如何在 Angular 7 中提取 JSON 数据并加载到数组中 [英] How to extract JSON Data and load into an Array in Angular 7

问题描述

我有一个包含一些数据的本地 JSON 文件.我只想从中提取 CityCodes 并存储在一个数组中.然后我想将 CityCodes 发送到 OpenWeatherMap API 请求.最后想在 HTML 文件中显示所有天气记录.

I have a local JSON File with some data. I want to extract only the CityCodes from it and store in an Array. Then i want to send the CityCodes to the OpenWeatherMap API Request. Finally want to Display all the Weather Records in the HTML file.

城市数据.json:

{
    "List": [
    {
    "CityCode": "1248991",
    "CityName": "Colombo",
    "Temp": "33.0",
    "Status": "Clouds"
    },
    {
    "CityCode": "1850147",
    "CityName": "Tokyo",
    "Temp": "8.6",
    "Status": "Clear"
    },
    {
    "CityCode": "2644210",
    "CityName": "Liverpool",
    "Temp": "16.5",
    "Status": "Rain"
    }
]

天气.Service.ts:

Weather.Service.ts :

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

@Injectable({
  providedIn: 'root'
})
export class WeatherService {

  apiKey = '9402da6bd74c395f71604c624cc2b231';
  url;

  constructor(private http:HttpClient) { 
    this.url='http://api.openweathermap.org/data/2.5/group?id=';  //API GET URL

  }

  getWeather(cityCode){
    return this.http.get(this.url+cityCode+'&units=metric&appid='+this.apiKey);
  }

}

home.component.ts :

home.component.ts :

这里我手动传递区号.而不是我需要在这里发送 JSON 形式的区号.

here i am passing the area code manually. Instead of that i need to send the area codes form JSON here.

import { Component, OnInit } from '@angular/core';
import { WeatherService } from "../shared/weather.service";
// import { weather} from "../shared/weather.model";

@Component({
  selector: 'app-home',
  templateUrl: './home.component.html',
  styleUrls: ['./home.component.css']
})
export class HomeComponent implements OnInit {

  location={    
    code: '1248991'  //Passing Area Code Manually
  };

  public weather: any;

  constructor(private weatherService:WeatherService) {

  }

  ngOnInit() {
    this.weatherService.getWeather(this.location.code).subscribe((Response:any)=>{
      console.log(Response);
      this.weather = Response.list;
    })
  }

}

home.component.html :

home.component.html :

<table class="table table-hover">
          <thead>
            <th>City</th>
            <th>City Code</th>
            <th>Temperature</th>
            <th>Description</th>            
          </thead>
          <tbody>
            <tr *ngFor="let weather of weather">
              <td>{{weather.name}}</td>
              <td>{{weather.id}}</td>
              <td>{{weather.main.temp}}</td>
              <td>{{weather.weather[0].description}}</td>              
            </tr>
          </tbody>
        </table>

推荐答案

我通过将 JSON 响应推送到数组中解决了这个问题.

I Solved it by pushing the JSON Response into an Array.

Home.component.ts

  public data: any;
  public weather: any;

  constructor(private weatherService:WeatherService) {

  }

  ngOnInit() {   
    this.weatherService.getJsonData('./assets/City.json').subscribe(data => {
            this.data = data;         //Reading JSON Data
            this.getWeatherList();    //Calling GetWeatherList Function
      }); 
  }

  getWeatherList(){
    if (this.data) {

      // console.log(this.data);

      const dataList = this.data.List;
      let tempArr : any = [];

      for (let temp of dataList) {
        this.weatherService.getWeather(temp.CityCode).subscribe((Response: any) => {
          tempArr.push(Response.list[0]);         //Pushing Response to Array
        })        
      }
      console.log(tempArr)
      this.weather = tempArr;   //Assigning Array to Weather Constant
    }
  }

这篇关于如何在 Angular 7 中提取 JSON 数据并加载到数组中的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！