How to go back to last page when having child router?

Please see comments in code for details. Thanks

export class OneProductComponent {
  prevUrlPath:string = '';

  constructor(private _router: Router) {}

  routerOnActivate(next:ComponentInstruction, prev:ComponentInstruction) {
    this.prevUrlPath = prev.urlPath;
  }

  goBack() {
    // I have to manually add "products/" here, but if I need 
    // go back to root home page. Then I shouldn't add "products/" here.
    // Is there a smart way to to this?
    this._router.navigateByUrl(`products/${this.prevUrlPath}`);
  }
}

Solution

The angular 2 documentation on routing suggests that you use the window object instead https://angular.io/docs/ts/latest/tutorial/toh-pt5.html#!#find-our-way-back

goBack() {
  window.history.back();
}