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默认,当收到导航到当前URL的请求,Angular路由器会忽略。

<a routerLink="/heroes" routerLinkActive="active">Heroes</a>

重复点击同一链接页面不会刷新。

从Angular 5.1起提供onSameUrlNavigation属性,支持重新加载路由。

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

onSameUrlNavigation有两个可选值:'reload'和'ignore',默认为'ignore'。但仅将onSameUrlNavigation改为'reload',只会触发RouterEvent事件,页面是不会重新加载的,还需配合其它方法。在继续之前,我们启用Router Trace,从浏览器控制台查看一下路由事件日志:

@NgModule({
  imports: [RouterModule.forRoot(routes, {onSameUrlNavigation: 'reload', enableTracing: true})],
  exports: [RouterModule]

可以看到,未配置onSameUrlNavigation时,再次点击同一链接不会输出日志,配置onSameUrlNavigation为'reload'后,会输出日志,其中包含的事件有:NavigationStart、RoutesRecognized、GuardsCheckStart、GuardsCheckEnd、ActivationEnd、NavigationEnd等。

下面介绍刷新当前页面的几种方法:

NavigationEnd

  • 配置onSameUrlNavigation为'reload'
  • 监听NavigationEnd事件
  • 订阅Router Event,在NavigationEnd中重新加载数据,销毁组件时取消订阅:

    export class HeroesComponent implements OnDestroy {
      heroes: Hero[];
      navigationSubscription;
      constructor(private heroService: HeroService, private router: Router) {
        this.navigationSubscription = this.router.events.subscribe((event: any) => {
          if (event instanceof NavigationEnd) {
            this.init();
      init() {
        this.getHeroes();
      ngOnDestroy() {
        if (this.navigationSubscription) {
          this.navigationSubscription.unsubscribe();
    

    这种方式可按需配置要刷新的页面,但代码烦琐。

    RouteReuseStrategy

  • 配置onSameUrlNavigation为'reload'
  • 自定义RouteReuseStrategy,不重用Route
  • 有两种实现方式: 在代码中更改策略:

    constructor(private heroService: HeroService, private router: Router) {
      this.router.routeReuseStrategy.shouldReuseRoute = function () {
        return false;
    

    Angular应用Router为单例对象,因此使用这种方式,在一个组件中更改策略后会影响其他组件,但从浏览器刷新页面后Router会重新初始化,容易造成混乱,不推荐使用。

    自定义RouteReuseStrategy:

    import {ActivatedRouteSnapshot, DetachedRouteHandle, RouteReuseStrategy} from '@angular/router';
    export class CustomReuseStrategy implements RouteReuseStrategy {
      shouldDetach(route: ActivatedRouteSnapshot): boolean {
        return false;
      store(route: ActivatedRouteSnapshot, handle: DetachedRouteHandle | null): void {
      shouldAttach(route: ActivatedRouteSnapshot): boolean {
        return false;
      retrieve(route: ActivatedRouteSnapshot): DetachedRouteHandle | null {
        return null;
      shouldReuseRoute(future: ActivatedRouteSnapshot, curr: ActivatedRouteSnapshot): boolean {
        return false;
    

    使用自定义RouteReuseStrategy:

    @NgModule({
      imports: [RouterModule.forRoot(routes, {onSameUrlNavigation: 'reload'})],
      exports: [RouterModule],
      providers: [
        {provide: RouteReuseStrategy, useClass: CustomReuseStrategy}
    

    这种方式可以实现较为复杂的Route重用策略。

    Resolve

    使用Resolve可以预先从服务器上获取数据,这样在路由激活前数据已准备好。

  • 实现ResolverService
  • 将组件中的初始化代码转移到Resolve中:

    import {Injectable} from '@angular/core';
    import {ActivatedRouteSnapshot, Resolve, RouterStateSnapshot} from '@angular/router';
    import {Observable} from 'rxjs';
    import {HeroService} from '../hero.service';
    import {Hero} from '../hero';
    @Injectable({
      providedIn: 'root',
    export class HeroesResolverService implements Resolve<Hero[]> {
      constructor(private heroService: HeroService) {
      resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<Hero[]> | Observable<never> {
        return this.heroService.getHeroes();
    

    为路由配置resolve:

    path: 'heroes', component: HeroesComponent, canActivate: [CanActivateAuthGuard], resolve: {heroes: HeroesResolverService}
    
  • 修改组件代码,改为从resolve中获取数据
  • constructor(private heroService: HeroService, private route: ActivatedRoute) {
    ngOnInit() {
      this.route.data.subscribe((data: { heroes: Hero[] }) => {
        this.heroes = data.heroes;
    
  • 配置onSameUrlNavigation为'reload'
  • 配置runGuardsAndResolvers为‘always’
  • runGuardsAndResolvers可选值:'paramsChange' 、'paramsOrQueryParamsChange'、'always'

    {path: 'heroes', component: HeroesComponent, canActivate: [CanActivateAuthGuard], resolve: {heroes: HeroesResolverService}, runGuardsAndResolvers: 'always'}
    

    给Router增加时间参数:

    <a (click)="gotoHeroes()">Heroes</a>
    
    constructor(private router: Router) {
    gotoHeroes() {
      this.router.navigate(['/heroes'], {
        queryParams: {refresh: new Date().getTime()}
    

    然后在组件中订阅queryParamMap:

    constructor(private heroService: HeroService, private route: ActivatedRoute) {
      this.route.queryParamMap.subscribe(params => {
        if (params.get('refresh')) {
          this.init();
    

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