与ngFor循环一起动态设置属性

Question

如果索引值匹配，我正在尝试动态设置selected属性。

<select class="form-control" disabled>
  <option *ngFor="let agency of request.agencyList" [attr.selected]="request.agencyIndex == agency">{{agency}}{{request.agencyIndex}}
  </option>
</select>

对象：

this.requests = [{
        agencyList: ['Agency 1', 'Agency 2', 'Agency 3'],
        agencyIndex: 1,
        ...
        }]

但是，它将所有选项selected属性设置为false。

Answer 1

我认为这就是你要找的东西：

<select class="form-control">
   <option *ngFor="let agency of request.agencyList; let index=index;" [selected]="request.agencyIndex == index">
       {{agency}}{{request.agencyIndex}}
   </option>
</select>