这两天在做一个项目,分类想用slect联动,但遇到“不能得到描述信息:Not Found”问题,求助...
js代码如下:var req;
window.onload=function()
{//页面加载时的函数
}
function Change_Select(){ //当第一个下拉框的选项发生改变时调用该函数
var col = document.getElementById('column1').value;
var url = "select?id="+ col;
if(window.XMLHttpRequest){
req = new XMLHttpRequest();
}else if(window.ActiveXObject){
req = new ActiveXObject("Microsoft.XMLHTTP");
}
if(req){
req.open("GET",url,true);
//指定回调函数为callback
req.onreadystatechange = callback;
req.send(null);
}
}
//回调函数
function callback(){
if(req.readyState ==4){
if(req.status ==200){
parseMessage();//解析XML文档
}else{
alert("不能得到描述信息:" + req.statusText);
}
}
}
//解析返回xml的方法
function parseMessage(){
var xmlDoc = req.responseXML.documentElement;//获得返回的XML文档
var xSel = xmlDoc.getElementsByTagName('select');
//获得XML文档中的所有<select>标记
var select_root = document.getElementById('column2');
//获得网页中的第二个下拉框
select_root.options.length=0;
//每次获得新的数据的时候先把每二个下拉框架的长度清0
for(var i=0;i<xSel.length;i++){
var xValue = xSel[i].childNodes[0].firstChild.nodeValue;
//获得每个<select>标记中的第一个标记的值,也就是<value>标记的值
var xText = xSel[i].childNodes[1].firstChild.nodeValue;
//获得每个<select>标记中的第二个标记的值,也就是<text>标记的值
var option = new Option(xText, xValue);
//根据每组value和text标记的值创建一个option对象
//var option2=String.formCharCode(option);
try{
select_root.add(option);//将option对象添加到第二个下拉框中
}catch(e){
}
}
}
jsp代码:<select name="column1" id="column1" onchange=" Change_Select()">
<option value="0" >请选择</option>
<%
List<column1> columns=column1.findAll();
for(int i=0;i<columns.size();i++){
column1 col=columns.get(i);
%>
<option value="<%=col.getCid1()%>" ><%=col.getCname1() %></option>
<% }
%>
</select> <select name="column2" id="column2" >
<option value="0" >请选择</option>
</select></td>
servlet代码public class SelectServlet extends HttpServlet
{ private static final long serialVersionUID = 1L; public SelectServlet()
{
super();
} public void destroy()
{
super.destroy();
} public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
// response.setCharacterEncoding("GBK");
response.setContentType("text/xml");
response.setHeader("Cache-Control", "no-cache");
request.setCharacterEncoding("GBK");
response.setCharacterEncoding("UTF-8");
int targetId = Integer.parseInt(request.getParameter("id"));
// targetId=new String(targetId.getBytes("ISO-8859-1"),"gbk");//将已经乱码的参数转码为中文
System.out.println(targetId);
// 获得请求中参数为id的值
String xml_start = "<selects>";
String xml_end = "</selects>";
String xml = "";
List<column2> columns=column2.findAll(targetId);
column2 col;
for(int i=0;i<columns.size();i++){
col=columns.get(i);
xml += "<select><value>" + col.getCid2()+ "</value><text>" + col.getCname2()+ "</text></select>"; }
String last_xml = xml_start + xml + xml_end;
response.getWriter().write(last_xml); } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
this.doGet(request, response);
}xml配置:
<servlet>
<servlet-name>SelectServlet</servlet-name>
<servlet-class>com.zsq.javabean.SelectServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>SelectServlet</servlet-name>
<url-pattern>/servlet/SelectServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>addNews.jsp</welcome-file>每次运行都是提醒“不能得到描述信息:Not Found”,求助各位网友!
js代码如下:var req;
window.onload=function()
{//页面加载时的函数
}
function Change_Select(){ //当第一个下拉框的选项发生改变时调用该函数
var col = document.getElementById('column1').value;
var url = "select?id="+ col;
if(window.XMLHttpRequest){
req = new XMLHttpRequest();
}else if(window.ActiveXObject){
req = new ActiveXObject("Microsoft.XMLHTTP");
}
if(req){
req.open("GET",url,true);
//指定回调函数为callback
req.onreadystatechange = callback;
req.send(null);
}
}
//回调函数
function callback(){
if(req.readyState ==4){
if(req.status ==200){
parseMessage();//解析XML文档
}else{
alert("不能得到描述信息:" + req.statusText);
}
}
}
//解析返回xml的方法
function parseMessage(){
var xmlDoc = req.responseXML.documentElement;//获得返回的XML文档
var xSel = xmlDoc.getElementsByTagName('select');
//获得XML文档中的所有<select>标记
var select_root = document.getElementById('column2');
//获得网页中的第二个下拉框
select_root.options.length=0;
//每次获得新的数据的时候先把每二个下拉框架的长度清0
for(var i=0;i<xSel.length;i++){
var xValue = xSel[i].childNodes[0].firstChild.nodeValue;
//获得每个<select>标记中的第一个标记的值,也就是<value>标记的值
var xText = xSel[i].childNodes[1].firstChild.nodeValue;
//获得每个<select>标记中的第二个标记的值,也就是<text>标记的值
var option = new Option(xText, xValue);
//根据每组value和text标记的值创建一个option对象
//var option2=String.formCharCode(option);
try{
select_root.add(option);//将option对象添加到第二个下拉框中
}catch(e){
}
}
}
jsp代码:<select name="column1" id="column1" onchange=" Change_Select()">
<option value="0" >请选择</option>
<%
List<column1> columns=column1.findAll();
for(int i=0;i<columns.size();i++){
column1 col=columns.get(i);
%>
<option value="<%=col.getCid1()%>" ><%=col.getCname1() %></option>
<% }
%>
</select> <select name="column2" id="column2" >
<option value="0" >请选择</option>
</select></td>
servlet代码public class SelectServlet extends HttpServlet
{ private static final long serialVersionUID = 1L; public SelectServlet()
{
super();
} public void destroy()
{
super.destroy();
} public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
// response.setCharacterEncoding("GBK");
response.setContentType("text/xml");
response.setHeader("Cache-Control", "no-cache");
request.setCharacterEncoding("GBK");
response.setCharacterEncoding("UTF-8");
int targetId = Integer.parseInt(request.getParameter("id"));
// targetId=new String(targetId.getBytes("ISO-8859-1"),"gbk");//将已经乱码的参数转码为中文
System.out.println(targetId);
// 获得请求中参数为id的值
String xml_start = "<selects>";
String xml_end = "</selects>";
String xml = "";
List<column2> columns=column2.findAll(targetId);
column2 col;
for(int i=0;i<columns.size();i++){
col=columns.get(i);
xml += "<select><value>" + col.getCid2()+ "</value><text>" + col.getCname2()+ "</text></select>"; }
String last_xml = xml_start + xml + xml_end;
response.getWriter().write(last_xml); } public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
this.doGet(request, response);
}xml配置:
<servlet>
<servlet-name>SelectServlet</servlet-name>
<servlet-class>com.zsq.javabean.SelectServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>SelectServlet</servlet-name>
<url-pattern>/servlet/SelectServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>addNews.jsp</welcome-file>每次运行都是提醒“不能得到描述信息:Not Found”,求助各位网友!
比如说提示的这个:不能得到描述信息:Not Found;
你就看你的这个代码:
if(req.status ==200){
parseMessage();//解析XML文档
}else{
alert("不能得到描述信息:" + req.statusText);
}
alert一下req.status是否等于200。如果不是200,你提问题就可以只用一句话“为什么不是200?”。什么东西都一股脑贴上来,谁看了不晕。