angular 服务

1. 创建 ng g s service/list

2.在app.module.ts中引入

import { ListService } from './service/list.service';
@NgModule({
　　...
　　providers: [ListService],
})

import { ListService } from 'src/app/service/list.service';


 list:Array<string> = [];

  constructor(private listService:ListService=new ListService() ) { }


  ngOnInit(): void {
    this.list = this.listService.getList();
  }

  clickHandle(){
    this.listService.addList('node.js')
  
  }