Angular 2 中的提交与 ngSubmit

html
<form (ngSubmit)="onSubmit()">
  <!-- 表单控件 -->
  <label for="username">用户名:</label>
  <input type="text" id="username" name="username" ngModel>
  <label for="password">密码:</label>
  <input type="password" id="password" name="password" ngModel>
  <!-- 提交按钮 -->
  <button type="submit">提交</button>
</form>

html
<form (ngSubmit)="onSubmit()" #myForm="ngForm">
  <!-- 表单控件 -->
  <label for="emAIl">邮箱:</label>
  <input type="emAIl" id="emAIl" name="emAIl" ngModel required>
  <label for="message">消息:</label>
  <textarea id="message" name="message" ngModel></textarea>
  <!-- 提交按钮 -->
  <button type="submit" [disabled]="!myForm.valid">提交</button>
</form>

html
<form (ngSubmit)="onSubmit()" #myForm="ngForm">
  <!-- 表单控件 -->
  <label for="username">用户名:</label>
  <input type="text" id="username" name="username" ngModel required>
  <label for="password">密码:</label>
  <input type="password" id="password" name="password" ngModel required>
  <!-- 提交按钮 -->
  <button type="submit" [disabled]="!myForm.valid">提交</button>
</form>