属性 'controls' 在类型 'AbstractControl' 上不存在。对于数组元素?

Property 'controls' does not exist on type 'AbstractControl'. for array elements?

组件代码为:

this.orderForm = this.formBuilder.group({
      items: this.formBuilder.array([])
});

表格是:

<form [formGroup]="orderForm">
<div
      class="form-group"
      formArrayName="items"
      *ngFor="let item of orderForm.get('items').controls; let i = index"
    >
</div>
</form>

我收到错误消息:

Property 'controls' does not exist on type 'AbstractControl'.

我该如何解决:

像这样尝试

get items() : FormArry {
 return this.orderForm.get('items') as FormArray
}

模板

<form [formGroup]="orderForm">
  <div formArrayName="items">
    <div class="form-group" *ngFor="let item of items.controls; let i = index">
     ...
    </div>
  </div>
</form>