Angular 2不会从AppComponent移动到起始页面

Question

I am trying to learn Angular 2 and play with it now. But I don't know why it doesn't go to start page from AppComponent. As long as I know, this has to move to test page and show "test" text. But when I run this, it only displays "Hello" which is app.component text. If I enter /test url, there is 404 error. Is this because the test component is not loaded successfully?

main.ts

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
 import { AppModule } from './app/app.module';
 platformBrowserDynamic().bootstrapModule(AppModule);

app.module.ts

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { routing } from './app.routing';
import { test } from './test';
@NgModule({
    imports: [
        BrowserModule,
        routing
    ],
    declarations: [
        AppComponent,
        test
    ],
    providers: [
    ],
    bootstrap:    [ AppComponent ]
})
export class AppModule { }

app.routing.ts

 import { NgModule } from '@angular/core';
 import { Routes, RouterModule } from '@angular/router';
 import { test } from './test.index';
 const routes: Routes = [
     { path: '', component: test },
     { path: 'test', component: test },
     { path: '**', redirectTo: '' },
 ];

 export const routing = RouterModule.forRoot(routes);

app.component.ts

  import { Component } from '@angular/core';
    @Component({
      selector: 'my-app',
      template: `<h1>Hello </h1>`,
    })
    export class AppComponent  {  }

test.ts

import { Component } from '@angular/core';

@Component({
    selector: 'test-app',
    template: `<h1>test </h1>`,
})
export class test {}

Answer 1

Include ' <router-outlet></router-outlet> ' in your appcomponent template:

 <div>
      <h3>App component</h3>
    </div>
    <div>
      <router-outlet></router-outlet>
    </div>

Answer 2

It looks like you need to provide a <router-outlet></router-outlet> in your app.component.ts template.

So the test component isn't being loaded because it can't inject the component into anything without the <router-outlet> .

https://angular.io/tutorial/toh-pt5#add-routeroutlet