请教——关于表单镶套的问题
有如图示一个产品修改查询页面：页面代码：
程序代码：<!DOCTYPE html PUBLIC "-//WAPFORUM//DTD XHTML Mobile 1.0//EN" "http://www.>
<%@Language="VBScript" CodePage="65001"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>产品添加</title>
</head>
<%
dim conn
dim connstr
Connstr="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & Server.MapPath("dbdate/zswap.mdb")
Set conn = Server.CreateObject("ADODB.Connection")
Conn.Open Connstr
%>
<body>
<form id="search" name="search" method="post" action="ts1.asp" target="_parent">
<table width="600" border="0" cellspacing="0" cellpadding="0">
<tr>
<td width="50"><div align="center">序号</div></td>
<td width="250"><div align="center">产品编码</div></td>
<td><div align="center">产品类名</div></td>
<td width="50"><div align="center">查询</div></td>
</tr>
<tr>
<td> </td>
<td>
<div align="center">
<input name="searchtxt" type="text" id="searchtxt" size="30" />
</div></td>
<td><div align="center">
<input type="submit" name="searchgo" id="searchgo" value="搜索" />
</div></td>
<td> </td>
</tr>
<%
set rs=server.createobject("adodb.recordset")
if request("searchtxt")<>"" then
sql="select * from pro where cpid = '"&request("searchtxt")&"' order by id desc"
else
sql="select top 5 * from pro order by id desc"
end if
rs.open sql,conn,1,1
if rs.eof and rs.bof then
response.write " <script language=""javascript"">alert(""请核对产品编码！"")</script>"
end if
%>
<%
do while not rs.eof
%>
<form id="chaxun" name="chaxun" method="post" action="ts1.asp" target="_parent">
<tr>
<td><div align="center"><%=rs("id")%></div></td>
<td><div align="center"><%=rs("cpid")%></div></td>
<td><div align="center"><%=rs("cpname")%></div></td>
<td><div align="center">
<input type="submit" name="chaxun" id="chaxun" value="查询" />
</div></td>
</tr>
<%
set rs2=server.createobject("adodb.recordset")
sql2="select * from pro where id= "&rs("id")&" "
rs2.open sql2,conn,1,1
%>
</form>
<%
rs.movenext
loop
rs.close
%>
</table>
</form>
<form name="form1" method="post" action="ts2.asp" target="_parent">
<table width="600" border="0" cellspacing="0" cellpadding="0">
<tr>
<td width="90"><div align="right">产品编号： </div></td>
<td colspan="2"><input name="cpid" type="text" id="cpid" value="<%=rs2("cpid")%>"></td>
<td width="50%"><font color="#FF0000"> * </font><font color="#999999">如：PACD1020 </font></td>
</tr>
<tr>
<td><div align="right">产品名称： </div></td>
<td colspan="2"><input name="cpname" type="text" id="cpname" value="<%=rs2("cpname")%>"></td>
<td><font color="#FF0000">* </font><font color="#999999">如：亚克力珠</font></td>
</tr>
<tr>
<td><div align="right">产品大类： </div></td>
<td colspan="2"><input name="bigclass" type="text" id="bigclass" value="<%=rs2("bigclass")%>"></td>
<td><font color="#FF0000">* </font><font color="#999999">两类：1，亚克力sb1s；2，LED灯sb2s</font></td>
</tr>
<tr>
<td><div align="right">产品小类： </div></td>
<td colspan="2"><input name="smallclass" type="text" id="smallclass" value="<%=rs2("smallclass")%>"></td>
<td><font color="#FF0000">*</font><font color="#999999"> 如：亚克力珠，s11s</font></td>
</tr>
<tr>
<td><div align="right">图片地址： </div></td>
<td colspan="2"><input name="pic" type="text" id="pic" value="<%=rs2("pic")%>"></td>
<td><font color="#FF0000">*</font><font color="#999999"> 如：img/pccd0120.jpg</font></td>
</tr>
<tr>
<td><div align="right">产品规格： </div></td>
<td colspan="2"><input name="size" type="text" id="size" value="<%=rs2("size")%>"></td>
<td><font color="#999999">如：20*25*10 单位：mm</font></td>
</tr>
<tr>
<td><div align="right">详细资料：</div></td>
<td height="50" colspan="3"><textarea name="note" cols="50" rows="5" id="note"><%=rs2("note")%></textarea>
<font color="#FF0000">*</font></td>
</tr>
<tr>
<td><div align="right">验证码：</div></td>
<td width="131">
<input name="CheckCode" size="6" maxlength="4" style="border-style:solid;border-width:1;padding-left:4;padding-right:4;padding-top:1;padding-bottom:1" onmouseover="this.style.background='#E1F4EE';" onmouseout="this.style.background='#FFFFFF'" onfocus="this.select(); " />
<img src="checkcode.asp" alt="" /><font color="#FF0000">*</font></td>
<td width="65"><input type="submit" name="up" id="up" value="提交" /></td>
<td> </td>
</tr>
</table>
</form>
</body>
</html>
目前的问题是，当没有查询关键词时，不能点击列出的查询按钮查询该ID产品，当查询无结果时，RS2（“ID”）无返回而报错请教解决办法
