a标记提交表单
表单 设施id=“loginform”
<form id="loginform" action="/login" method="post">
<a onclick="document:loginform.submit()" >登 录</a>
<form id="loginform" action="/login" method="post">
<input id="prependedInput" type="text" name="username" placeholder="邮箱/用户名/手机号" class="span2 input-xfat">
<input id="prependedInput" name="password" type="password" placeholder="请输入密码" class="span2 input-xfat">
<a onclick="document:loginform.submit()" >登 录</a>
</form>