在Angular 8中，你应该这样做。router.events。订阅((事件:事件)=> {})

例子:

import { Component } from '@angular/core'; 
import { Router, Event } from '@angular/router';
import { NavigationStart, NavigationError, NavigationEnd } from '@angular/router';

@Component({
    selector: 'app-root',
    template: `<router-outlet></router-outlet>`
})
export class AppComponent {

    constructor(private router: Router) {
        //Router subscriber
        this.router.events.subscribe((event: Event) => {
            if (event instanceof NavigationStart) {
                //do something on start activity
            }

            if (event instanceof NavigationError) {
                // Handle error
                console.error(event.error);
            }

            if (event instanceof NavigationEnd) {
                //do something on end activity
            }
        });
   }
}

以上大多数解决方案是正确的，但我面临的问题是这个发射多次'导航发射'事件。当我改变任何路由时，此事件被触发。所以hear是Angular 6的完整解决方案。

import { Subscription } from 'rxjs/Subscription';
import 'rxjs/add/operator/do';
import 'rxjs/add/operator/filter';    

export class FooComponent implements OnInit, OnDestroy {
   private _routerSub = Subscription.EMPTY;
   constructor(private router: Router){}

   ngOnInit(){
     this._routerSub = this.router.events
      .filter(event => event instanceof NavigationEnd)
      .subscribe((value) => {
         //do something with the value
     });
  }

  ngOnDestroy(){
   this._routerSub.unsubscribe();
  }
} 

下面的方法可以帮你解决棘手的问题。

// in constructor of your app.ts with router and auth services injected
router.subscribe(path => {
    if (!authService.isAuthorised(path)) //whatever your auth service needs
        router.navigate(['/Login']);
    });

不幸的是，这在路由过程中比我想要的晚些时候重定向。在重定向之前调用原始目标组件的onActivate()。

你可以在目标组件上使用@CanActivate装饰器，但这是a)不集中的，b)不能从注入的服务中受益。

如果有人能提出一种更好的方法，在路由提交之前对其进行集中授权，那就太好了。我相信一定有更好的办法。

这是我当前的代码(我如何改变它来监听路由变化?):

import {Component, View, bootstrap, bind, provide} from 'angular2/angular2';
import {ROUTER_BINDINGS, RouterOutlet, RouteConfig, RouterLink, ROUTER_PROVIDERS, APP_BASE_HREF} from 'angular2/router';    
import {Location, LocationStrategy, HashLocationStrategy} from 'angular2/router';

import { Todo } from './components/todo/todo';
import { About } from './components/about/about';

@Component({
    selector: 'app'
})

@View({
    template: `
        <div class="container">
            <nav>
                <ul>
                    <li><a [router-link]="['/Home']">Todo</a></li>
                    <li><a [router-link]="['/About']">About</a></li>
                </ul>
            </nav>
            <router-outlet></router-outlet>
        </div>
    `,
    directives: [RouterOutlet, RouterLink]
})

@RouteConfig([
    { path: '/', redirectTo: '/home' },
    { path: '/home', component: Todo, as: 'Home' },
    { path: '/about', component: About, as: 'About' }
])

class AppComponent {    
    constructor(location: Location){
        location.go('/');
    }    
}    
bootstrap(AppComponent, [ROUTER_PROVIDERS, provide(APP_BASE_HREF, {useValue: '/'})]);

对于Angular 7，应该这样写:

this.router.events。订阅((事件:事件)=> {})

具体示例如下:

import { Component } from '@angular/core'; 
import { Router, Event, NavigationStart, NavigationEnd, NavigationError } from '@angular/router';

@Component({
    selector: 'app-root',
    template: `<router-outlet></router-outlet>`
})
export class AppComponent {

    constructor(private router: Router) {

        this.router.events.subscribe((event: Event) => {
            if (event instanceof NavigationStart) {
                // Show loading indicator
            }

            if (event instanceof NavigationEnd) {
                // Hide loading indicator
            }

            if (event instanceof NavigationError) {
                // Hide loading indicator

                // Present error to user
                console.log(event.error);
            }
        });

   }
}

如果您只是想检查路由/查询参数更改，如localhost:4200/users/1?编辑=1到localhost:4200/users/2?Edit =0你可以像下面这样使用可观察的参数。

import { ActivatedRoute, Params } from '@angular/router';
export class SomeClass implements OnInit {

paramFromRoute;

constructor(private route: ActivatedRoute) { }

ngOnInit() {
  this.paramFromRoute = this.route.snapshot.params['paramName']; // this one is required for getting it first time

  this.route.params.subscribe((params:Params)=>{
    this.paramFromRoute =  params['paramName'] // whenever route is changed, this function will triggered.
  });
  // for queryParams you can subscribe to this.route.queryParams
 }   
}

在Angular 2中，你可以订阅(Rx事件)一个Router实例。 你可以这样做

class MyClass {
  constructor(private router: Router) {
    router.subscribe((val) => /*whatever*/)
  }
}

编辑(从rc.1开始)

class MyClass {
  constructor(private router: Router) {
    router.changes.subscribe((val) => /*whatever*/)
  }
}

编辑2(从2.0.0开始)

请参见:路由器。活动文档

class MyClass {
  constructor(private router: Router) {
    router.events.subscribe((val) => {
        // see also 
        console.log(val instanceof NavigationEnd) 
    });
  }
}