停止子导航角度路由器

const routes: Routes = [    
  {
      path: 'parent/:id',
      component: ParentComponent,
      children: [
          {
              path: 'child',
              component: ChildComponent
          }
      ]
  }
];

class ParentComponent implements OnInit {
  readonly NUMBER_REGEX = /^\+?\d+$/;
  ngOnInit() {
    this.route.params.subscribe( params => {
      if (params.id) {
          if (!this.NUMBER_REGEX.test(params.id)) {
              this.router.navigateByUrl('/not-found');              
          }
      }   
    });
  }
}

class ChildComponent implements OnInit {
  ngOnInit() {
    console.log('don\'t want this to work on /parent/string/child but still works');
  }
}