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[Done Quick] Easy Lazy loading with Angular 8

nitinja profile image Nitin Jadhav ・1 min read

Here are the steps to quickly add lazy loaded modules (loads only after the user navigates to a specific feature or page):

Note that your app must be arranged as feature modules instead of one big AppModule. Make sure that you have installed latest angular cli with the command npm install -g @angular/cli.

step 1: create a Demo App

ng new MyApp --routing

step 2: Add a feature module and component inside the new module which needs to be lazily loaded

ng g module feature --routing
ng g component MyFeature --module=feature

step 3: In your app.component.html add a link to the lazy module

<a routerLink="/feature">Lazy feature</a>
note that this file also has <router-outlet></router-outlet>

step 4: Add Lazy loading to the main app router file (app-routing.module.ts). Notice the import statement - this is where the magic happens!

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

const routes: Routes = [
  {
    path: 'feature',
    loadChildren: () =>
      import('./feature/feature.module').then(module => module.FeatureModule)
  }
];

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

step 5: Finally, add lazy routing to feature module routing file (feature-routing.module.ts)

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { MyFeatureComponent } from '../my-feature/my-feature.component';

const routes: Routes = [{
  path: '',
  component: MyFeatureComponent
}];

@NgModule({
  imports: [RouterModule.forChild(routes)],
  exports: [RouterModule]
})
export class FeatureRoutingModule { }

That's it! Run the project with ng serve and click the link in your new app. See the browser console for the lazy loaded module.

Devtools show lazy angular module loading

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