Question

What do you understand by the RouterState?

Answer 1

The RouterState is a tree of activated routes. Every node in this tree knows about the "consumed" URL segments, the extracted parameters, and the resolved data. We can access the current RouterState from anywhere in the application by using the Router service and the routerState property.

1. @Component({templateUrl:'template.html'})  
2. class MyComponent {  
3.   constructor(router: Router) {  
4.     const state: RouterState = router.routerState;  
5.     const root: ActivatedRoute = state.root;  
6.     const child = root.firstChild;  
7.     const id: Observable<string> = child.params.map(p => p.id);  
8.     //...  
9.   }  
10. }