如何知道用户是否在Angular中屏蔽了自己的PWA通知

import { Component } from '@angular/core';
import { SwUpdate } from '@angular/service-worker';

@Component({
  selector: 'app-root',
  template: `
    <button (click)="checkNotificationPermission()">Check Notification Permission</button>
  `,
})
export class AppComponent {
  constructor(private swUpdate: SwUpdate) {}

  checkNotificationPermission() {
    if (this.swUpdate.isEnabled) {
      Notification.requestPermission().then((permission) => {
        if (permission === 'denied') {
          console.log('User has blocked PWA notifications.');
        } else if (permission === 'granted') {
          console.log('User has allowed PWA notifications.');
        }
      });
    } else {
      console.log('Service Worker is not enabled.');
    }
  }
}