CanDeactivate
interface
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.
interface CanDeactivate<T> {
canDeactivate(component: T, currentRoute: ActivatedRouteSnapshot, currentState: RouterStateSnapshot, nextState?: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree
}
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 {}
You can alternatively provide an in-line function with the canDeactivate
signature:
@NgModule({
imports: [
RouterModule.forRoot([
{
path: 'team/:id',
component: TeamComponent,
canDeactivate: ['canDeactivateTeam']
}
])
],
providers: [
{
provide: 'canDeactivateTeam',
useValue: (component: TeamComponent, currentRoute: ActivatedRouteSnapshot, currentState:
RouterStateSnapshot, nextState: RouterStateSnapshot) => true
}
]
})
class AppModule {}
Methods
canDeactivate() | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
canDeactivate(component: T, currentRoute: ActivatedRouteSnapshot, currentState: RouterStateSnapshot, nextState?: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTreeParameters
Returns
|
© 2010–2020 Google, Inc.
Licensed under the Creative Commons Attribution License 4.0.
https://v10.angular.io/api/router/CanDeactivate