<fieldset>
<legend>用户登录</legend>
<div class="box_a">
<label for="uName">用户名:</label><input class="text_a" id="uName" type="text">
</div>
<div class="box_a">
<label for="uPassword">密 码:</label><input class="text_a" id="uPassword" type="text">
</div>
<div class="box_a">
<input id="uTrue" type="checkbox"><label for="uTrue">记住我</label>
</div>
</fieldset>
fieldset标签搭配legend轻松实现GroupBox。