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API > @angular/router

CanActivate

一个接口，某些类可以实现它以扮演一个守卫，来决定该路由能否激活。 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 activated. 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 CanActivate {
  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree
}

说明

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

你还可以转而实现一个带有 canActivate 签名的函数：

You can alternatively provide a function with the canActivate signature:

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

方法

canActivate()

canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree
      
      canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean | UrlTree> | Promise<boolean | UrlTree> | boolean | UrlTree
参数
route ActivatedRouteSnapshot
state RouterStateSnapshot
返回值

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