我有一个选择选项,我想给占位符说“选择一个类别”
<form role="form" class="form form-horizontal" (ngSubmit)="onSubmit()" #form="ngForm" ngNativeValidate>
<div class="form-group row">
<div class="col-xl-4 col-lg-6 col-md-12">
<fieldset class="form-group">
<label for="customSelect">Categories:</label>
<select class="custom-select d-block w-100" id="Category" [(ngModel)]="Category" name="Category" required>
<option value=" ">Select one category </option>
<option *ngFor="let item of myBusinessList" [value]="item.id">{{item.name}}</option>
</select>
</fieldset>
</div>
</div>
<button type="submit" class="btn btn-raised btn-danger">Save</button>
</form>
如果我删除[ngModel]然后它的工作原理.如果我写
<option value="undefined" selected>Select one category </option>
然后它认为是价值之一.我必须确保有位置,并且还需要选择其中一个值
解决方法
您可以使用[value] =“”选择隐藏
我在Stackblitz上创建了一个demo
<form role="form" class="form form-horizontal" (ngSubmit)="onSubmit()" #form="ngForm" ngNativeValidate>
<div class="form-group row">
<div class="col-xl-4 col-lg-6 col-md-12">
<fieldset class="form-group">
<label for="customSelect">Categories:</label>
<select class="custom-select d-block w-100" id="Category" [(ngModel)]="Category" name="Category" required placeholder="d.ff">
<option hidden [value]="" selected>Select one category </option>
<option *ngFor="let item of myBusinessList" [value]="item.id">{{item.name}}</option>
</select>
</fieldset>
</div>
</div>
<button type="submit" class="btn btn-raised btn-danger">Save</button>
</form>
