angular - Angular 输入[类型=数字]中的验证错误？

Question

我在尝试验证 input[type=number] 时遇到一个奇怪的问题在 Angular 7 中，希望有人能提供帮助。

    <input class="form-control" type="number" name="entranceFee" min="0" [(ngModel)]="entranceFee" #entranceFee="ngModel" pattern="\\d+" [ngClass]="{ 'is-invalid': entranceFee.touched && entranceFee.invalid }" >
    <div *ngIf="entranceFee.invalid && entranceFee.touched" class="invalid-feedback">
        <div *ngIf="entranceFee.errors.pattern">Only numbers are permitted</div>
        <div *ngIf="entranceFee.errors.min">Value cannot be smaller than '0'</div>
    </div>

输入仅接受 numbers >= 0 。但每当我输入数字值(0-9)时，表单就会变得无效。为什么？当我在ngAfterViewChecked()中的控制台中输出ngModel时数值已写入模型。那么我怎样才能验证这个表格呢？验证器或我的头脑中是否存在错误？

使用响应式(Reactive)表单和/或 input[type=text] 实现此代码时也会发生同样的情况

Answer 1

尝试一下:

<input 
  class="form-control" 
  type="number" 
  name="entranceFee"
  #entranceFee="ngModel"  
  [(ngModel)]="entranceFee.value"
  pattern="^[+]?([0-9]+(?:[\.][0-9]*)?|\.[0-9]+)$"
  [ngClass]="{ 'is-invalid': entranceFee.touched && entranceFee.invalid }" >

<div *ngIf="entranceFee.invalid && entranceFee.touched" class="invalid-feedback">
  <div *ngIf="entranceFee.errors.pattern">Only numbers are permitted</div>
  <div *ngIf="entranceFee.errors.min">Value cannot be smaller than '0'</div>
</div>

<小时/>

Here's a Working Sample StackBlitz for your ref.

<小时/>

正则表达式礼貌 - This Answer