Question

我刚刚掌握了Promise，现在我正在学习Observables！唉！

尝试使用Angular 4进行简单的get请求。轻松地遵循本教程：https://scotch.io/tutorials/angular-2-http-requests-with-observables。

最初，当我尝试从Observable导入rxjs/Observable时，我收到了一个编译错误，主要是说map不是Observable<Response>的函数，而是将导入更改为rxjs解决了编译错误。但是现在我在运行时遇到了同样的错误......

我如何处理以下回复有什么问题？

import { Injectable } from '@angular/core';
import { apiConfig } from '../../environments/environment';
import { Http, Response, Headers, RequestOptions } from '@angular/http';
import { APIRequest, APIResponse} from './api-objects';
import { Observable } from 'rxjs';

/**
 * The BaseAPIService can be extended to provide base functionality for communicating to the API endpoint.
 */
@Injectable()
export class BaseAPIService {

  private apiBase = apiConfig.base;

  constructor(protected http: Http) { }

  /**
   * Sends an API request to the endpoint
   */
  sendRequest(request: APIRequest): Observable<APIResponse> {
    const options = new RequestOptions({ });
    const fullUrl = `apiBase${request.url}`;
    request.body = request.body || {};
    return this.http.get(fullUrl).map((response: Response) => new APIResponse(response));
  }
}

**错误详情**

this.http.get(...).map is not a function
    at CoreAPIService.webpackJsonp.356.BaseAPIService.sendRequest (base-api.service.ts:25)

Answer 1

您还需要导入您计划使用的任何RxJS运算符。您可以在模块级别执行此操作。

示例：

import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';
import 'rxjs/add/operator/switchMap';

如何使用observables在angular 2 http服务中进行http get请求

1 个答案: