Cart view里的form控件:
<form [formGroup]="checkoutForm" (ngSubmit)="onSubmit(checkoutForm.value)">
<div>
<label for="name">
Name
</label>
<input id="name" type="text" formControlName="name">
</div>
<div>
<label for="address">
Address
</label>
<input id="address" type="text" formControlName="address">
</div>
<button class="button" type="submit">Purchase</button>
</form>
最后生成的html page:
如果Component的模板实现里,form的属性formGroup,即中括号属性后面的值checkoutForm2实际上不存在,那么在页面渲染之前会报错:ERROR Error: formGroup expects a FormGroup instance. Please pass one in.