如何在angular4中将值从内容传递到侧边栏？

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

@Injectable()
export class DataSharingService {
  private data: any;

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

  getData() {
    return this.data;
  }
}

import { Component } from '@angular/core';
import { DataSharingService } from '路径/DataSharingService';

@Component({
  selector: 'app-content',
  template: `
    <button (click)="passValueToSidebar()">传递值到侧边栏</button>
  `
})
export class ContentComponent {
  constructor(private dataSharingService: DataSharingService) {}

  passValueToSidebar() {
    const value = '传递的值';
    this.dataSharingService.setData(value);
  }
}

import { Component } from '@angular/core';
import { DataSharingService } from '路径/DataSharingService';

@Component({
  selector: 'app-sidebar',
  template: `
    <div>{{ value }}</div>
  `
})
export class SidebarComponent {
  value: any;

  constructor(private dataSharingService: DataSharingService) {}

  ngOnInit() {
    this.value = this.dataSharingService.getData();
  }
}