ajax+Servlet 页面没有返回的结果
热情的菠菜 2012-05-08 03:25:38 servlet 代码:
package com.qt.inquiry;
import com.ht.javabean.DB;
import java.io.*;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;
public class BusServlet extends HttpServlet
{
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException
{
resp.setContentType("text/html;charset=utf-8");
resp.setHeader("Cache-Control", "no-cache");
resp.setHeader("Pragma","no-cache");
resp.setDateHeader("Expires",0);
String busname=req.getParameter("busname");
DB db=new DB();
try
{
String sql="select * from BusLine where BL_Num='"+busname+"'";
ResultSet rs=db.executeQuery(sql);
String info_go=rs.getString("BL_S_Go");
String info_return=rs.getString("BL_S_Return");
StringBuffer buffer=new StringBuffer();
buffer.append("<p>");
buffer.append("<lable>");
buffer.append("上行路线:");
buffer.append("</lable>");
buffer.append(info_go);
buffer.append("</p>");
buffer.append("<p>");
buffer.append("<lable>");
buffer.append("下行路线:");
buffer.append("</lable>");
buffer.append(info_return);
buffer.append("</p>");
PrintWriter out = resp.getWriter();
out.write(buffer.toString());
//out.write(busname);
out.close();
}
catch (SQLException e)
{
e.printStackTrace();
}
}
}
web.xml文件:
<servlet>
<servlet-name>BusServlet</servlet-name>
<servlet-class>com.qt.inquiry.BusServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>BusServlet</servlet-name>
<url-pattern>/BusServlet</url-pattern>
</servlet-mapping>
index.jsp页面
<form name="BusServlet" method="get"><table>
<tr><td>车次名:</td><td><input type="text" name="busname"/></td></tr>
<tr><td align="center"><input type="button" value="查询" onClick="createXMLHttpRequest('/BusSystem/BusServlet?busname='+document.BusServlet.busname.value);"/></td><td align="center"><input type="reset" value="更改"/></td></tr>
</table></form>
<script type="text/javascript">
function getResult()
{
if(xmlHttp.readyState==4)
{
if(xmlHttp.status==200)
{
document.getElementById("result").innerHTML=xmlHttp.responseText;
//document.getElementById("result").style.display="block";
}
else
{
alert('您请求的页面有错误'+xmlHttp.status);
}
}
}
function createXMLHttpRequest(url)
{
var URL=url;
//Mozilla 浏览器(将XMLHttpRequest对象作为本地浏览器对象来创建)
if(window.XMLHttpRequest)
{ //Mozilla 浏览器
xmlHttp = new XMLHttpRequest();
}
else if(window.ActiveXObject)
{ //IE浏览器
//IE浏览器(将XMLHttpRequest对象作为ActiveX对象来创建)
try
{
xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(e)
{
try
{
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
catch(e)
{}
}
}
if(!xmlHttp)
{
alert("不能创建XMLHttpRequest对象");
return false;
}
xmlHttp.open("GET",URL,true);
xmlHttp.onreadystatechange=getResult;
xmlHttp.send(null);
}
</script>