我在验证 Angular 表单时显示消息时出错

Question

我正在创建一个 Angular 表单，在验证时，我试图在字段未填写时显示消息，因此我在 span 标记中使用了 ng-for 但出现错误

html->

<div class="form-group">
    <input type="text" formControlName='fname' placeholder="First Name">
    <span *ngFor="signupForm.control['fname'].haserror(required)"> Enter your Name </span>
</div>

错误-

Can't bind to 'ngFor' since it isn't a known property of 'span'. ("m-group">
       <input type="text" formControlName='fname'  placeholder="First Name">
       <span [ERROR ->]*ngFor="signupForm.control['fname'].haserror(required)"> Enter your Name </span>
      </div>

Answer 1

使用*ngIf代替*ngFor

Stackblitz Demo

<span *ngIf="signupForm.get('fname').hasError('required')"> Enter your Name </span>

我在验证 Angular 表单时显示消息时出错

I am Getting error while showing a message while validating Angular form

angular-ng-if

ngfor

angular