Angular 2: TypeError: Cannot read property 'isRouteActive' of undefined in

Question

我正在尝试使用 isRouteActive 函数通过单击其中包含的链接来切换 li 元素的 active class，但它一直给我像 TypeError: Cannot read property 'isRouteActive' of undefined in [isRouteActive(['./Home']) in AppComponent@6:16] 这样的错误。该文件如下所示：

import {Component} from 'angular2/core';
import {ROUTER_DIRECTIVES, RouteConfig, Router } from 'angular2/router';
import {FORM_PROVIDERS, FORM_DIRECTIVES, Control} from 'angular2/common';
import {LoginComponent} from './login.component.js';
import {HomeComponent} from './home.component.js';

@Component({
selector: 'front-page-app',
providers: [ FORM_PROVIDERS ],
directives: [ ROUTER_DIRECTIVES, FORM_DIRECTIVES ],
template: `
<div class="container">
  <div class="header clearfix">
    <nav>
      <ul class="nav nav-pills pull-right">
        <li #homeLink role="presentation" 
            [class.active]="isRouteActive(['./Home'])">
        <a [routerLink]="['./Home']">Home</a>
        </li>
        <li #loginLink role="presentation" 
            [class.active]="isRouteActive(['./Login'])">
        <a [routerLink]="['./Login']">Login</a>
        </li>
      </ul>
    </nav>
    <h3 class="text-muted">Fomoapp</h3>
  </div>
</div> <!-- /container -->
<router-outlet></router-outlet>
`
})

@RouteConfig([
{ path: '/login', component: LoginComponent, name: 'Login' },
{ path: '/home', component: HomeComponent, name: 'Home' },
{ path: '/', redirectTo: ['Home'] }
])
export class AppComponent { 
public isRouteActive(route) {
    return this.router.isRouteActive(this.router.generate(route))
}
}

我尝试了多种路径，例如“/home”、“#/home”、“/Home”、“./Home”，'Home' 但其中 none 行得通。错误可能与什么有关？以及如何实际调试这种情况？

Answer 1

刚刚发布了问题，终于找到了答案：忘记输入constructor并提供Router。因此，工作版本更改了 export class Appcomponent 部分，看起来如下所示：

export class AppComponent { 
    constructor(private router: Router) {
    }

    public isRouteActive(route) {
        return this.router.isRouteActive(this.router.generate(route))
    }
}

另见 the link。

Answer 2

我会按照中的建议在 <a> 元素上使用 router-link-active。

干杯，

大卫

Angular 2: TypeError: Cannot read property 'isRouteActive' of undefined in

Angular 2: TypeError: Cannot read property 'isRouteActive' of undefined in

angular

angular2-routing