运行第二个Observable是第一个Observable是false

Question

我在 Angular 9 中创建了以下 AuthenticatedGuard：

export class AuthenticatedGuard implements CanActivate {

  constructor(private authenticationService: AuthenticationService) { }

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {

      return this.authenticationService.isSignedIn();

      this.authenticationService.signInRedirect({ state: { url: state.url }}).subscribe();

  }

}

方法 authenticationService.isSignedIn returns Observable<boolean> 和 authenticationService.signInRedirect() returns Observable<any>.

行为应该是：

如果 authenticationService.isSignedIn 是 false 则执行：

this.authenticationService.signInRedirect({ state: { url: state.url }}).subscribe();

可以这样做并仍然使用 Observable 吗？

Answer 1

将保护更改为：-

export class AuthenticatedGuard implements CanActivate {

  constructor(private authenticationService: AuthenticationService) { }

  canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {

      return this.authenticationService.isSignedIn().pipe(tap((res)=> {
            if(!res) {
              this.authenticationService.signInRedirect({ state: { url: state.url }}).subscribe();
            }
      }));;

  }

}

Answer 2

您可以调用 isSignedIn() 然后执行 signInRedirect() 重定向，我们还需要 return 一个 true/false 值。

async canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {
  const isSignedIn = awiat this.authenticationService.isSignedIn().first().toPromise();
  if (!isSignedIn) {
    this.authenticationService.signInRedirect({ state: { url: state.url }}).subscribe();
    return false;
  }
  return true;
}

运行第二个Observable是第一个Observable是false

Run a second Observable is first Observable is false

rxjs

angular

angular9