Ionic 2:存储来自 http GET 请求的响应

Question

我正在开发一个应用程序并设置了一个事件提供程序。我正在使用 Eventbrite API 来获取城市中发生的事件池。 我在尝试弄清楚如何执行 get 请求并将其存储在变量中时遇到了困难。以下是请求的 URL：

https://www.eventbriteapi.com/v3/events/search/?location.address=Atlanta&expand=organizer,venue&token={MY_TOKEN}

这是我到目前为止的提供者：

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';
import {NativeStorage} from "ionic-native";
import 'rxjs/add/operator/map';
/*
  Generated class for the EventProvider provider.
  See https://angular.io/docs/ts/latest/guide/dependency-injection.html
  for more info on providers and Angular 2 DI.
*/
@Injectable()
export class EventProvider {
  data:any;
  constructor(public http: Http) {
    this.data = null;
    //console.log('Hello EventProvider Provider');
  }
  public getCityEvents(city) {
    var event = {id: "", name: "", start: "", end: "", latitude: "", longitude: "", venue:""};
    NativeStorage.getItem('event')
      .then(function (data) {
        alert("data: " + JSON.stringify(data));
        alert("data id: " + data.id);
        event = {
          id = data.id,
          name = data.name,
          start = data.start,
          end = data.end,
          latitude = data.latitude,
          longitude = data.longitude,
          venue = data.venue
        };

      this.http.get("https://www.eventbriteapi.com/v3/events/search/?location.address=Atlanta&expand=organizer,venue&token=VMGQGYQUIO3IKNS75BD4").subscribe( data =>{
        console.log(data);
        },
      error => {
        console.log(error)
      });
      })
  }
}

我现在只想将来自此 get 请求的 JSON 响应存储在变量中。有人可以提供一些帮助吗？

Answer 1

在NativeStorage.getItem('event').then((data) => { ... }中使用箭头函数，您可以在http回调中访问实际的上下文this。

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';
import {NativeStorage} from "ionic-native";
import 'rxjs/add/operator/map';
/*
  Generated class for the EventProvider provider.
  See https://angular.io/docs/ts/latest/guide/dependency-injection.html
  for more info on providers and Angular 2 DI.
*/
@Injectable()
export class EventProvider {
  data:any;
  constructor(public http: Http) {
    this.data = null;
    //console.log('Hello EventProvider Provider');
  }
  public getCityEvents(city) {
    var event = {id: "", name: "", start: "", end: "", latitude: "", longitude: "", venue:""};
    NativeStorage.getItem('event')
      .then((data) => {
        alert("data: " + JSON.stringify(data));
        alert("data id: " + data.id);
        event = {
          id = data.id,
          name = data.name,
          start = data.start,
          end = data.end,
          latitude = data.latitude,
          longitude = data.longitude,
          venue = data.venue
        };

      this.http.get("https://www.eventbriteapi.com/v3/events/search/?location.address=Atlanta&expand=organizer,venue&token=VMGQGYQUIO3IKNS75BD4").subscribe( data =>{
        console.log(data);
        //variable assignment
        this.data = data;
      },
      error => {
        console.log(error)
      });
      })
  }

Answer 2

创建函数

  getData() {
return this.http.get("https://www.eventbriteapi.com/v3/events/search/?location.address=Atlanta&expand=organizer,venue&token=VMGQGYQUIO3IKNS75BD4")
                    .map(this.extractData)
                    .catch(this.handleError);
  }

  private extractData(res: Response) {
let body = res.json();
return body.data || { };
  }

然后订阅

  this.getData()
                     .subscribe(
                       data => console.log(data);
                       error =>  console.log(error));
  }

参考 角度文档 你从邮递员那里得到的作品。