重置Angular 2应用 [英] Resetting Angular 2 App

问题描述

我的Angular 2应用程序具有注销功能.我们希望尽量避免重新加载页面(即document.location.href = '/';)，但是注销过程需要重置应用程序，以便当另一个用户登录时，上一会话没有剩余数据.

My Angular 2 app has a logout feature. We want to avoid doing a page reload if we can (i.e. document.location.href = '/';), but the logout process needs to reset the app so when another user logs in there's no residual data from the previous session.

这是我们的main.ts文件:

Here's our main.ts file:

import 'es6-shim/es6-shim';
import './polyfills';    
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { ComponentRef, enableProdMode } from '@angular/core';
import { environment } from '@environment';
import { AppModule } from './app/app.module';

if (environment.production === true) {
    enableProdMode();
}

const init = () => {
  platformBrowserDynamic().bootstrapModule(AppModule)
  .then(() => (<any>window).appBootstrap && (<any>window).appBootstrap())
  .catch(err => console.error(err));
};

init();

platformBrowserDynamic().onDestroy(() => {
  init();
});

您可以看到在应用程序被销毁时，我正在尝试调用init()方法.我们的user-authentication.service中的注销方法会启动destroy:

You can see that I'm trying to call the init() method when the application is destroyed. The logout method in our user-authentication.service initiates destroy:

logout() {   
  this.destroyAuthToken();  
  this.setLoggedIn(false);
  this.navigateToLogin()
  .then(() => {
    platformBrowserDynamic().destroy();
  });
}

这会出现以下错误:

选择器"app-root"与任何元素都不匹配

The selector "app-root" did not match any elements

任何帮助表示赞赏.

推荐答案

我最终弄清楚了这一点.这可以比我的实现更简单地完成，但是我想将引导程序保留在main.ts中，而不是将其保留在请求重新启动的服务中.

I ended up figuring this out in the end. This could be done more simply than my implementation, but I wanted to keep the bootstrapping in main.ts rather than stick it in the service that requests the restart.

1. 创建一个单例，为Angular和非Angular(main.ts)进行通信提供一种方式:

1. Create a singleton that provides a way for Angular and non-Angular (main.ts) to communicate:

boot-control.ts:

import { Observable } from 'rxjs/Observable';
import { Subject } from 'rxjs/Subject';
export class BootController {
  private static instance: BootController;
  private _reboot: Subject<boolean> = new Subject();
  private reboot$ = this._reboot.asObservable();

  static getbootControl() {
    if (!BootController.instance) {
      BootController.instance = new BootController();
    }
    return BootController.instance;
  }

  public watchReboot() {
    return this.reboot$;
  }

  public restart() {
    this._reboot.next(true);
  }
}

1. 调整main.ts以订阅重新启动请求:

1. Adjust main.ts to subscribe to the reboot request:

main.ts:

import { enableProdMode, NgModuleRef, NgModule } from '@angular/core';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app/app.module';
import { environment } from './environments/environment';
import { BootController } from './boot-control';

if (environment.production) {
  enableProdMode();
}

const init = () => {
  platformBrowserDynamic().bootstrapModule(AppModule)
  .then(() => (<any>window).appBootstrap && (<any>window).appBootstrap())
  .catch(err => console.error('NG Bootstrap Error =>', err));
}

// Init on first load
init();

// Init on reboot request
const boot = BootController.getbootControl().watchReboot().subscribe(() => init());

1. 将NgZone添加到触发注销的服务中:

user-auth.service.ts:

import { BootController } from '@app/../boot-control';
import { Injectable, NgZone } from '@angular/core';

@Injectable()
export class UserAuthenticationService {
    constructor (
        private ngZone: NgZone,
        private router: Router
    ) {...}

    logout() {
        // Removes auth token kept in local storage (not strictly relevant to this demo)
        this.removeAuthToken();

        // Triggers the reboot in main.ts        
        this.ngZone.runOutsideAngular(() => BootController.getbootControl().restart());

        // Navigate back to login
        this.router.navigate(['login']);
    }
}

NgZone的要求是避免发生错误:

The NgZone requirement is to avoid the error:

预计不在Angular Zone中，但确实如此！

Expected to not be in Angular Zone, but it is!

这篇关于重置Angular 2应用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！