如何让Angular 2记住滚动位置？

import { Component, HostListener } from '@angular/core';
import { Router, NavigationEnd } from '@angular/router';

export class YourComponent {
  scrollPosition = 0;
  // ...
}

export class YourComponent {
  // ...

  @HostListener('window:scroll', ['$event'])
  onScroll(event: any) {
    this.scrollPosition = window.pageYOffset;
  }

  @HostListener('window:unload', ['$event'])
  onUnload(event: any) {
    localStorage.setItem('scrollPosition', this.scrollPosition.toString());
  }

  // ...
}

export class YourComponent implements OnInit {
  // ...

  ngOnInit() {
    const savedScrollPosition = localStorage.getItem('scrollPosition');
    if (savedScrollPosition) {
      window.scrollTo(0, parseInt(savedScrollPosition, 10));
    }
  }

  // ...
}