Interface that a class can implement to be a guard deciding if a route can be deactivated. If all guards return true, navigation continues. If any guard returns false, navigation is cancelled. If any guard returns a UrlTree, current navigation is cancelled and a new navigation begins to the UrlTree returned from the guard.

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Deprecated: Class-based Route guards are deprecated in favor of functional guards. An injectable class can be used as a functional guard using the inject function: canDeactivate: [() => inject(myGuard).canDeactivate()].

interface CanDeactivate<T> {
  canDeactivate(component: T, currentRoute: ActivatedRouteSnapshot, currentState: RouterStateSnapshot, nextState: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree
}

See also

• CanDeactivateFn

Description

The following example implements a CanDeactivate function that checks whether the current user has permission to deactivate the requested route.

class UserToken {}
class Permissions {
  canDeactivate(user: UserToken, id: string): boolean {
    return true;
  }
}

Here, the defined guard function is provided as part of the Route object in the router configuration:

@Injectable()
class CanDeactivateTeam implements CanDeactivate<TeamComponent> {
  constructor(private permissions: Permissions, private currentUser: UserToken) {}

  canDeactivate(
    component: TeamComponent,
    currentRoute: ActivatedRouteSnapshot,
    currentState: RouterStateSnapshot,
    nextState: RouterStateSnapshot
  ): Observable<boolean|UrlTree>|Promise<boolean|UrlTree>|boolean|UrlTree {
    return this.permissions.canDeactivate(this.currentUser, route.params.id);
  }
}

@NgModule({
  imports: [
    RouterModule.forRoot([
      {
        path: 'team/:id',
        component: TeamComponent,
        canDeactivate: [CanDeactivateTeam]
      }
    ])
  ],
  providers: [CanDeactivateTeam, UserToken, Permissions]
})
class AppModule {}

Methods

canDeactivate()

canDeactivate(component: T, currentRoute: ActivatedRouteSnapshot, currentState: RouterStateSnapshot, nextState: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree Parameters component T currentRoute ActivatedRouteSnapshot currentState RouterStateSnapshot nextState RouterStateSnapshot Returns Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree