ng g service my-new-service

创建到指定目录下面

ng g service services/storage

1.app.module.ts 里面引入创建的服务

import { StorageService} './services/storage.service';

2. NgModule 里面的 providers 里面依赖注入服务

NgModule({ declarations: [
    AppComponent,
    HeaderComponent,
    FooterComponent,
    NewsComponent,
    TodolistComponent

], imports: [

    BrowserModule,

FormsModule

  ],
  providers: [StorageService],
  bootstrap: [AppComponent]

})
export class AppModule { }

 

使用的页面引入服务,注册服务
import { StorageService } from '../../services/storage.service';
constructor(private storage: StorageService) {
}

使用:
  
addData(){ 

this.list.push(this.username); this.storage.set('todolist',this.list);

  }
removerData(key){

console.log(key); this.list.splice(key,1); this.storage.set('todolist',this.list);

}