CanDeactivate

一个接口,某些类可以实现它以扮演一个守卫,来决定该路由能否停用。 如果所有守卫都返回 true,就会继续导航。如果任何一个守卫返回了 false,就会取消导航。 如果任何一个守卫返回了 UrlTree,就会取消当前导航,并开始导航到这个守卫所返回的 UrlTree

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

查看"说明"...

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

说明

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|UrlTree>|Promise<boolean|UrlTree>|boolean|UrlTree { 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 {}
      
      
  1. class UserToken {}
  2. class Permissions {
  3. canDeactivate(user: UserToken, id: string): boolean {
  4. return true;
  5. }
  6. }
  7.  
  8. @Injectable()
  9. class CanDeactivateTeam implements CanDeactivate<TeamComponent> {
  10. constructor(private permissions: Permissions, private currentUser: UserToken) {}
  11.  
  12. canDeactivate(
  13. component: TeamComponent,
  14. currentRoute: ActivatedRouteSnapshot,
  15. currentState: RouterStateSnapshot,
  16. nextState: RouterStateSnapshot
  17. ): Observable<boolean|UrlTree>|Promise<boolean|UrlTree>|boolean|UrlTree {
  18. return this.permissions.canDeactivate(this.currentUser, route.params.id);
  19. }
  20. }
  21.  
  22. @NgModule({
  23. imports: [
  24. RouterModule.forRoot([
  25. {
  26. path: 'team/:id',
  27. component: TeamCmp,
  28. canDeactivate: [CanDeactivateTeam]
  29. }
  30. ])
  31. ],
  32. providers: [CanDeactivateTeam, UserToken, Permissions]
  33. })
  34. class AppModule {}

你还可以转而提供具有 canDeactivate 签名的函数:

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 {}
      
      
  1. @NgModule({
  2. imports: [
  3. RouterModule.forRoot([
  4. {
  5. path: 'team/:id',
  6. component: TeamCmp,
  7. canDeactivate: ['canDeactivateTeam']
  8. }
  9. ])
  10. ],
  11. providers: [
  12. {
  13. provide: 'canDeactivateTeam',
  14. useValue: (component: TeamComponent, currentRoute: ActivatedRouteSnapshot, currentState:
  15. RouterStateSnapshot, nextState: RouterStateSnapshot) => true
  16. }
  17. ]
  18. })
  19. class AppModule {}

方法

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

可选. 默认值是 undefined.

返回值

Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree