生产版本上的 Angular4 编译错误："Property controls does not exist on type AbstractControl"

Question

我的代码在开发模式下构建并完美地运行。当我为生产构建时，我会在此行上获得此错误：

        <div *ngFor="let child of form.controls.emailsArray.controls; let i=index">

形式是这样构建的：

  public form: FormGroup;
  private control: FormArray;
  private emailsModel = { emails: ['','','','','']}  // the model, ready to hold the emails
  private fb : FormBuilder;
  constructor() {}
  ngOnInit() {
    this.fb = new FormBuilder;
        this.form = this.fb.group({
      emailsArray: this.fb.array([])
    });
    this.control = <FormArray>this.form.controls['emailsArray'];
    this.patch();    
  }
  private patch(): void {
    // iterate the object model and extra values, binding them to the controls
    this.emailsModel.emails.forEach((item) => {
      this.control.push(this.patchValues(item));
    })
  }
  private patchValues(item: string): AbstractControl {
    return this.fb.group({
      email: [item, Validators.compose([emailValidator])] 
    })
  }

那么如何在html中引用这些子控制器？

注意：与此问题类似，除了我的错误在HTML中发生，而不是打字稿。

Answer 1

我不确定这是否是好练习，但是将html更改为有效：

<div *ngFor="let child of form.controls.emailsArray['controls']; let i=index">

Answer 2

对我而言，这解决了：

更改

meeting.controls.schedule.controls['scheduleEnd']

to

meeting.controls.schedule['controls'].frequency