我会这样写:

ngOnInit() {
this.routed = this.router.events.map( event => event instanceof NavigationStart )
  .subscribe(() => {
  } );
}

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

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);
            }
        });

   }
}

路由器3.0.0-beta。2应该是

this.router.events.subscribe(path => {
  console.log('path = ', path);
});

只需在AppRoutingModule上进行更改

@NgModule({
imports: [RouterModule.forRoot(routes, { scrollPositionRestoration: 'enabled' })],
  exports: [RouterModule]
})

以以下方式捕获路由更改事件…

import { Component, OnInit, Output, ViewChild } from "@angular/core";
import { Router, NavigationStart, NavigationEnd, Event as NavigationEvent } from '@angular/router';

@Component({
    selector: "my-app",
    templateUrl: "app/app.component.html",
    styleUrls: ["app/app.component.css"]
})
export class AppComponent {

    constructor(private cacheComponentObj: CacheComponent,
        private router: Router) {

        /*  Route event types
            NavigationEnd
            NavigationCancel
            NavigationError
            RoutesRecognized
        */
        router.events.forEach((event: NavigationEvent) => {

            //Before Navigation
            if (event instanceof NavigationStart) {
                switch (event.url) {
                case "/app/home":
                {
                    //Do Work
                    break;
                }
                case "/app/About":
                {
                    //Do Work
                    break;
                }
                }
            }

            //After Navigation
            if (event instanceof NavigationEnd) {
                switch (event.url) {
                case "/app/home":
                {
                    //Do Work
                    break;
                }
                case "/app/About":
                {
                    //Do Work
                    break;
                }
                }
            }
        });
    }
}

@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。