Title of routing page using angular

component.ts

 this._router.events.pipe(
      filter((event) => event instanceof NavigationEnd)
      , map(() => this.activatedRoute)
      , map((route) => {
        while (route.firstChild) route = route.firstChild;
        return route;
      })).pipe(
        filter((route) => route.outlet === 'primary')
        , mergeMap((route) => route.data))
      .subscribe((event) => this.title = event.title);

router.ts

const routes: Routes = [{
  path: 'calendar',
  component: CalendarComponent,
  children: [
    { path: '', redirectTo: 'new', pathMatch: 'full' },
    { path: 'all', component: CalendarListComponent, data: { title: 'My Calendar' } },
    { path: 'new', component: CalendarEventComponent, data: { title: 'New Calendar Entry' } },
    { path: ':id', component: CalendarEventComponent, data: { title: 'Calendar Entry' } }
  ]
}];