ionic3+Angular4实现接口请求及本地json文件读取示例

2019-11-19 15:11:30

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一准备工作

首先，ionic3+Angular4的开发环境你得有，这里就不赘述。环境准备好，创建一个空白项目，模板自选。

二实现过程

1 新建json文件和service

service记得在app.module.ts中引用

json和service

2 json文件格式

格式类似这样，根据实际需求决定。

[ {  "id":"1",  "name":"xiehan",  "age":"24",  "message":"测试json文件读取" }, {  "id":"2",  "name":"xiehan",  "age":"24",  "message":"测试json文件读取" }, {  "id":"3",  "name":"xiehan",  "age":"24",  "message":"测试json文件读取" }, {  "id":"4",  "name":"xiehan",  "age":"24",  "message":"测试json文件读取" }]

3 service

import {Injectable} from '@angular/core';import {Observable} from 'rxjs/Observable';import {Http, Response} from '@angular/http';import "rxjs/add/operator/map";@Injectable()export class DemoService { constructor(private httpService: Http){ } // 网络接口请求 getHomeInfo(): Observable<Response> {  return this.httpService.request('http://jsonplaceholder.typicode.com/users') } // 本地json文件请求 getRequestContact(){  return this.httpService.get("assets/json/message.json") }}

4 数据显示

1 网络接口请求

//home.tsimport {ChangeDetectorRef, Component} from '@angular/core';import { NavController } from 'ionic-angular';import {DemoService} from "../../services/demo.service";@Component({ selector: 'page-home', templateUrl: 'home.html'})export class HomePage { // 接收数据用 listData: Object; // 依赖注入 constructor(public navCtrl: NavController,       private ref: ChangeDetectorRef,       private demoService: DemoService,) { } ionViewDidLoad() {  // 网络请求  this.getHomeInfo(); } getHomeInfo(){  this.demoService.getHomeInfo()   .subscribe(res => {    this.listData = res.json();    // 数据格式请看log    console.log("listData------->",this.listData);    this.ref.detectChanges();   }, error => {    console.log(error);   }); }} //home.html<ion-header> <ion-navbar>  <ion-title>首页</ion-title> </ion-navbar></ion-header><ion-content padding> <ion-list *ngFor="let item of listData">  <ion-item>  <!--?是Angular特定语法，相当于判断数据是否存在，有则显示无则不显示-->   {{item?.name}}  </ion-item> </ion-list></ion-content>

效果图

2 本地json文件请求

service中已经写了getRequestContact()方法对本地json文件读取。

//contact.tsimport {ChangeDetectorRef, Component} from '@angular/core';import { NavController } from 'ionic-angular';import {DemoService} from "../../services/demo.service";@Component({ selector: 'page-contact', templateUrl: 'contact.html'})export class ContactPage { contactInfo=[]; constructor(public navCtrl: NavController,       private demoService: DemoService,       private ref: ChangeDetectorRef,) { } ionViewDidLoad() {  // 网络请求  this.getRequestContact(); } getRequestContact(){  this.demoService.getRequestContact()   .subscribe(res => {    this.contactInfo = res.json();    console.log("contactInfo------->",this.contactInfo);    this.ref.detectChanges();   }, error => {    console.log(error);   }); }}// contact.html<ion-header> <ion-navbar>  <ion-title>   联系人  </ion-title> </ion-navbar></ion-header><ion-content> <ion-list>  <ion-item *ngFor="let item of contactInfo">   <div style="display: flex;flex-direction: column;">    <span>姓名:{{item?.name}}</span>    <span>年龄:{{item?.age}}</span>    <span>信息:{{item?.message}}</span>   </div>  </ion-item> </ion-list></ion-content>

效果图