Angular2:如何知道*ngFor上的迭代器数量

Question

我想知道ngFor上的迭代器数量,以便基于我可以显示或隐藏的元素,例如我想这样做,如果迭代器的数量到达它应该停止迭代.到目前为止,整个模板是:

<p *ngIf = "heros2.length > 3"> 
    there are two many users
    </p>
    <div *ngIf = "heros2.length == 3">
    <ul>
    <li *ngFor = 'let hero1 of heros2'>
    there are many users
    {{hero1.name}}
    </li>
    </ul>
    </div>

Answer 1

这是语法:

*ngFor="let hero1 of heroes2; let i=index"

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