ionic3自定义服务

1、创建项目:ionic start demo tabs;
2、创建一个服务：ionic g provider data-server，可以做一个保存本地存储的服务用来各个页面调用,部分截图如下：

3、在app.module.ts中引入服务:
app.module.ts:

import { NgModule, ErrorHandler } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { IonicApp, IonicModule, IonicErrorHandler } from 'ionic-angular';
import { MyApp } from './app.component';

import { AboutPage } from '../pages/about/about';
import { ContactPage } from '../pages/contact/contact';
import { HomePage } from '../pages/home/home';
import { TabsPage } from '../pages/tabs/tabs';

import { Test1Page } from '../pages/test1/test1';

import { StatusBar } from '@ionic-native/status-bar';
import { SplashScreen } from '@ionic-native/splash-screen';

import { DataServerProvider } from '../providers/data-server/data-server'; //自定义服务

@NgModule({
  declarations: [
    MyApp,
    AboutPage,
    ContactPage,
    HomePage,
    TabsPage,
    Test1Page,
  ],
  imports: [
    BrowserModule,
    IonicModule.forRoot(MyApp)
  ],
  bootstrap: [IonicApp],
  entryComponents: [
    MyApp,
    AboutPage,
    ContactPage,
    HomePage,
    TabsPage,
    Test1Page,
  ],
  providers: [
    StatusBar,
    SplashScreen,
    {provide: ErrorHandler, useClass: IonicErrorHandler},
    DataServerProvider, //自定义的服务
  ]
})
export class AppModule {}

自定义组件、自定义指令、自定义管道都是在imports中引入的，而自定义服务是在providers中引入的

providers/data-server/data-server.ts：

import { Injectable } from '@angular/core';
import { stringify } from '@angular/core/src/util';

@Injectable()
export class DataServerProvider {

  constructor() {
    console.log('Hello DataServerProvider Provider');
  }
  public setLocalstorage(key, value){
    localStorage.setItem(key, JSON.stringify(value));
  }
  public getLocalstoragfe(key){
    return JSON.parse(localStorage.getItem(key))
  }
  public removeLocalstorage(key){
    localStorage.remove(key);
  }
  public clearLocalstorage(){
    localStorage.clear();
  }
}

选择在about页面中试用:

about.html:

  
    
      About
    
  



  

    保存本地存储
    获取本地存储
    清除本地存储
  

about.ts：

import { Component } from '@angular/core';
import { NavController } from 'ionic-angular';
import { DataServerProvider } from '../../providers/data-server/data-server';

@Component({
  selector: 'page-about',
  templateUrl: 'about.html'
})
export class AboutPage {
  constructor(public navCtrl: NavController, public data: DataServerProvider) {

  }
  ngOnInit(){
  }
  sayLocalStorage(){
    console.log(this.data.getLocalstoragfe('key'));
  }
  clearLocalStorage(){
    this.data.clearLocalstorage();
  }
  saveLocalStorage(){
    this.data.setLocalstorage('key', {item1: 1, item2: 2})
  }
}

ionic serve重启服务后，先点击保存再点击查看就能看到保存的本地存储，点击清除再点击查看就发现返回null：