Angular 4/5 ng对于意外的索引错误

Bir*_*Dad 0 arrays iteration typescript angular

我正在尝试列出输入,我无法编译ngFor.

<div *ngFor="let q of questions; let i = index" class="col-3">
  <div class="group">
    <input [(ngModel)]="q" [class.ng-not-empty]="q.length > 0">
    <span class="bar"></span>
    <label>Question {{i}}</label>
  </div>
</div>
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我的定义如下:

questions: string[];
constructor() {
  this.questions = ['blah', 'blah', 'blah'];
}
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我得到的错误是:

ERROR in : Error: Cannot assign to a reference or variable!
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如果我删除了它的索引定义,我已经尝试了以下所有方法:

*ngfor="let q of questions | index as i"
*ngfor="let q of questions; index as i"
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fil*_*rak 6

您无法使用,[(ngModel)]="q"因为您尝试分配HTML中的本地变量(在本例中let q)

试试这个:

[(ngModel)]="questions[i]";
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