这可能是由于认证状态信息未能及时更新导致的。可以开启一个可观察数据流，订阅认证状态的更改，并将其保存到localStorage或sessionStorage中。在AuthGuard中，从关联的存储中读取状态信息，而不是直接从认证服务中获取。这样，在页面刷新后，状态信息将保持不变，AuthGuard将能够正确地返回true。

以下是一个可能的实现示例：

// authService.ts

import { Injectable } from '@angular/core'; import { BehaviorSubject } from 'rxjs';

@Injectable({ providedIn: 'root' }) export class AuthService { private isAuthenticated$ = new BehaviorSubject(false);

constructor() { }

login(username: string, password: string) { // authenticate user this.isAuthenticated$.next(true); }

logout() { // de-authenticate user this.isAuthenticated$.next(false); }

isAuthenticated(): Observable { return this.isAuthenticated$.asObservable(); } }

// authGuard.ts

import { Injectable } from '@angular/core'; import { CanActivate, ActivatedRouteSnapshot, RouterStateSnapshot, Router } from '@angular/router'; import { Observable } from 'rxjs'; import { AuthService } from './auth.service';

@Injectable({ providedIn: 'root' }) export class AuthGuard implements CanActivate {

constructor(private authService: AuthService, private router: Router) { }

canActivate( next: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable {

return this.authService.isAuthenticated().pipe(
  map((isAuthenticated) => {
    if (isAuthenticated) {
      return true;
    } else {
      this.router.navigate(['/login']);
      return false;
    }
  })
);

} }

// app.module.ts

import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { RouterModule, Routes } from '@angular/router';

import { AppComponent } from './app.component'; import { LoginComponent } from './login/login.component'; import { HomeComponent } from './home/home.component'; import { AuthGuard } from './auth.guard'; import { AuthService } from './auth.service';

const app