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.
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
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
Parameters
Returns
|