<%@ page language="java" pageEncoding="UTF-8"%>
<%@ page import="java.util.*" %>
<%@ page import="edu.syict.www.dao.*" %>
<%@ page import="edu.syict.www.POJO.*" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'menu.jsp' starting page</title>
</head>
<body>
<%
Country c=null ;
DBOperator dbo=new DBOperator() ;
List listname=dbo.query("SELECT DISTINCT co.name FROM Country AS co") ;
List listcity=dbo.query("SELECT DISTINCT co.city FROM Country AS co") ;
%>
<center>
<script type="text/javascript">
var XMLHttpReq;
var currentSort;
//创建XMLHttpRequest对象
function createXMLHttpRequest() {
if(window.XMLHttpRequest) { //Mozilla 浏览器
XMLHttpReq = new XMLHttpRequest();
}
else if (window.ActiveXObject) { // IE浏览器
try {
XMLHttpReq = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
try {
XMLHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {}
}
}
}
//发送请求函数
function sendRequest(url) {
createXMLHttpRequest();
XMLHttpReq.open("GET", url, true);
XMLHttpReq.onreadystatechange = processResponse;//指定响应函数
XMLHttpReq.send(null); // 发送请求
}
// 处理返回信息函数
function processResponse() {
if (XMLHttpReq.readyState == 4) { // 判断对象状态
if (XMLHttpReq.status == 200) { // 信息已经成功返回,开始处理信息XMLHttpReq.status == 200
updateMenu();
} else { //页面不正常
alert("您所请求的页面有异常。");
}
}
}
//更新菜单函数
function updateMenu() {
var res=XMLHttpReq.responseXML.getElementsByTagName("res") ;
//alert("res===="+res[0].firstChild.nodeValue);
/**下面是用innerHTML输出控件内容的一般用法**/
//var subMenu = "";
//for(var i = 0; i < res.length; i++) {
// subMenu = subMenu + " " + res[i].firstChild.data + "";
//}
//currentSort.innerHTML = subMenu;
var list = document.all.list;
list.options.length=0;
list.add(new Option("---请选择---",""));
for(var i=0;i<res.length;i++){
list.add(new Option(res[i].firstChild.nodeValue,res[i].firstChild.nodeValue));
}
}
// 创建级联菜单函数
function showSubMenu(obj) {
//currentSort =document.getElementById(obj);
//currentSort.parentNode.style.display = "";
sendRequest("menujsp.jsp?sort=" + obj);
/**下面这一句的作用是:每次选择后回到第一个选项**/
//document.all.mli.options[0].selected=true;
}
</script>
<select name="mli" onchange="showSubMenu(this.options[this.options.selectedIndex].value)" style="width:150px;">
<option value="">---bbb---</option>
<%
for(int i=0;i<listname.size();i++){
//c=(Country)listname.get(i) ;
out.println("<option value='"+listname.get(i)+"'>"+listname.get(i)+"</option>") ;
}
%>
</select>
<select name="list" style="width:100px;">
<option value="">---aaa---</option>
<%
for(int i=0;i<listcity.size();i++){
out.println("<option value='"+listcity.get(i)+"'>"+listcity.get(i)+"</options>") ;
}
%>
</select>
<br>
</center>
</body>
</html> |