Angular 7：Angular 路由错误 **'router-outlet'** 不是已知元素：

Question

I have tried to include all imports to the necessary files,But I have got the following error while compiling. How could I solve it?

I have generated four differnet commonents Menu,home,contact,and about.Additional to this thare are also Header component that will later help to contain the memu bar to switch between the differnt components.And also footer component.The app-routing.ts and routes.ts files are also attached with this file,which helps for routing purpose.

'router-outlet' is not a known element: 1. If 'router-outlet' is an Angular component, then verify that it is part of this module. 2. If 'router-outlet' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the

'@NgModule.schemas' of this component to suppress this message. ("<app-header></app-header>
    [ERROR ->]<router-outlet></router-outlet>
    <app-footer></app-footer>"): ng:///AppModule/AppComponent.html@1:0
        at syntaxError (compiler.js:1021)
        at TemplateParser.push../node_modules/@angular/compiler/fesm5      /compiler.js.TemplateParser.parse (compiler.js:14830)
        at JitCompiler.push../node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._parseTemplate (compiler.js:24018)
        at JitCompiler.push../node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._compileTemplate (compiler.js:24005)
        at compiler.js:23948
        at Set.forEach (<anonymous>)
        at JitCompiler.push../node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._compileComponents (compiler.js:23948)
        at compiler.js:23858
        at Object.then (compiler.js:1012)
        at JitCompiler.push../node_modules/@angular/compiler/fesm5/compiler.js.JitCompiler._compileModuleAndComponents (compiler.js:23857)


      

routes.ts file

 import { Routes } from '@angular/router'; import { MenuComponent } from '../menu/menu.component'; import { DishdetailComponent } from '../dishdetail/dishdetail.component'; import { HomeComponent } from '../home/home.component'; import { AboutComponent } from '../about/about.component'; import { ContactComponent } from '../contact/contact.component'; export const routes: Routes = [ { path: 'home', component: HomeComponent }, { path: 'menu', component: MenuComponent }, { path: '', redirectTo: '/home', pathMatch: 'full' } ];

app-routing.module.ts file

  
  
  
 
   
 
    
   

 
            import { NgModule } from '@angular/core';
            import { CommonModule } from '@angular/common';
            import { RouterModule, Routes } from '@angular/router';
            
            import { routes } from './routes';
            
            @NgModule({
              imports: [
                CommonModule,
                RouterModule.forRoot(routes)
              ],
              exports: [ RouterModule ],
              declarations: []
            })
            export class AppRoutingModule { }
 
   
 
  


 

app.module.ts file

  
  
  
 
   
 
    
    import { BrowserModule } from '@angular/platform-browser';
    import { NgModule } from '@angular/core';
    import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
    import { MatToolbarModule } from '@angular/material/toolbar';
    import  {MatListModule} from '@angular/material/list';
    import  {MatGridListModule} from '@angular/material/grid-list';
    import  {MatCardModule} from "@angular/material/card";
    import  {MatButtonModule} from "@angular/material/Button";
    import { FlexLayoutModule }  from '@angular/flex-layout';

    import 'hammerjs';

    import { AppComponent } from './app.component';
    import { MenuComponent } from './menu/menu.component';
    import { FooterComponent} from './footer/footer.component';
    import { HeaderComponent} from './header/header.component';
    import { DishdetailComponent } from './dishdetail/dishdetail.component';
    import { HomeComponent } from  './home/home.component'
    import { AboutComponent } from './about/about.component';
    import { ContactComponent } from './contact/contact.component';

    import {DishService} from './services/dish.service';

    import {RouterModule} from '@angular/router';
    import { AppRoutingModule } from './app-routing/app-routing.module';
         @NgModule({
                  declarations: [
                  AppComponent,
                  MenuComponent,
                  DishdetailComponent,
                  HeaderComponent,
                  FooterComponent,
                  HomeComponent,
                  AboutComponent,
                  ContactComponent
                 ],
     imports: [
        BrowserModule,
        BrowserAnimationsModule,
        FlexLayoutModule,
        MatToolbarModule,
        MatGridListModule,
        MatCardModule,
        MatButtonModule,
        MatListModule,
        AppRoutingModule,
        RouterModule
      ],` 
      `providers: [
        DishService
      ],`
     `bootstrap: [AppComponent]` 
   `})` 

    export class AppModule { }
 
   
 
  


          

app.component.html file

 <app-header></app-header> <router-outlet></router-outlet> <app-footer></app-footer>

Answer 1

I see you are missing app-routing.module.ts inside the imports of AppModule

@NgModule({
  imports: [
    CommonModule,
    routingModule
  ],

})
export class AppModule{ }

Answer 2

I noticed that in your app.module.ts file you have back ticks ``` in inappropriate places somewhere around providers & bootstrap array. I copied & pasted this from your own code so you can see it better:

      ...MatListModule,
        AppRoutingModule,
        RouterModule
      ],` 
      `providers: [
        DishService
      ],`
     `bootstrap: [AppComponent]` 
   `})` 

    export class AppModule { }

---

Do this: Remove all the back ticks in the app.module.ts file like I have done below and restart your terminal. This should solve any problems you are having.

      ...MatListModule,
        AppRoutingModule,
        RouterModule
      ],
      providers: [
        DishService
      ],
     bootstrap: [AppComponent]
   })

    export class AppModule { }

---

I copied and pasted your code and worked on the files you provided information about. With the back ticks removed, your code works fine here on my laptop. Here's the result in the gif below, route works properly & no errors in the console. Example with just home & menu components.

Final result:

I removed all other things that didn't relate to routing from your code so that it would be easier to detect errors. Here's my folder structure.

Folder structure:

And here are the contents of my files:

route.ts file:

import { Routes } from '@angular/router';

import { MenuComponent } from './menu/menu.component';
import { HomeComponent } from './menu/home.component';

export const routes: Routes = [
  { path: 'home',  component: HomeComponent },
  { path: 'menu',     component: MenuComponent },
  { path: '', redirectTo: '/home', pathMatch: 'full' }
];

app.module.ts file:

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

import { AppComponent } from './app.component';

import { MenuComponent } from './menu/menu.component';
import { HomeComponent } from './menu/home.component';
import { AppRoutingModule } from './app-routing.module';
import { RouterModule } from '@angular/router';

@NgModule({
  declarations: [
    AppComponent,
    HomeComponent,
    MenuComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    RouterModule
  ],
  providers: [

  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

app.component.ts file:

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

@Component({
  selector: 'app-root',
  template: `
    <router-outlet></router-outlet>
  `
})
export class AppComponent {

}

app-routing.module.ts:

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

import { routes } from './routes';

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

menu.component.ts:

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

@Component({
  template: '<h1>Menu Component</h1>'
})
export class MenuComponent {

}

home.component.ts:

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

@Component({
  template: '<h1>Home Component</h1>'
})
export class HomeComponent {

}

Like I said, once I removed those unnecessary back ticks from the app.module.ts, your code worked fined with no errors.

Answer 3

I have started everything from scratch.Then my issue was fixed.I don't exactly know where is my problem.But,probably I have made routes file in separate folder.Making routes file in app-routing folder, fixed my issue.