How to determine previous page URL in Angular?

Question

Suppose I am currently on the page which has the URL /user/:id . Now from this page I navigate to next page :id/posts.

Now Is there a way, so that i can check what is the previous URL, i.e. /user/:id.

Below are my routes

export const routes: Routes = [
  { 
    path: 'user/:id', component: UserProfileComponent
  },
  {  
    path: ':id/posts', component: UserPostsComponet 
  }
];

Answer 1

Maybe all other answers are for angular 2.X.

Now it doesn't work for angular 5.X. I'm working with it.

with only NavigationEnd, you can not get previous url.

because Router works from "NavigationStart", "RoutesRecognized",..., to "NavigationEnd".

You can check with

router.events.forEach((event) => {
  console.log(event);
});

But still you can not get previous url even with "NavigationStart".

Now you need to use pairwise.

import 'rxjs/add/operator/filter';
import 'rxjs/add/operator/pairwise';

constructor(private router: Router) {
  this.router.events
    .filter(e => e instanceof RoutesRecognized)
    .pairwise()
    .subscribe((event: any[]) => {
      console.log(event[0].urlAfterRedirects);
    });
}
    

With pairwise, You can see what url is from and to.

"RoutesRecognized" is the changing step from origin to target url.

so filter it and get previous url from it.

Last but not least,

put this code in parent component or higher (ex, app.component.ts)

because this code fires after finish routing.

Update angular 6+

The events.filter gives error because filter is not part of events, so change the code to

import { filter, pairwise } from 'rxjs/operators';

this.router.events
.pipe(filter((evt: any) => evt instanceof RoutesRecognized), pairwise())
.subscribe((events: RoutesRecognized[]) => {
  console.log('previous url', events[0].urlAfterRedirects);
  console.log('current url', events[1].urlAfterRedirects);
});

Answer 2

You can subscribe to route changes and store the current event so you can use it when the next happens

previousUrl: string;
constructor(router: Router) {
  router.events
  .pipe(filter(event => event instanceof NavigationEnd))
  .subscribe((event: NavigationEnd) => {
    console.log('prev:', event.url);
    this.previousUrl = event.url;
  });
}

See also How to detect a route change in Angular?

Answer 3

Create a injectable service:

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

 /** A router wrapper, adding extra functions. */
@Injectable()
export class RouterExtService {
  
  private previousUrl: string = undefined;
  private currentUrl: string = undefined;

  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;
  }    
}

Then use it everywhere you need. To store the current variable as soon as possible, it's necessary to use the service in the AppModule.

// AppModule
export class AppModule {
  constructor(private routerExtService: RouterExtService){}

  //...

}

// Using in SomeComponent
export class SomeComponent implements OnInit {
  
  constructor(private routerExtService: RouterExtService, private location: Location) { } 

  public back(): void {
    this.location.back();
  }

  //Strange name, but it makes sense. Behind the scenes, we are pushing to history the previous url
  public goToPrevious(): void {
    let previous = this.routerExtService.getPreviousUrl();
    
    if(previous)
      this.routerExtService.router.navigateByUrl(previous);
  }

  //...

}

Answer 4

Angular 6 updated code for getting previous url as string.

import { Router, RoutesRecognized } from '@angular/router';
import { filter, pairwise } from 'rxjs/operators';


export class AppComponent implements OnInit {
    
  constructor (
    public router: Router
  ) { }
    
  ngOnInit() {
    this.router.events
      .pipe(filter((e: any) => e instanceof RoutesRecognized),
        pairwise()
      ).subscribe((e: any) => {
    console.log(e[0].urlAfterRedirects); // previous url
  });
}

Answer 5

Angular 8 & rxjs 6 in 2019 version

I would like to share the solution based on others great solutions.

First make a service to listen for routes changes and save the last previous route in a Behavior Subject, then provide this service in the main app.component in constructor then use this service to get the previous route you want when ever you want.

use case: you want to redirect the user to an advertise page then auto redirect him/her to where he did came from so you need the last previous route to do so.

// service : route-events.service.ts

import { Injectable } from '@angular/core';
import { Router, RoutesRecognized } from '@angular/router';
import { BehaviorSubject } from 'rxjs';
import { filter, pairwise } from 'rxjs/operators';
import { Location } from '@angular/common';

@Injectable()
export class RouteEventsService {

    // save the previous route
  public previousRoutePath = new BehaviorSubject<string>('');

  constructor(
    private router: Router,
    private location: Location
  ) {

    // ..initial prvious route will be the current path for now
    this.previousRoutePath.next(this.location.path());


    // on every route change take the two events of two routes changed(using pairwise)
    // and save the old one in a behavious subject to access it in another component
    // we can use if another component like intro-advertise need the previous route
    // because he need to redirect the user to where he did came from.
    this.router.events.pipe(
      filter(e => e instanceof RoutesRecognized),
      pairwise(),
        )
    .subscribe((event: any[]) => {
        this.previousRoutePath.next(event[0].urlAfterRedirects);
    });

  }
}

provide the service in app.module

  providers: [
    ....
    RouteEventsService,
    ....
  ]

Inject it in app.component

  constructor(
    private routeEventsService: RouteEventsService
  )

finally use the saved previous route in the component you want

  onSkipHandler(){
    // navigate the user to where he did came from
    this.router.navigate([this.routeEventsService.previousRoutePath.value]);
  }

Answer 6

This worked for me in angular >= 6.x versions:

this.router.events
            .subscribe((event) => {
              if (event instanceof NavigationStart) {
                window.localStorage.setItem('previousUrl', this.router.url);
              }
            });

Answer 7

I'm using Angular 8 and the answer of @franklin-pious solves the problem. In my case, get the previous url inside a subscribe cause some side effects if it's attached with some data in the view.

The workaround I used was to send the previous url as an optional parameter in the route navigation.

this.router.navigate(['/my-previous-route', {previousUrl: 'my-current-route'}])

And to get this value in the component:

this.route.snapshot.paramMap.get('previousUrl')

this.router and this.route are injected inside the constructor of each component and are imported as @angular/router members.

import { Router, ActivatedRoute }   from '@angular/router';

Answer 8

FOR ANGULAR 7+

Actually since Angular 7.2 there is not need to use a service for saving the previous url. You could just use the state object to set the last url before linking to the login page. Here is an example for a login scenario.

@Component({ ... })
class SomePageComponent {
  constructor(private router: Router) {}

  checkLogin() {
    if (!this.auth.loggedIn()) {
      this.router.navigate(['login'], { state: { redirect: this.router.url } });
    }
  }
}

@Component({...})
class LoginComponent {
  constructor(private router: Router) {}

  backToPreviousPage() {
    const { redirect } = window.history.state;

    this.router.navigateByUrl(redirect || '/homepage');
  }
}

----------------

Additionally you could also pass the data in the template:

@Component({
  template: '<a routerLink="/some-route" [state]="{ redirect: router.url}">Go to some route</a>'
})
class SomePageComponent {
  constructor(public router: Router) {}
}

Answer 9

Easiest way

As mentioned here, please simply use Location which come from @angular/common.

Example

In your component.ts

import { Location } from '@angular/common';


@Component({...})
export class AuthenticationComponent {
    constructor(private _location: Location) {}

    public returnPreviousUrl(): void {
        this._location.back();
    }
}

In your component.html

<div (click)="returnPreviousUrl()">return</div>

Answer 10

You can use Location as mentioned here.

Here's my code if the link opened on new tab

navBack() {
    let cur_path = this.location.path();
    this.location.back();
    if (cur_path === this.location.path())
     this.router.navigate(['/default-route']);    
  }

Required imports

import { Router } from '@angular/router';
import { Location } from '@angular/common';

Answer 11

@GünterZöchbauer also you can save it in localstorage but I not prefer it ) better to save in service and get this value from there

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

Answer 12

Pretty simple by using previousNavigation object:

this.router.events
  .pipe(
    filter(e => e instanceof NavigationEnd && this.router.getCurrentNavigation().previousNavigation),
    map(() => this.router.getCurrentNavigation().previousNavigation.finalUrl.toString()),
  )
  .subscribe(previousUrl => {}); 

Answer 13

Most up-to-date complete answer including refreshes.

the service

import { Injectable} from '@angular/core';
import { Router, NavigationEnd } from '@angular/router';
import { filter, pairwise } from 'rxjs/operators';

@Injectable()
export class RouterService{

    private prevUrl?: any = undefined;

    constructor(private router: Router){
        router.events.pipe(
            filter(e => e instanceof NavigationEnd),
            pairwise()          
        ).subscribe(x=>{            
           this.prevUrl = x[0].urlAfterRedirects;           
           localStorage.setItem("prevUrl", this.prevUrl);
        })
    }
    public getPrevUrl(){
        console.log(this.prevUrl)
        return this.prevUrl;
    }
    public getCurrUrl(){
        return  this.router.url;
    }
    public checkStorage(){
        console.log("checkign storage")
        this.prevUrl= localStorage.getItem("prevUrl")
    }
}

app.component

import { RouterService } from './shared/services/router-service';

export class AppComponent {

  constructor(private routerSvc: RouterService ) {}
  ngOnInit() {
    this.routerSvc.checkStorage()
  }
}

inlcuse service in App.module

@NgModule({
...
  providers: [
    RouterService
  ],

in component

import { RouterService  } from '../services/router-service';

export class MyComponent implements OnInit {

  constructor(private routerSvc: RouterService) { }
  
  ngOnInit(): void {    
    console.log(this.routerSvc.getPrevUrl())
  }

}

Answer 14

You can try this sample code:

import {Router, RoutesRecognized, Event} from '@angular/router';
import {filter, pairwise} from 'rxjs/operators';
 
previousUrl = '';

constructor(
  private readonly location: Location, private readonly router: Router) {
    this.router.events
      .pipe(filter((evt: Event): evt is RoutesRecognized => evt instanceof RoutesRecognized), pairwise())
      .subscribe((events: RoutesRecognized[]) => {
        this.previousUrl = events[0].urlAfterRedirects;
    });
  }

Type declaration of 'any' loses type-safety. It's better to provide a more specific type.

TypeScript's any type is a super and subtype of all other types, and allows dereferencing all properties. As such, any is dangerous - it can mask severe programming errors, and its use undermines the value of having static types in the first place.

Answer 15

Angular 12

const prevUrl = this.router.getCurrentNavigation().previousNavigation?.finalUrl.toString();
console.log(prevUrl);

Answer 16

I had some struggle to access the previous url inside a guard.
Without implementing a custom solution, this one is working for me.

public constructor(private readonly router: Router) {
};

public ngOnInit() {
   this.router.getCurrentNavigation().previousNavigation.initialUrl.toString();
}

The initial url will be the previous url page.

Answer 17

This simple solution worked for me.

import 'rxjs/add/operator/pairwise';
import { Router } from '@angular/router';

export class TempComponent {
    constructor(private router: Router) {
        this.router.events.pairwise().subscribe((event) => {
            console.log(event); // NavigationEnd will have last and current visit url
        });
    };
}

Answer 18

    import { Router, RoutesRecognized } from '@angular/router';
    import { filter, pairwise } from 'rxjs/operators';
    
    constructor(
        private router: Router
      ) {
        
      }
    
    ngOnInit(){
    this.router.events
    .pipe(filter((evt: any) => evt instanceof RoutesRecognized), pairwise())
    .subscribe((events: RoutesRecognized[]) => {
      
       let prevUrl = events[0].urlAfterRedirects;
      console.log('previous url', prevUrl);
      console.log('current url', events[1].urlAfterRedirects);
    });
    }

Answer 19

Reference : Get Previous URL in Angular

Using as part of a service is better approach

    @Injectable({
      providedIn: 'root'
    })
    export class RoutingStateService
    {
      private history = [];
    
      constructor(private router: Router)
      {
        this.loadRouting();
      }
    
      public loadRouting(): void
      {
        this.router.events
          .pipe(filter(event => event instanceof NavigationEnd))
          .subscribe(({urlAfterRedirects}: NavigationEnd) => {
            this.history = [...this.history, urlAfterRedirects];
          });
      }
    
      public getHistory(): string[]
      {
        return this.history;
      }
    
      public getPreviousUrl(): string
      {
        return this.history[this.history.length - 2];
      }
    }

Next in your component on init

    ngOnInit(): void {
         this.routingStateService.loadRouting()
      }

Now you can get the previous url by calling getPreviousUrl() method from service

Answer 20

There is an issue in the Angular GitHub that's being considered right now that would make this super easy, i.e., Router.previousUrl. Please put your on the issue to make it cross the required 20 in order to make it into the backlog:

https://github.com/angular/angular/issues/45685

Answer 21

You can simply use the solution with RXJX exemple inspiration

app.componennt.html

<p>Previous URL: {{ previousUrl }}</p>
<p>Current URL: {{ currentUrl }}</p>

app.component.ts

previousUrl: string = null
currentUrl: string = null

ngOnInit() {
    this.router.events.pipe(
      filter((event) => event instanceof NavigationEnd)
    ).subscribe((event: NavigationEnd) => {
      this.previousUrl = this.currentUrl;
      this.currentUrl = event.url;
      this.urlService.setPreviousUrl(this.previousUrl);
    });
  }

injector service

import { Injectable } from '@angular/core';
import { BehaviorSubject, Observable, take } from 'rxjs';

@Injectable()
export class UrlService {
  private previousUrl: BehaviorSubject<string> = new BehaviorSubject<string>(null);
  public previousUrl$: Observable<string> = this.previousUrl.asObservable();

  constructor() { }
  setPreviousUrl(previousUrl: string) {
    this.previousUrl.next(previousUrl);
  }
}

wanted.component.ts, just implement previous function to navigate

public goToPrevious(): void {
    let obsValue = undefined;
    const sub = this.urlService.previousUrl$.pipe(take(1)).subscribe(value => obsValue = value);
    sub.unsubscribe();

    console.log('url', obsValue)
    this.router.navigateByUrl(obsValue)
}

You can also show the in previous value in template with pipe async

other.component.html

<p>Previous URL: {{ previousUrl | async }}</p>

other.component.ts

export class OtherComponent implements OnInit {
  previousUrl: Observable<string> = this.urlService.previousUrl$;
  constructor(private urlService: UrlService) { }

  ngOnInit() {
    this.urlService.previousUrl$.subscribe((previousUrl: string) => {
      console.log('previous url: ', previousUrl);
    });
  }
}

Answer 22

You can fire an Angular service at the first start of your application like below. Be careful to import and use this service in your app root module.

Navigation Service

import {Inject, Injectable, PLATFORM_ID} from "@angular/core";
import { Subject } from "rxjs";
import { untilDestroyed } from "@ngneat/until-destroy";
import { filter, map, pairwise } from "rxjs/operators";
import { NavigationEnd, Router } from "@angular/router";

export interface ITFNavigationEnd {
    id: number;
    url: string;
    urlAfterRedirects: string;
}

export interface ITFPrevAndCurrentUrl {
    previousUrl: string;
    currentUrl: string;
}

@Injectable()
export class NavigationService {
    
    private subjectPrevAndCurrUrl: Subject<ITFPrevAndCurrentUrl> = new Subject<ITFPrevAndCurrentUrl>();
    public prevAndCurrUrl$ = this.subjectPrevAndCurrUrl.asObservable();

    private urlHistory: string[] = [];

    private _previousUrl: string;
    private _currentUrl: string;

    private firstRecord: boolean = false;

    set previousUrl(url: string) {
        this._previousUrl = url;
    }

    get previousUrl(): string {
        return this._previousUrl;
    }

    set currentUrl(url: string) {
        this._currentUrl = url;
    }

    get currentUrl(): string {
        return this._currentUrl;
    }

    constructor(@Inject(PLATFORM_ID) private platformId: any,
                private router: Router) {

        // Record changing of all url
        this.recordUrlHistory();
    }

    private recordUrlHistory(): void {

        // Quantify initial value for current value
        this.currentUrl = this.router.url;

        // Only works first time of calling this function
        if (!this.firstRecord) {
            this.firstRecord = true;
            this.urlHistory.push(this.getCurrentUrl(this.router));
        }

        this.router.events
            .pipe(
                untilDestroyed(this),
                filter(event => event instanceof NavigationEnd),
                pairwise(),
                map(event => {
                    return {
                        previousUrl: (event[0] as ITFNavigationEnd).url,
                        currentUrl:(event[1] as ITFNavigationEnd).url,
                    } as ITFPrevAndCurrentUrl;
                }),
            )
            .subscribe((response: ITFPrevAndCurrentUrl) => {

                // Update current and previous url
                this.previousUrl = response.previousUrl;
                this.currentUrl = response.currentUrl;

                // Update url history
                this.urlHistory = [...this.urlHistory, response.currentUrl];

                // Broadcast new value of current and previous url value
                this.subjectPrevAndCurrUrl.next(response);
            });
    }

    public getCurrentUrl(router: Router): string {
        return router.url;
    }

    public getUrlHistory(): string[] {
        return this.urlHistory;
    }
}

App Root Module

import { NgModule } from "@angular/core";
import { BrowserModule } from "@angular/platform-browser";
import { AppComponent } from "./app.component";

@NgModule({
    declarations: [AppComponent],
    imports: [
        BrowserModule
    ],
    providers: [NavigationService],
    bootstrap: [AppComponent]
})
export class AppModule {
}

Now, you can use the following methods and variables from the Navigation service:

1. currentUrl: to get current URL of the page
2. previousUrl: to get previous URL of the page
3. getHistory(): to get all of the URLs that have been navigated so far
4. prevAndCurrUrl$: to observe the current and previous URLs on each navigation at the moment

Answer 23

The update mentioned above was merged into and released as part of Angular 16. So the solution for this is now much easier:

https://github.com/angular/angular/pull/49235
feat(router): Expose information about the last successful Navigation

https://angular.io/api/router/Router#lastSuccessfulNavigation

lastSuccessfulNavigation: Navigation | null Read-Only

The Navigation object of the most recent navigation to succeed and null if there has not been a successful navigation yet.

Answer 24

All the Above ANSWER will be loads URL multiple times. If user visited any other component also, these code will loads.

So better to use, Service creating concept. https://community.wia.io/d/22-access-the-previous-route-in-your-angular-5-app

This will works well in all versions of Angular. (please Make sure to add it to the providers array in your app.module file! )

Answer 25

I had similar problem when I had wanted to back to previous page. Solution was easier than I could imagine.

<button [routerLink]="['../']">
   Back
</button>

And it returns to parent url. I hope it will help someone ;)