数据库表设计

字段ClassID,ClassName,ClassType,ParentClassID

• ClassID类别ID
• ClassName类别名称
• ClassType=1 顶级分类
• ClassType=2一级分类
• ClassType=3二级分类

ParentClassID父类ClassID，顶类的父类默认为0

脚本代码

<%
sql = "select * from Bs_ProductClass where ClassType=2 order by ClassID asc"
set rs = conn.execute(sql)
%>
<script language = "JavaScript">
　var onecount;
　onecount=0;
　subcat = new Array();
<%
count1 = 0
do while not rs.eof
%>
subcat[<%=count1%>] = new Array("<%= trim(rs("ClassName"))%>","<%= trim(rs("ParentClassID"))%>","<%= trim(rs("ClassID"))%>");
<%
count1 = count1 + 1
rs.movenext
loop
rs.close
set rs=nothing
%>
onecount=<%=count1%>;

function changelocation(ClassID1)
{
　　document.myform.BigClassID.length = 0;
　　var ClassID1=ClassID1;
　　var i;
　　var op1 = document.createElement("OPTION");
　　document.myform.BigClassID.options[0] = new Option('==所属大类名称==',' ');
　　for (i=0;i < onecount; i++)
　　{
　　　　if (subcat[i][1] == ClassID1)
　　　　{
　　　　　　op1= new Option(subcat[i][0], subcat[i][2]);
　　　　　　document.myform.BigClassID.options.add(op1);
　　　　}
　　}

}
</script>

<%sql2 = "select * from Bs_ProductClass where ClassType=3 order by ClassID asc"
set rs2 = conn.execute(sql2)
%>
<script language = "JavaScript">
var onecount2;
onecount2=0;
subcat2 = new Array();
<%
count2 = 0
do while not rs2.eof
%>
subcat2[<%=count2%>] = new Array("<%= trim(rs2("ClassName"))%>","<%= trim(rs2("ParentClassID"))%>","<%= trim(rs2("ClassID"))%>");
<%
count2 = count2 + 1
rs2.movenext
loop
rs2.close
set rs2=nothing
%>
onecount2=<%=count2%>;

function changelocation2(ClassID2)
{
　　document.myform.SmallClassID.length = 0;

　　var ClassID2=ClassID2;
　　var j;
　　var op2 = document.createElement("OPTION");
　　document.myform.SmallClassID.options[0] = new Option('==所属小类名称==',' ');
　　for (j=0;j < onecount2; j++)
　　{
　　　　if (subcat2[j][1] == ClassID2)
　　　　{
　　　　　　op2 = new Option(subcat2[j][0], subcat2[j][2]);
　　　　　　document.myform.SmallClassID.options.add(op2);
　　　　}
　　}

}
</script>

调用代码

<form name='myform'>

<select name="TopClassID" id="TopClassID" onChange="changelocation(document.myform.TopClassID.options.value)" size="1">
<option selected value="">请选择所属顶类</option>
<%

sql1 = "select * from Bs_ProductClass where ClassType=1 order by ClassID asc"
set rs1 = conn.Execute (sql1)
do while not rs1.eof
%>
<option value="<%=trim(rs1("ClassID"))%>"><%=trim(rs1("ClassName"))%></option>

<%
rs1.movenext
loop
rs1.close
set rs1 = nothing
conn.Close
set conn = nothing
%>
</select>
大类
<select name="BigClassID" id="BigClassID" onChange="changelocation2(document.myform.BigClassID.options[this.options.selectedIndex].value)">
<option selected value="">==所有大类==</option>
</select>
小类
<select name="SmallClassID" id="SmallClassID" size="1">
<option selected value="">==所有小类==</option>
</select>

</form>