AngularLearn/src/app/app.component.html

<form #form="ngForm">
  <div>帳號:<input type="text" name="id" #id="ngModel" ngModel /></div>
  <div>
    密碼:<input type="password" name="password" #password="ngModel" ngModel />
  </div>
  <div>
    <button type="reset">重設</button>
    <button type="submit">登入</button>
  </div>
</form>

<br />
<h4>帳號狀態</h4>
<pre>是否曾經修改過:{{id.dirty |json}}</pre>
<pre>是否從未修改過:{{id.pristine |json}}</pre>

<br />
<h4>表單狀態</h4>
<pre>是否曾經修改過:{{form.dirty |json}}</pre>
<pre>是否從未修改過:{{form.pristine |json}}</pre>