angular 2 router.navigate不导航到正确的URL

Question

我正在使用登录并希望重定向到已保存的网址状态。

login(username: string, password: string) {
return this.http.post('/api/authenticate', JSON.stringify({ username: username, password: password }))
  .map((response: Response) => {
    // login successful if there's a jwt token in the response
    let user = response.json();
    if (user && user.token) {
      // store user details and jwt token in local storage to keep user logged in between page refreshes
      localStorage.setItem('currentUser', JSON.stringify(user));
      this.alertService.success("Login success", true);
      this.location.back();
    }
  });

}

这是我在这里观察的登录信息

login() {
this.loading = true;
this.authService.login(this.model.username, this.model.password)
  .subscribe(() => {
      this.router.navigate([this.returnUrl]);
    },
    error => {
      this.alertService.error(error);
      this.loading = false;
    });

}

问题：this.router.navigate([this.returnUrl]);不导航到returnUrl。但是当我正在调试时，保存了正确的URL。