Javascript 角度表单验证，在HTML上迭代时访问表单控件

我有一个答案选项为单选按钮字段的问题列表。我从JSON文件中得到了这些问题和答案，所以我在HTML上对其进行迭代，并动态地为formControlName赋值。我的问题是如何在迭代控制值时进行验证

*ngIf="cricketForm.control.get('ques{{i}}').invalid" 

*ngIf="cricketForm.control.get('ques{{i}}').invalid" 

这给了我一个错误。如何以正确的方式进行

目前验证工作不正常

html文件：

<form [formGroup]="cricketForm">
  <div *ngFor = "let user of userJson; let i =index ">
    <div class="label1" for="NameId">{{user.question}}</div>
    <mat-radio-group formControlName="ques{{i+1}}" aria-label="Select an option">
      <div *ngFor = "let option of user.options; let j =index">
        <mat-radio-button  [value]=j>{{option}}</mat-radio-button>
      </div>
    </mat-radio-group>


  <div class="invalid-feedback" *ngIf="cricketForm.control.get('ques{{i}}').invalid" >This field is required</div>
  </div>
    <button (click)="onSubmit()">Submit</button>
    <button (click)="onReset()">Reset</button>
</form>

示例JSON数据：

[
{"question": "Who Was The First Indian To Hit A Test Century?", "options":["Lala Amarnath","Kapil Dev", "Sunil Gavaskar"],"ans":"Lala Amarnath"},
{"question":"Who Won The Inaugural Asia Cup Championship?","options":["Pakistan","Sri Lanka", "India"],"ans":"India"},
{"question":"Who Was Australia’s First Captain?","options":["F.S.Jackson"
,"D.W. Gregory", "Tony Lewis"],"ans":"D.W. Gregory"},
{"question":" When And Where Was The First Ranji Trophy Match Played?","options":["kolkata"
,"Mumbai", "Chennai"],"ans":"Chennai"}
]

---

您有一个语法错误。一定是

*ngIf="cricketForm.get('ques'+(i+1)).invalid"

看你的

注意：我认为您必须尝试使用Formarray重新思考您的代码。方法很简单

<form formGroup="formArray">
  <div *ngFor = "let control of formArray.controls; let i =index ">
    <div class="label1" for="NameId">{{userJson[i].question}}</div>
    <mat-radio-group [formControl]="control" aria-label="Select an option">
      <div *ngFor = "let option of userJson[i].options; let j =index">
        <mat-radio-button  [value]=j>{{option}}</mat-radio-button>
      </div>
    </mat-radio-group>
  <div class="invalid-feedback" *ngIf="control.invalid" >This field is required</div>
  </div>
    <button (click)="onSubmit()">Submit</button>
    <button (click)="onReset()">Reset</button>

</form>

---

你能提供JSON数据吗？看看我的库ngx ez，它完成了表单验证的所有繁重工作。在@Sonam的一个演示中，每次只有四个问题吗？@PrashantPimpale我要回答四个问题。如果没有问题，那么我必须增加ts文件中的表单控制。你有更好的解决方案吗？创建动态表单Hanks Eliseo！我一定会应用你的建议，使用FormArray1作为表单数组！

<form formGroup="formArray">
  <div *ngFor = "let control of formArray.controls; let i =index ">
    <div class="label1" for="NameId">{{userJson[i].question}}</div>
    <mat-radio-group [formControl]="control" aria-label="Select an option">
      <div *ngFor = "let option of userJson[i].options; let j =index">
        <mat-radio-button  [value]=j>{{option}}</mat-radio-button>
      </div>
    </mat-radio-group>
  <div class="invalid-feedback" *ngIf="control.invalid" >This field is required</div>
  </div>
    <button (click)="onSubmit()">Submit</button>
    <button (click)="onReset()">Reset</button>

</form>

this.formArray=new FormArray(
    this.userJson.map(
      ()=>new FormControl(null,Validators.required))
);