使用jquery
1 引入jquery的js文件在页面
<script type="text/javascript" src="<%=request.getContextPath() %>/jxc/js/jquery-1.4.2.min.js"></script>
2 下拉select
<select name="st_tid" id="t_id" onchange="goodsajax(this.options[this.selectedIndex].value);">
<option value="">请选择</option>
<c:forEach var="obj" items="${tlst}">
<option value="${obj.t_id }">${obj.t_name }</option>
</c:forEach>
</select>
<select name="st_gid" id="st_gid">
<option value="">请选择</option>
</select>
3 写js
function goodsajax(tid){
if(tid==""){return ;}
$('#st_gid').load("<%=request.getContextPath()%>/goods.do?methods=gajax&t_id="+tid+"&mm="+new Date().getTime());
}
4 js 提交action
Map map = new HashMap();
if(request.getParameter("t_id") == null || request.getParameter("t_id").equals("")){
return null;
}
map.put("t_id", request.getParameter("t_id"));
GoodsDao gDao = new GoodsDao();
request.setAttribute("glst", gDao.quertList(map));
return new ActionForward("/jxc/goods_ajax.jsp");
5
<%@ page language="java" pageEncoding="utf-8"%>
<%@ taglib uri = "
http://java.sun.com/jsp/jstl/core" prefix="c"%>
<option value="">请选择</option>
<c:forEach items="${glst}" var="obj">
<option value="${obj.g_id}">${obj.g_name}</option>
</c:forEach>