The Angular Router maps URL paths to components, enabling navigation in a single-page app without full page reloads. You define a route configuration array linking paths to components.
{ } ;
: = [
{ : , : },
{ : , : },
{ : , : },
{ : , : ().( m.) },
{ : , : },
];
<!-- the router renders the matched component here -->
<router-outlet></router-outlet>
<a routerLink="/users" routerLinkActive="active">Users</a>
<a [routerLink]="['/users', user.id]">View {{ user.name }}</a> <!-- dynamic path -->
routerLink performs client-side navigation (no reload), and routerLinkActive adds a CSS class when the link's route is active — handy for nav highlighting.
import { Router } from "@angular/router";
export class LoginComponent {
constructor(private router: Router) {}
onLogin() {
this.router.navigate(["/dashboard"]); // navigate after an action
}
}
import { ActivatedRoute } from "@angular/router";
export class UserDetailComponent implements OnInit {
constructor(private route: ActivatedRoute) {}
ngOnInit() {
// read :id from the URL (params is an Observable, since it can change)
this.route.params.subscribe(p => this.userId = p["id"]);
// or snapshot for a one-time read:
const id = this.route.snapshot.paramMap.get("id");
}
}
Nested/child routes, route guards (auth), resolvers (pre-fetch data),
query params, and lazy loading of feature routes for code splitting.
The Router is what turns Angular into a multi-view SPA — fast client-side navigation, URL-driven UI, and deep-linkable pages.
Knowing the route config, <router-outlet>, routerLink vs programmatic Router.navigate, and reading params via ActivatedRoute covers the everyday routing needs of any Angular application, with guards and lazy loading building on this foundation.
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