How does the loading of lazy-loaded modules work?
In Angular, lazy-loaded modules are loaded only when the user navigates to a specific route, not when the application starts.
Key points
- Configuring a route for lazy loading:
ts
const routes: Routes = [
{
path: 'admin',
loadChildren: () =>
import('./admin/admin.module').then(m => m.AdminModule)
}
];loadChildrenspecifies a function that dynamically imports the module throughimport().
- What happens when you navigate to the route:
- Angular calls the
loadChildrenfunction. - The browser loads the module's JS file over the network.
- An instance of the module and its components is created, and its routes and services are registered.
- Advantages:
- Reduces the size of the application's main bundle.
- Improves the application's startup time, since not all modules need to be loaded at once.
- Effect on the lifecycle:
- The lifecycle hooks of the module's components (
ngOnInit,ngAfterViewInit, etc.) are called only after the lazy module is loaded and rendered. - A lazy-loaded module is created dynamically, as if it had been created separately.
In other words, a lazy-loaded module is loaded on demand, through a dynamic import, and its components and services are initialized only when you navigate to the corresponding route.
Short Answer
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