Angular反应表单提交并清除验证

Question

我有一个反应式

 <form [formGroup]="secondFormGroup">
      <ng-template matStepLabel>enter items</ng-template>
      <div style="display: flex; flex-direction: column;">
        <mat-form-field>
          <input matInput type="text" placeholder="category"  [(ngModel)]="newItem.CategoryName" formControlName="category"
          />
        </mat-form-field>
        <mat-form-field>
          <input matInput type="text" placeholder="sub category"  [(ngModel)]="newItem.SubCategoryName" formControlName="subCategory"
          />
        </mat-form-field>
        <mat-form-field>
          <input matInput type="text" placeholder="product"  [(ngModel)]="newItem.ProductName" formControlName="name"/>
        </mat-form-field>
        <mat-form-field>
          <input matInput  [(ngModel)]="newItem.Amount" type="number" min="0" placeholder="amount" formControlName="amount"
          />
        </mat-form-field>
        <mat-form-field>
          <input matInput  [(ngModel)]="newItem.Price" type="number" min="0" placeholder="price" formControlName="price"
          />
        </mat-form-field>
        <button mat-raised-button color="primary" (click)="AddNewProduct(newItem)" style="float: left; align-self: flex-end;">submit</button>
      </div>
    </form>

我这样初始化：

 this.secondFormGroup = this._formBuilder.group({
  category: ['', Validators.required],
  subCategory: ['', Validators.required],
  name: ['', Validators.required],
  amount: ['', Validators.required],
  price: ['', Validators.required]
});

单击sumbit后，我调用此方法：

AddNewProduct(newProduct) {
if (this.secondFormGroup.valid) {
  //add product
  this.secondFormGroup.reset();
 } 
}

添加产品后，我清除表格。但是，一旦清除了表单，就会触发验证错误。我希望仅在用户单击提交并且表单无效时才显示验证错误，而不是在提交后清除表单时才显示验证错误。

我怎样才能解决这个问题？

Answer 1

The issue seems to be that the form is marked as submitted after reset is called. If the form is marked as submitted, regardless of whether or not its pristine, the errors will be highlighted.

You'll need to call resetForm instead, which is on the FormGroupDirective:

@ViewChild(FormGroupDirective) formGroupDirective: FormGroupDirective;

this.formGroupDirective.resetForm();

Secondly, you'll need to wrap it in a setTimeout with a timeout of 0, so that the form is submitted before it resets.

setTimeout(() => this.formGroupDirective.resetForm(), 0)

I've tested this in a StackBlitz, and it all seems to work:

https://stackblitz.com/edit/angular-l6xq1d?file=src%2Fapp%2Fapp.component.ts