Angular 2 rc4：无法从表单中获取值

Question

这是我的代码的一部分。

<form (ngSubmit)="onSubmit(f)" #f="ngForm">
            <label for="city">City</label>
            <input ngControl="cityName" type="text" id="city">
            <button type="submit">Add City</button>
</form>

export class SearchCity {
   onSubmit(form: ControlGroup){
         console.log(form.value.cityName);
   }

它显示Undefined，我如何获得cityName的价值？

Answer 1

您必须添加#cityName="ngForm"才能获得cityName值，如下所示。

https://plnkr.co/edit/CvNwKb8lZtIZHcg05lgS?p=preview

<form (ngSubmit)="onSubmit(f.value)" #f="ngForm">  
                <label for="city">City</label>
                <input ngControl="cityName" #cityName="ngForm" type="text" id="city">  
                //added #cityName="ngForm" as you are dealing with ngControl

                <button type="submit">Add City</button>
</form>


onSubmit(myForm){
   console.log(myForm.cityName);
}