update (2.0.0 final)

(somepath/:someparam/someotherpath) you can subscribe to them using _router.queryParams.subscribe(...):

export class HeroComponent implements OnInit {
  constructor(private _activatedRoute: ActivatedRoute, private _router:Router) {
    _activatedRoute.queryParams.subscribe(
      params => console.log('queryParams', params['st']));

original

If you want queryParams instead of route params (somepath/:someparam/someotherpath) you can subscribe to them using _router.routerState.queryParams.subscribe(...):

export class HeroComponent implements OnInit {
  constructor(private _activatedRoute: ActivatedRoute, private _router:Router) {
    _router.routerState.queryParams.subscribe(
      params => console.log('queryParams', params['st']));

Plunker example


I was struggling with the same problem for a long time. The answer is tricky, in the documentation it was stated:

ActivatedRoute: A service that is provided to each route component that contains route specific information such as route parameters, static data, resolve data, global query params, and the global fragment. This is mentioned in here

The trick answer is 'route component', that means ActivatedRoute will work only on components that are routed. In other words only components described in the routing table.

> Reading the obfuscating official documentation here. It mentions 'route associated with a component loaded in an outlet'. We can only guess what is an outlet...

I wrote a little investigative code to research this problem in stand alone app.module.ts:

import { Component, NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { RouterModule, Routes, ActivatedRoute } from '@angular/router';

@Component({
  selector: 'comp1',
  template: `<h4>comp1 works</h4>`,
})
export class Comp1 { }

@Component({
  selector: 'comp2',
  template: `<h4>comp2 works</h4>`,
})
export class Comp2 { }

@Component({
  selector: 'fail',
  template: `<div>Wrong URL:{{url | json}}</div> <h4>Failure page works</h4>`,
})
export class Fail {
  private url: any;
  constructor(public activeRoute: ActivatedRoute) {
    this.url = activeRoute.snapshot.url
  };

}

@Component({
  selector: 'app-root',
  template: `<div>Base URL:{{url | json}}</div> <router-outlet></router-outlet>`,
})
export class App {
  private url: any;
  constructor(public activeRoute: ActivatedRoute) {
    this.url = activeRoute.snapshot.url
  };
}

const appRoutes: Routes = [
  { path: '1', component: Comp1 },
  { path: '2', component: Comp2 },
  { path: '**', component: Fail }
];

@NgModule({
  imports: [BrowserModule, RouterModule.forRoot(appRoutes)],
  declarations: [App, Comp2, Comp1, Fail],
  bootstrap: [App]
})
export class AppModule { }

Try running the module for the following URI:

  • http://localhost:4200/2
  • http://localhost:4200/1
  • http://localhost:4200/a/b/c

Good luck, hope the code is demonstrative.


check angular documentation, its all there: https://angular.io/docs/ts/latest/guide/router.html

constructor(
  private route: ActivatedRoute,
  private router: Router,
  private service: HeroService) {}

    ngOnInit() {
      this.sub = this.route.params.subscribe(params => {
         let id = +params['id']; // (+) converts string 'id' to a number
         this.service.getHero(id).then(hero => this.hero = hero);
       });