javascript - ngFor 里面 ngFor - Angular 2

Question

我如何在 Angular 2 中使用 *ngFor 遍历多维数组。下面是我使用的 DOM 包装器:

<li *ngFor="let menuName of menuNames" routerLinkActive="active" [ngClass]="{'has-submenu':menuName.submenu?.length>0 }">
    <a href="#" [routerLink]="menuName.route" *ngIf="!menuName.enableSM"> <i class="glyphicon {{menuName.icon}}"></i><span class="nav-label">{{menuName.name}}</span> </a>
    <a href="#" *ngIf="menuName.enableSM"> <i class="glyphicon glyphicon-list-alt"></i> <span class="nav-label">Pages</span> </a>
    <ul class="list-unstyled" *ngIf="menuName.enableSM">
        <li *ngFor="let subMenuName of menuNames['submenu'] let idx = index;"> <a [routerLink]="subMenuName.route">404</a> </li>
    </ul>
</li>

嵌套数组:

menuNames = [{
    name: "Dashboard",
    route: '/home',
    icon: "glyphicon-th-large",
    submenu: [],
    enableSM: false
}, {
    name: "Pages",
    route: '',
    icon: "glyphicon-list-alt",
    submenu: [{
        name: "404",
        route: '/404.html'
    }, {
        name: "Signin",
        route: '/auth/signin'
    }],
    enableSM: true
}];

第二个循环根本不渲染。

Answer 1

您的代码中存在一些小问题，拼写错误。第二个 *ngFor 应该是这样的:

*ngFor="let subMenuName of menuName['submenu']; let idx = index;"

注意它是 menuName 而不是 menuNames 并且在 let idx 之前有一个分号。