Introduction
Angular Router is an important part of creating a Single Page Application (SPA) in Angular. It is used to enable navigation between different views or components in an application. It allows users to stay on the same page while the application updates the content of a particular section dynamically. The Angular Router Events are essentially a group of events that are fired at different stages of navigation, providing developers with additional control over the navigation process. In this article, we will dive more in-depth into the Angular Router Events and how to use them.
Angular Router Events
The Angular Router Events are a group of events that are fired at different stages of navigation. They are important because they allow developers to control and manage the different stages of navigation. The following are the Angular Router Events that will be discussed:
1. NavigationStart: This event is fired when navigation starts.
2. RouteConfigLoadStart: This event is fired when the Router starts loading the configuration for the route.
3. RouteConfigLoadEnd: This event is fired when the Router finishes loading the configuration for the route.
4. RoutesRecognized: This event is fired when the Router recognizes a route.
5. GuardsCheckStart: This event is fired when the Router starts checking all the guards that are associated with the route.
6. ChildActivationStart: This event is fired when the Router starts activating a child route.
7. ActivationStart: This event is fired when the Router starts activating a route.
8. GuardsCheckEnd: This event is fired when the Router finishes checking all the guards that are associated with the route.
9. ResolveStart: This event is fired when the Router starts resolving all the data needed to display the route.
10. ResolveEnd: This event is fired when the Router finishes resolving all the data needed to display the route.
11. ActivationEnd: This event is fired when the Router finishes activating a route.
12. ChildActivationEnd: This event is fired when the Router finishes activating a child route.
13. NavigationEnd: This event is fired when navigation ends successfully.
14. NavigationCancel: This event is fired when navigation is canceled.
15. NavigationError: This event is fired when navigation fails due to an error.
How to use Angular Router Events
Using Angular Router Events is relatively straightforward. Developers can subscribe to any of the aforementioned events using the Angular Router instance in their components. This can be done in the ngOnInit() lifecycle hook of the component. An example of subscribing to the NavigationStart event is as follows:
“`
import { Component, OnInit } from ‘@angular/core’;
import { Router, NavigationStart } from ‘@angular/router’;
@Component({
selector: ‘app-example’,
templateUrl: ‘./example.component.html’,
styleUrls: [‘./example.component.css’]
})
export class ExampleComponent implements OnInit {
constructor(private router: Router) { }
ngOnInit() {
this.router.events.subscribe(event => {
if (event instanceof NavigationStart) {
// do something
}
});
}
}
“`
FAQ
Q. What is the use of Angular Router Events?
A. Angular Router Events allow developers to control and manage the different stages of navigation in an application.
Q. How many Router Events are there in Angular?
A. There are 15 Router Events in Angular.
Q. How can I listen to Angular Router Events?
A. You can subscribe to Angular Router Events using the Angular Router instance in your components.
Q. How can I listen to a specific Angular Router Event?
A. You can check the instance of the event using the instanceof operator in your subscribe method.
Q. Is it mandatory to subscribe to all Angular Router Events?
A. No, it is not mandatory to subscribe to all Angular Router Events. You can subscribe to the events that are relevant to your use-case.
Conclusion
Angular Router Events are a powerful tool that allows developers to control and manage the different stages of navigation in an application. They are important because they provide developers with additional control over the navigation process. In this article, we explored the different Angular Router Events and how to use them. We also included a FAQ section for further understanding. Hopefully, this article provides you with a better understanding of Angular Router Events and how they can be used in your Angular projects.