如何使用 Angular 9 中的参数测试 http.post 请求？

我是角度新手 我有一个使用一些参数调用 HTTP post 请求的服务。 现在我想以角度测试该服务功能。

我的服务部分是

import { HttpClient, HttpHeaders } from '@angular/common/http';
import { Injectable } from '@angular/core';

@Injectable({
providedIn: 'root'
})
export class GetProviderService{
      providersData: any;
      constructor(private http: HttpClient) {
       }

getProviders(param: any): any{
   var json = JSON.stringify(param);
const myHeader = new HttpHeaders().set('content-type','application/json');
this.http.post<any>(url, json, {headers: myHeader}).subsribe(data=> {
   this.providerData = data;
   return this.providerData;
   }),
   (erorr) => {
     window.alert("error");
     return null;
   }
}

现在我想介绍带有错误订阅和错误的 getProviders 函数。 我怎样才能做到这一点？

先感谢您。

假设您从某处获取网址（例如：getProviders(param: any, url: string)是一个测试套件的示例：

import { TestBed  } from '@angular/core/testing';
import { HttpClientTestingModule, HttpTestingController  } from '@angular/common/http/testing';
import { GetProviderService } from './get-provider.service';

describe('GetProviderService', () => {
  let service: GetProviderService;
  let httpMock: HttpTestingController;

  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [
        HttpClientTestingModule
      ]
    });
    service = TestBed.inject(GetProviderService);
    httpMock = TestBed.inject(HttpTestingController);
  });

  fit('should log success on success', () => {
    const mockUrl = 'http://mockurl.com/test';
    const mockResponse = {hello: 'test'}
    service.getProviders({}, mockUrl);
    httpMock.expectOne(mockUrl).flush(mockResponse);
    // your expects here
  });

  fit('should log error on error', () => {
    const mockUrl = 'http://mockurl.com/test';
    const mockErrorMsg = 'My mock error message'
    const mockError = new ErrorEvent('Network error', {
      message: mockErrorMsg,
    });
    service.getProviders({}, mockUrl);
    httpMock.expectOne(mockUrl).error(mockError);
    // your expects here
  });
});

这是相关的角度文档：https://angular.io/guide/http#testing-http-requests https://angular.io/guide/http#testing-http-requests

它是 http 指南的一部分，而不是测试指南的一部分，可能这就是您没有找到它的原因。