有三个表shop_anclass，shop_nclass，xhclass,后两个表行依据shop_anclass生成，现在通过，读出shop_anclass表，在中改变，而改变后两个选择框中类容，shop_nclass，xhclass不相关，可以实现选择第一个下拉框第二个下拉框中的选项变化，但是第三个下拉框不变化，不知道问题在那里，仔细看是对javascript语句不懂，贴出代码忘高人指导，谢谢
<!--#include file="conn.asp"-->
<html>
<head>
<title>西北工程机械网</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<link href="../css.css" rel="stylesheet" type="text/css">
<style>
td{font-size:9pt;line-height:120%;color:#353535}
body{font-size:9pt;line-height:120%}
a:link { color: #000000; text-decoration: none }
a:visited { color: #000000; text-decoration: none }
a:active { color: #000000; text-decoration: none }
a:hover { color: #336699; text-decoration: none; position: relative; right: 0px; top: 1px }
</style>
</head>
<%dim count
set rs=server.createobject("adodb.recordset")
rs.open "select * from shop_Nclass order by Nclassidorder ",conn,1,1%>
<script language = "JavaScript">
var onecount;
onecount=0;
subcat = new Array();
<%
count = 0
do while not rs.eof
%>
subcat[<%=count%>] = new Array("<%= trim(rs("Nclass"))%>","<%= rs("anclassid")%>","<%= rs("Nclassid")%>");
<%
count = count + 1
rs.movenext
loop
rs.close
%>
onecount=<%=count%>;
function changelocation(locationid)
{
document.myform.Nclassid.length = 0;
var locationid=locationid;
var i;
for (i=0;i < onecount; i++)
{
if (subcat[i][1] == locationid)
{ //这句不是很理解
document.myform.Nclassid.options[document.myform.Nclassid.length] = new Option(subcat[i][0], subcat[i][2]);
document.myform.xhclassid.options[document.myform.xhclassid.length] = new Option(subcat[i][0], subcat[i][2]);
}
}
}
</script>
<body>
<table width="205" border="0" align="center" cellpadding="1" cellspacing="1" bgcolor="#CCCCCC">
<tr>
<form name="myform" method="post" action="saveaddbook.asp" >
<td height="126" bgcolor="#FFFFFF">
<table width="201" border="0" align="center" cellpadding="2" cellspacing="0">
<tr>
<td>交易类型：</td>
<td width="62%"> <select name="fudongjia" size=1 class="wenbenkuang">
<%set rs_s=server.createobject("adodb.recordset")
rs_s.open "select * from shop_fudong order by id ",conn,1,1
if rs_s.recordcount=0 then
response.write "请先添加交易类型！"
else
while not rs_s.eof
%>
<option value=<%=rs_s("id")%> selected ><%=rs_s("shuoming")%></option>
<%
rs_s.movenext
wend
end if%>
</select></td>
</tr>
<tr>
<td width="38%">设备类型：</td>
<td> <%
rs.open "select * from shop_anclass order by anclassidorder",conn,1,1
if rs.eof and rs.bof then
response.write "请先添加栏目。"
response.end
else
%> <select name="anclassid" size="1" id="anclassid" onChange="changelocation(document.myform.anclassid.options[document.myform.anclassid.selectedIndex].value)" class="wenbenkuang">
<option selected value="<%=rs("anclassid")%>"><%=trim(rs("anclass"))%></option>
<% dim selclass
selclass=rs("anclassid")
rs.movenext
do while not rs.eof
%>
<option value="<%=rs("anclassid")%>"><%=trim(rs("anclass"))%></option>
<%
rs.movenext
loop
end if
rs.close
%>
</select>
</td>
</tr>
<tr>
<td width="38%">生产厂商：</td>
<td><select name="Nclassid" class="wenbenkuang">
<%rs.open "select * from shop_Nclass where anclassid="&selclass ,conn,1,1
if not(rs.eof and rs.bof) then
%>
<option selected value="<%=rs("NclassID")%>"><%=rs("Nclass")%></option>
<% rs.movenext
do while not rs.eof%>
<option value="<%=rs("NclassID")%>"><%=rs("Nclass")%></option>
<% rs.movenext
loop
end if
rs.close
'set rs = nothing
%>
</select></td>
</tr>
<tr>
<td width="38%">设备型号：</td>
<%response.Write("selclass")%>
<td> <select name="xhclassid" class="wenbenkuang" id="xhcalss">
<% rs.open "select * from xhclass where anclassid="&selclass ,conn,1,1
if not(rs.eof and rs.bof) then
%>
<option selected value="<%=rs("xhclassid")%>"><%=rs("xhclass")%></option>
<% rs.movenext
do while not rs.eof%>
<option value="<%=rs("xhclassid")%>"><%=rs("xhclass")%></option>
<% rs.movenext
loop
end if
rs.close
set rs = nothing
%>
</select></td>
</tr>
<tr>
<td width="38%">价格范围：</td>
<td><select class=a name=select>
<option value="kong" selected>请选择价格范围</option>
<option>1万以下</option>
<option>10-20万</option>
<option>20万以上</option>
</select></td>
</tr>
<tr align="center">
<td height="18" colspan="2"> <INPUT class=button name=submit22232 type=submit value=点击查看结果>
</td>
</tr>
</table></td>
</form>
</tr>
</table>
<br>
</body>
</html>
