如何实现“弹出提示框”
各位高手,我是个菜鸟,下面的代码在没有正确输入是如何实现“弹出错误提示框”<form ACTION="<%=MM_editAction%>" METHOD="POST" name="form2" onSubmit="MM_validateForm('name','','R','email','','RisEmail','qq','','RisNum','pwd','','R');MM_validateForm('name','','R','email','','RisEmail','qq','','RisNum','msn','','NisEmail','pwd','','R');return document.MM_returnValue">
<table width="754" border="1" bgcolor="#CCFFFF">
<tr>
<th width="341" rowspan="9" scope="col">
<table align="center" bgcolor="#CCFFFF">
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">用户名</span></td>
<td> <input name="name" type="text" value="" size="32"></td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">密码</span></td>
<td>
<input name="pwd" type="password" value="" size="35">
</td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">电子邮件</span></td>
<td>
<input name="email" type="text" value="" size="32">
</td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">密码提示问题</span></td>
<td>
<input name="question" type="text" value="" size="32">
</td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">密码提示答案</span></td>
<td>
<input name="answer" type="text" value="" size="32">
</td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">QQ</span></td>
<td>
<input name="qq" type="text" value="" size="32">
</td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">MSN</span></td>
<td>
<input name="msn" type="text" value="" size="32">
</td>
</tr>
<tr valign="baseline">
<td align="right" nowrap class="style4"><span class="style5">个人主页</span></td>
<td>
<input name="url" type="text" value="" size="32">
</td>
</tr>
<tr valign="baseline">
<td nowrap align="right"><span class="style5"></span></td>
<td>
<div align="right" class="style5">
<input name="submit" type="submit" value="提交注册">
<input type="reset" name="Submit" value="重置">
</div></td>
</tr>
</table>
</th>
<th width="431" height="19" class="style4" scope="col"><div align="left" class="style31 style46 style58">必填项</div></th>
</tr>
<tr>
<th height="17" class="style4" scope="col"><div align="left" class="style58">
<div align="left" class="style31 style59">必填项</div>
</div></th>
</tr>
<tr>
<th height="17" class="style4" scope="col"><div align="left" class="style31 style46 style58">必填项“您的邮箱”</div></th>
</tr>
<tr>
<th height="17" class="style4" scope="col"><div align="left" class="style31 style46 style58">可选项:忘记密码时取回密码用,如:“我的名字”</div></th>
</tr>
<tr>
<th height="17" class="style4" scope="col"><div align="left" class="style58"><span class="style49"><span class="style31 style46 style58">可选项:</span>填上名字,如:“王杰”</span></div></th>
</tr>
<tr>
<th height="19" class="style4" scope="col"><div align="left" class="style31 style46 style58">必填项</div></th>
</tr>
<tr>
<th height="19" class="style4" scope="col"><div align="left" class="style58"><span class="style49"><span class="style31 style46 style58">可选项:</span>必需是MSN邮箱</span></div></th>
</tr>
<tr>
<th class="style4" scope="col"><div align="left" class="style58"><span class="style49"><span class="style31 style46 style58">可选项:</span>个人网页链接</span></div></th>
</tr>
<tr>
<th scope="col"> </th>
</tr>
</table>
<input type="hidden" name="MM_insert" value="form2">
</form>