The blog is all about access the previous route in your Angular app. In a simple way this service work like:

• it saves the current url, after that, when a NavigationEnd event fires.

• it saves that url in a variable previousUrl, to be get in your component.

First create a new service PreviousRouteService. If you're using the Angular CLI, use the command ng generate service previous-route and add in your app.module file.

Your service file will look like below:

import { Injectable } from '@angular/core';
import { Router, NavigationEnd } from '@angular/router';

@Injectable()
export class PreviousRouteService {

  private previousUrl: string;
  private currentUrl: string;

  constructor(private router: Router) {
    this.currentUrl = this.router.url;
    router.events.subscribe(event => {
      if (event instanceof NavigationEnd) {        
        this.previousUrl = this.currentUrl;
        this.currentUrl = event.url;
      };
    });
  }

  public getPreviousUrl() {
    return this.previousUrl;
  }    
}

You can use in your component like below:

To use the previous route url in your component, first importing the service:

import { PreviousRouteService } from '../services/previous-route.service';

Inject it into the constructor like below:

constructor(
  private previousRouteService: PreviousRouteService
) {}

Now you can access the previous url with this.previousRouteService.getPreviousUrl().

ngOnInit() {
  console.log(this.previousRouteService.getPreviousUrl());
}

Thank you for reading if any suggestion please comment below!!!

Happy Coding!!!