routerlink 更改时不调用 Angular 2 ngOnInit

Question

我有一个菜单栏，其中包含从 express api 加载的菜单列表，每个菜单都引用了一个页面，该页面有一个别名，该别名将是该页面的 URL我试图在单击菜单时加载页面，它已完成，但仅在我刷新页面时这是我的菜单代码

export class MenuList implements OnInit {

menus:Menu[];
menu:Menu;
page:Page;

constructor(private router:Router,
            private menuService:MenuService) {
}

getMenus():void {
    this.menuService.getMenus()
        .subscribe(
            menus => this.menus = menus, //Bind to view
            err => {
                // Log errors if any
                console.log(err);
            }
        );
}

getPage(id):void {
    this.menuService.getPage(id)
        .subscribe(
            page => this.page = page, //Bind to view
            err => {
                // Log errors if any
                console.log(err);
            });
}

ngOnInit():void {
    this.getMenus();
}

这是我的模板菜单

<div class="container-fluid">
    <!-- Brand and toggle get grouped for better mobile display -->
    <div class="navbar-header">
        <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false">
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
        </button>
    </div>

    <!-- Collect the nav links, forms, and other content for toggling -->
    <div class="collapse navbar-collapse" id="navbar"  style="background-color: #97455f">
        <div class="navv">
            <ul *ngFor="let menu of menus">
                <li class="col-lg-1 col-md-1 col-xs-12 col-sm-12"><a [routerLink]="[menu.page.alias]">{{menu.title}}</a></li>


            </ul>
        </div>
    </div>

</div><!-- /.navbar-collapse -->

我认为问题出在我的页面组件的 ngOnInit 上，它没有被调用

    @Component({
    selector: 'page',
    templateUrl: './page.component.html'
})
export class PageComponent implements OnInit {
    alias: string;
    page:Page;

    constructor(private router:Router,
                private route: ActivatedRoute,
                private pageService:PageService) {

        this.route.params.subscribe(
            (params : Params) => {
                this.alias = params["alias"];
                console.log(this.alias)
            }
        );
    }




    ngOnInit():void {
        debugger;
        this.pageService.getPage(this.alias).subscribe(page => {
            this.page = page;
            console.log(this.page);
        });
    }

}

这是我的页面模板

    <p *ngIf="page" [innerHTML]="page.content" ></p>

这是我的应用路由代码

const routes: Routes = [
    { path: '', redirectTo: '/home', pathMatch: 'full' },
    { path: ':alias', component: PageComponent },
    { path: 'archived',  component: ArchivedComponent },
    { path: 'home',  component: HomeComponent },
    { path: 'menu',  component: MenuList },
    { path: 'detail/:id', component: ActualiteDetailComponent },
    { path: 'contact',  component: ContactComponent },

];

@NgModule({
    imports: [ RouterModule.forRoot(routes) ],
    exports: [ RouterModule ]
})
export class AppRoutingModule {}

这是我的应用组件

@Component({
  selector: 'my-app',
  template: `
    <menu-list></menu-list>
    <hr>
`

})
export class AppComponent {

}

Home of application with the menu bar

Answer 1

这是 Gunter 所谈论内容的代码示例:

  constructor(private route: ActivatedRoute) { }

  ngOnInit() {
     this.route.params.subscribe(
     params => {
        let id= +params['id'];
        this.getProduct(id);
     });
  }

此代码监视参数的变化并执行箭头函数内的任何代码。