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API > @angular/router

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()

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