Angular

What it does

Interface that a class can implement to be a guard deciding if a route can be deactivated.

How to use

class UserToken {}
class Permissions {
  canDeactivate(user: UserToken, id: string): boolean {
    return true;
  }
}
@Injectable()
class CanDeactivateTeam implements CanDeactivate<TeamComponent> {
  constructor(private permissions: Permissions, private currentUser: UserToken) {}
  canDeactivate(
    component: TeamComponent,
    currentRoute: ActivatedRouteSnapshot,
    currentState: RouterStateSnapshot,
    nextState: RouterStateSnapshot
  ): Observable<boolean>|Promise<boolean>|boolean {
    return this.permissions.canDeactivate(this.currentUser, route.params.id);
  }
}
@NgModule({
  imports: [
    RouterModule.forRoot([
      {
        path: 'team/:id',
        component: TeamCmp,
        canDeactivate: [CanDeactivateTeam]
      }
    ])
  ],
  providers: [CanDeactivateTeam, UserToken, Permissions]
})
class AppModule {}

You can alternatively provide a function with the canDeactivate signature:

@NgModule({
  imports: [
    RouterModule.forRoot([
      {
        path: 'team/:id',
        component: TeamCmp,
        canDeactivate: ['canDeactivateTeam']
      }
    ])
  ],
  providers: [
    {
      provide: 'canDeactivateTeam',
      useValue: (component: TeamComponent, currentRoute: ActivatedRouteSnapshot, currentState:
RouterStateSnapshot, nextState: RouterStateSnapshot) => true
    }
  ]
})
class AppModule {}

Interface Overview

interface CanDeactivate {

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

}

Interface Description

Interface Details

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

exported from router/index, defined in router/src/interfaces.ts