用JSP+JavaScript打造二级级联下拉菜单-----方法二

<%@ page contentType=text/html; charset=GB2312 language=java errorPage=../error.jsp %>
<%@ include file=../conn.jsp%>
<%@ include file=../ds.jsp%>
<%@ taglib uri=http://java.sun.com/jsp/jstl/sql divfix=sql %>
<%request.setCharacterEncoding(gb2312); %>
<HTML><HEAD>
<META. http-equiv=Content-Type content=text/html; charset=gb2312>

<TITLE>级联菜单</TITLE>
<LINK rel=stylesheet type=text/css href=style.css>
</HEAD>
<!--从数据库中得到二级栏目信息-->
<%String sql=select * from Nclass order by NclassId asc;
ResultSet rs=stmt.executeQuery(sql);
%>
<!--将二级栏目信息保存到数组subcat中-->
<script. type=text/javascript>
var onecount;
necount=0;
subcat = new Array();
        <%
        int count = 0;
        while(rs.next()){
        %>
subcat[<%=count%>] = new Array(<%=rs.getString(NclassName)%>,
<%=rs.getString(NclassId)%>,<%=rs.getString(parentId)%>);
        <%
        count++;
        }
        rs.close();
        %>
necount=<%=count%>;
<!--决定select显示的函数-->
function changelocation(locationid)
    {
    document.myform.NclassId.length = 0;

    var locationid=locationid;
    var i;
    for (i=0;i < onecount; i++)
        {
            if (subcat[i][2] == locationid)
            {
                document.myform.NclassId.options[document.myform.NclassId.length] = new
Option(subcat[i][0], subcat[i][1]);
            }       
        }
       
    }   
</script>

<FORM. method=POST name=myform. action=adminsave.jsp?action=add>
  <TABLE>
  
    <TR>
      <TD>一级分类</TD>
      <TD> 
        <SELECT name=classId nChange=changelocation(document.myform.classId.options
[document.myform.classId.selectedIndex].value) size=1>
          <OPTION selected value>==请选一级分类==</OPTION>
        <sql:query var=query dataSource=___FCKpd___0gt;
          SELECT * FROM class
       </sql:query>
<c:forEach var=row items=___FCKpd___0gt;
<option value=___FCKpd___0gt;___FCKpd___0lt;/option>
</c:forEach>
</select>
      </TD>
      <TD>选择二级分类</TD>
      <TD>
        <SELECT name=NclassId>
          <OPTION selected value>==请选二级分类==</OPTION>
        </SELECT>
      </TD>
    </TR>
</TABLE>
 
</FORM>
</BODY>
</HTML>