Angular 5、rxjs映射到json，'json'类型上不存在对象

Question

尝试关注在线视频，然后出现这个，我是新手 angular，其他解决方案对我没有帮助。

import { HttpClient } from '@angular/common/http';
import { Injectable } from '@angular/core';
import 'rxjs/add/operator/map';

/*
  Generated class for the WeatherProvider provider.

  See https://angular.io/guide/dependency-injection for more info on providers
  and Angular DI.
*/
@Injectable()
export class WeatherProvider {
  apikey='7d2dc7a226a78c14';
  url;

  constructor(public http: HttpClient) {
    console.log('Hello WeatherProvider Provider');
    this.url='http://api.wunderground.com/api/'+this.apikey+'/conditions/q'
  }

    getWeather(city,state){
      return this.http.get(this.url+'/'+state+'/'+city+'.json')
        .map(res => res.json() );      
    }
}

Answer 1

使用 angular 5 和 httpClient，您不再需要使用地图部分。

在此处阅读更多内容：https://angular.io/guide/http#type-checking-the-response

getWeather(city,state){
  return this.http.get(this.url+'/'+state+'/'+city+'.json');     
}

如果你想获取特定格式的数据，你可以告诉 HttpClient 响应的类型，使输出的消费更容易和更明显。

export interface Config {
 heroesUrl: string;
 textfile: string;
}

然后：

getConfig() {
  // now returns an Observable of Config
  return this.http.get<Config>(this.configUrl);
}

Answer 2

如果您使用的是新的 HttpClient，则无需解析 JSON，因为它会自动为您解码：

https://angular.io/guide/http#type-checking-the-response

The HttpClient.get() method parsed the JSON server response into the anonymous Object type. It doesn't know what the shape of that object is.

还有https://angular.io/guide/http#requesting-non-json-data.

Angular 5、rxjs映射到json，'json'类型上不存在对象

Angular 5, rxjs map to json, 'json' does not exist on the the type 'object

json

rxjs

ionic-framework

rxjs5

angular