将主页加载为存储在本地存储中的登陆页面用户 ID

Question

在我的离子应用程序 (v-4) 中，在登录之后，我将 user_id 存储在 local storage 中，如下所示：

onLogin(){
 localStorage.setItem('user_id',  this.loginForm.user_id);
}

并且我已将 login page 设置为 landing page，在 login page 之后，用户将被路由 home page。此路由工作正常。
但是，如果用户再次打开 app 它应该显示 home page 作为着陆页，因为应用程序已经将 user_id 存储在其 local storage.

代码

app.component.html

<ion-router-outlet main></ion-router-outlet>

app.component.ts

import { Component } from '@angular/core';
import { Platform } from '@ionic/angular';
import { SplashScreen } from '@ionic-native/splash-screen/ngx';
import { StatusBar } from '@ionic-native/status-bar/ngx';

@Component({
  selector: 'app-root',
  templateUrl: 'app.component.html'
})
export class AppComponent {

  constructor(
    private platform: Platform,
    private splashScreen: SplashScreen,
    private statusBar: StatusBar
  ) {
    this.initializeApp();
  }

  initializeApp() {
    this.platform.ready().then(() => {
      this.statusBar.styleDefault();
    });
  }
}

app.module.ts

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

import { IonicModule, IonicRouteStrategy } from '@ionic/angular';
import { SplashScreen } from '@ionic-native/splash-screen/ngx';
import { StatusBar } from '@ionic-native/status-bar/ngx';
import { AppComponent } from './app.component';
import { AppRoutingModule } from './app-routing.module';
import { HttpClientModule } from '@angular/common/http';
import { HttpModule } from '@angular/http';

import { FormsModule, ReactiveFormsModule } from '@angular/forms';
@NgModule({
  declarations: [AppComponent],
  entryComponents: [],
  imports: [
    BrowserModule,
    IonicModule.forRoot(),
    AppRoutingModule,
    HttpModule,
    HttpClientModule,
    FormsModule,
    ReactiveFormsModule ,
  ],
  providers: [
    StatusBar,
    SplashScreen,
    { provide: RouteReuseStrategy, useClass: IonicRouteStrategy }
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

app.routing.module.ts

import { NgModule } from '@angular/core';
import { PreloadAllModules, RouterModule, Routes } from '@angular/router';

const routes: Routes = [
  {
    path: '',
    redirectTo: 'login',
    pathMatch: 'full'
  },
  {
    path: 'home',
    loadChildren: './home/home.module#HomePageModule'
  },
  { path: 'login', loadChildren: './login/login.module#LoginPageModule' },
  { path: 'my-profile', loadChildren: './my-profile/my-profile.module#MyProfilePageModule' },
  { path: 'appointments', loadChildren: './appointments/appointments.module#AppointmentsPageModule' },
  { path: 'request-acceptance', loadChildren: './request-acceptance/request-acceptance.module#RequestAcceptancePageModule' },
];

@NgModule({
  imports: [
    RouterModule.forRoot(routes, { preloadingStrategy: PreloadAllModules })
  ],
  exports: [RouterModule]
})
export class AppRoutingModule { }

我发现这个类似但我无法在我的应用程序中执行此操作。

Answer 1

实施一个守卫，如果用户登录则重定向到主页试试这个：

在src/guard/auth.guard.ts

创建守卫

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

@Injectable({
  providedIn: 'root'
})
export class AuthGuard implements CanActivate {
  constructor(
    private router:Router,
  ){}
  canActivate(
    next: ActivatedRouteSnapshot,
    state: RouterStateSnapshot): Observable<boolean> | Promise<boolean> | boolean {
      if(localStorage.getItem('user_id') != undefined || null){
        return true;
      }else{
        this.router.navigate(['/login']);
        return false;
      }
  }
}

app.component.ts

import { Component } from '@angular/core';
import { Platform } from '@ionic/angular';
import { SplashScreen } from '@ionic-native/splash-screen/ngx';
import { StatusBar } from '@ionic-native/status-bar/ngx';

@Component({
  selector: 'app-root',
  templateUrl: 'app.component.html'
})
export class AppComponent {

  constructor(
    private platform: Platform,
    private splashScreen: SplashScreen,
    private statusBar: StatusBar
  ) {
    this.initializeApp();
  }

  initializeApp() {
    this.platform.ready().then(() => {
      this.statusBar.styleDefault();
    });
    if (localStorage.getItem("user_id") != undefined || null) {
      this.router.navigate(['/home']);
    } else {
      this.router.navigate(['/login'])
    }
  }
}

app-routing.module.ts

import { NgModule } from '@angular/core';
import { PreloadAllModules, RouterModule, Routes } from '@angular/router';
import {AuthGuard} from './guard/auth.guard'; //add this

const routes: Routes = [
  {
    path: '',
    redirectTo: 'login',
    pathMatch: 'full'
  },
  {
    path: 'home',
    loadChildren: './home/home.module#HomePageModule',canActivate:[AuthGuard]  //Use canActive:[AuthGuard] to protect routing if user is not logged in.
  },
  { path: 'login', loadChildren: './login/login.module#LoginPageModule' },
  { path: 'my-profile', loadChildren: './my-profile/my-profile.module#MyProfilePageModule'},
  { path: 'appointments', loadChildren: './appointments/appointments.module#AppointmentsPageModule' },
  { path: 'request-acceptance', loadChildren: './request-acceptance/request-acceptance.module#RequestAcceptancePageModule' },
];

@NgModule({
  imports: [
    RouterModule.forRoot(routes, { preloadingStrategy: PreloadAllModules })
  ],
  exports: [RouterModule]
})
export class AppRoutingModule { }

app.module.ts

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

import { IonicModule, IonicRouteStrategy } from '@ionic/angular';
import { SplashScreen } from '@ionic-native/splash-screen/ngx';
import { StatusBar } from '@ionic-native/status-bar/ngx';
import { AppComponent } from './app.component';
import { AppRoutingModule } from './app-routing.module';
import { HttpClientModule } from '@angular/common/http';
import { HttpModule } from '@angular/http';
import {AuthGuard} from './guard/auth.guard'; //add this

import { FormsModule, ReactiveFormsModule } from '@angular/forms';
@NgModule({
  declarations: [AppComponent],
  entryComponents: [],
  imports: [
    BrowserModule,
    IonicModule.forRoot(),
    AppRoutingModule,
    HttpModule,
    HttpClientModule,
    FormsModule,
    ReactiveFormsModule ,
  ],
  providers: [
    StatusBar,
    SplashScreen,
    AuthGuard, //add this
    { provide: RouteReuseStrategy, useClass: IonicRouteStrategy }
  ],
  bootstrap: [AppComponent]
})
export class AppModule {}

Answer 2

将您的登录组件设置为默认页面。在登录组件中

ngOninit(){
if(localStorage.getItem('user_id') != undefined || null){
    //Redirect to Homepage
}
else{
    //do nothing
   }
}

当您加载第一个页面（即登录页面）时。它将检查您是否将登录 ID 存储在本地存储中，因为我们在登录页面的 Oninit 中写了条件。如果是，它会自动重定向到您的主页，如果不是，那么它将保留在同一页面。

将主页加载为存储在本地存储中的登陆页面用户 ID

Load home page as landing page user Id stored in local storage

ionic-framework

angular

ionic4