刷新网页 表单把空数据提交了怎么修改，谢谢

刷新网页  表单把空数据提交了怎么修改，目的是不要显示用户名不能为空这些


    <form action="${pageContext.request.contextPath}/RegisterServlet" method="post">
    <h3 align="center">注册</h3>
    <table width=40% border="1" align="center">
        <tr>
            <td width="20%">用户名 </td>
            <td>
            <input type="text" name="username" value="${formbean.username}" style="width: 30%">${formbean.errors.username}
            </td>
            </tr>
        <tr>
            <td width="20%">密码</td>
            <td>
            <input type="password" name="password" value="${formbean.password}" style="width: 30%">${formbean.errors.password}
            </td>
        </tr>

[此贴子已经被作者于2018-5-31 23:23编辑过]