮助，但主文件在那里）

mockResponse主体与实际响应主体不匹配，这就是我收到错误的原因

---

mockResponse=newresponse（newresponseOptions（{body:{data:items}，status:200}））应该是
mockResponse=newresponse（newresponseOptions（{body:items，status:200}））
response.json（）
不是项的数组，
response.json（）.data
是。@jornsharpe谢谢！我收到一个错误，该错误表示类型“Item[]”上不存在属性“data”

是，因为您对参数使用了错误的类型。@jonrsharpe您能告诉我应该使用哪种类型吗？反映您发送的实际对象的类型吗？在本例中，一个名为

data

的字段包含项数组。如果这与实际有效载荷不同，请修复测试以反映真实结构。

import { TestBed, fakeAsync, inject, tick } from '@angular/core/testing';
import { MockBackend } from '@angular/http/testing';
import { Http, BaseRequestOptions, Response, ResponseOptions } from '@angular/http';
import { Observable } from 'rxjs/Rx';
import { ItemService } from './item.service';
import { Item } from './item';


describe('ItemService', () => {
  let mockResponse, matchingItem, connection;

  beforeEach(() => {
    TestBed.configureTestingModule({
      providers: [
        ItemService,
        MockBackend,
        BaseRequestOptions,
        {
          provide: Http,
          useFactory: (backend, defaultOptions) => new Http(backend, defaultOptions),
          deps: [MockBackend, BaseRequestOptions]
        },
        // { provide: XHRBackend, useClass: MockBackend }        
      ]
    });

    const items = [
      {
        "itemId":2,
        "itemName":"test item1",
        "itemDescription":"hello hello"        
      },
      {
        "itemId":1,
        "itemName":"name2124111121",
        "itemDescription":"description212412112"        
      }
    ];
    mockResponse = new Response(new ResponseOptions({body: {data: items}, status: 200}));
  });

  describe('getItems', () => {

    //Subscribing to the connection and storing it for later
    it('should return all the items',inject([ItemService, MockBackend], (service: ItemService, backend: MockBackend) => {

        backend.connections.subscribe(connection => {
          connection.mockRespond(mockResponse);
        });
        service.getItems({isActive: true, sortColumn: "lastModifiedDateUtc", sortOrder: "desc"})
        .subscribe((items: Item[]) => {
          expect(items.length).toBe(2);
        });
      }));
    });
  });