Angular6如何将共享数据与服务的同级绑定，使每个实例都有各自的引用

ng generate service shared-data

import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class SharedDataService {
  sharedData: any;

  constructor() { }

  setData(data: any) {
    this.sharedData = data;
  }

  getData() {
    return this.sharedData;
  }
}

import { Component, OnInit } from '@angular/core';
import { SharedDataService } from '../shared-data.service';

@Component({
  selector: 'app-example',
  template: `
    <div>
      Shared Data: {{ sharedData }}
    </div>
    <button (click)="updateData()">Update Data</button>
  `
})
export class ExampleComponent implements OnInit {
  sharedData: any;

  constructor(private sharedDataService: SharedDataService) { }

  ngOnInit() {
    this.sharedData = this.sharedDataService.getData();
  }

  updateData() {
    this.sharedDataService.setData('New Data');
  }
}