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
            }
        });
   }
}

this.router.events.subscribe((event) => {
  if (event instanceof NavigationStart) {
    this.showProgressBar = true
  } else if (event instanceof NavigationEnd) {
    this.showProgressBar = false
  }
  else if (event instanceof NavigationCancel) {
    this.showProgressBar = false
  }
})

您可以在任何事件路由状态下订阅

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: '/'})]);

@Ludohen的回答很好，但如果你不想使用instanceof，请使用下面的方法

this.router.events.subscribe(event => {
  if(event.constructor.name === "NavigationStart") {
    // do something...
  }
});

通过这种方式，您可以检查当前事件名称作为字符串，如果事件发生，您可以执行您计划的函数要执行的操作。

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
            }
        });
   }
}

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);
            }
        });

   }
}