CanDeactivate
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.
API
interface CanDeactivate<T> { canDeactivate(component: T, currentRoute: ActivatedRouteSnapshot, currentState: RouterStateSnapshot, nextState: RouterStateSnapshot): any;} canDeactivate
anyTanyDescription
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.
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 ): MaybeAsync<GuardResult> { 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 {}