Angular 反应式表单选择标记验证

我正在对选择标记验证进行反应式表单验证，但其验证不起作用。这是一个基本的反应式表单验证，我已经对其他字段进行了验证，它们正在工作，但select标记（状态输入字段）上的一个验证不工作

html文件

<div class="container">
  <form [formGroup]="info" (ngSubmit)="onSubmit">
    <h1>Info</h1>
    <div>
      <label>First Name</label>
      <input
        type="text"
        formControlName="firstName"
        class="form-control"
        [ngClass]="{ 'is-invalid': f.firstName.touched && f.firstName.errors }"
      />
      <div
        *ngIf="f.firstName.touched && f.firstName.errors"
        class="alert alert-danger"
      >
        <div *ngIf="f.firstName.errors.required">First Name is required</div>
        <div *ngIf="f.firstName.errors.minlength">Minimum 3 characters</div>
        <div *ngIf="f.firstName.errors.maxlength">Maximum 10 characters</div>
        <div *ngIf="f.firstName.errors.pattern">Only alphabets</div>
      </div>
    </div>

    <div>
      <label>Last Name</label>
      <input
        type="text"
        formControlName="lastName"
        class="form-control"
        [ngClass]="{'is-invalid':f.lastName.touched && f.lastName.errors}"
      />
      <div *ngIf="f.lastName.touched && f.lastName.errors">
        <div *ngIf="f.lastName.errors.required">Last name required</div>
        <div *ngIf="f.lastName.errors.minlength">Minimum 3 characters</div>
        <div *ngIf="f.lastName.errors.maxlength">Minimum 10 characters</div>
      </div>
    </div>

    <div>
      <label for="">Gender</label>

      <input
        type="radio"
        formControlName="gender"
        class="form-control"
        value="male"
      /><span>male</span>
      <input
        type="radio"
        formControlName="gender"
        class="form-control"
        value="female"
      /><span>female</span>
      <input
        type="radio"
        formControlName="gender"
        class="form-control"
        value="other"
      /><span>other</span>

      <div>
        <div *ngIf="f.gender.touched && f.gender.errors">
          <div>Gender required</div>
        </div>
      </div>
    </div>

    <div>
      <label for="state">State</label>
      <select id="state" formControlName="state" class="form-control" 
      [ngClass]="{'is-invalid':f.state.touched && f.state.errors}">
        <option value=""></option>
        <option value="Delhi">Delhi</option>
        <option value="UP">UP</option>
        <option value="Karnataka">Karnataka</option>
        <option value="Bihar">Bihar</option>
        <div>
        <div *ngIf="f.state.errors.touched && f.state.errors">
          <div *ngIf="f.state.errors.required">state required</div>

        </div></div>
      </select>
    </div>

    <div>
      <label for="qualification">qualification</label>
      <input
        type="checkbox"
        formControlName="qualification"
        class="form-control"
        value="Graduate"
      /><span>Graduate</span>
      <input
        type="checkbox"
        formControlName="qualification"
        class="form-control"
        value="Post Graduate"
      /><label>Post Graduate</label>

      <div>
        <div *ngIf="f.qualification.touched && f.qualification.errors">
          <div>qualification required</div>
        </div>
      </div>
    </div>
    <div>
      <button type="submit" (click)="onSubmit" [disabled]="info.invalid">
        submit
      </button>
    </div>
  </form>
</div>

---

您使用了

f.state.errors.toucted

它必须是

f.state.toucted

  <div *ngIf="f.state.touched && f.state.errors">
              <div *ngIf="f.state.errors.required">state required</div>

            </div></div>

---

我已经创建了一个包含所有更改的应用程序。

您能提供stackblitz演示吗？@sudeep若这对您有效，请选择它并给出答案。@sudeep stackblitz链接有问题，您现在可以访问它

  <div *ngIf="f.state.touched && f.state.errors">
              <div *ngIf="f.state.errors.required">state required</div>

            </div></div>

  <div>
      <label for="state">State</label>
      <select id="state" formControlName="state" class="form-control" 
      [ngClass]="{'is-invalid':f.state.touched && f.state.errors}">
         <option value=""></option>
        <option value="Delhi">Delhi</option>
        <option value="UP">UP</option>
        <option value="Karnataka">Karnataka</option>
        <option value="Bihar">Bihar</option>

      </select>
         <div>
        <div *ngIf="f.state.touched && f.state.errors">
          <div *ngIf="f.state.errors.required">state required</div>

        </div></div>
    </div>