#### 1.帶驗證，帶歷史記錄的表單；
~~~
<form action="#" method="post">
<input type="text" name="Name" value="姓 名"
onfocus="this.value = '';" onblur="if (this.value == '') {this.value = '姓 名';}">
<input type="email" name="Email" value="郵 箱" onfocus="this.value = '';" onblur="if (this.value == '') {this.value = '郵 箱';}" required="">
<input type="text" name="Mobile number" value="電話號碼" onfocus="this.value = '';" onblur="if (this.value == '') {this.value = '電話號碼';}" required="">
<textarea name="Message..." onfocus="this.value = '';" onblur="if (this.value == '') {this.value = '內 容...';}" required>內 容...</textarea>
<input type="submit" value="提 交">
</form>
~~~
說明：
1.有name屬性才能被服務器記錄你所輸入的記錄
2.onfocus：當元素獲得焦點是觸發的事件
3.onblur：當元素失去焦點時觸發的事件
4.required：驗證輸入的信息是否正確
