不多说了，看代码吧！哈哈！
<1>index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page contentType="text/html;charset=UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
String searchType = request.getParameter("tab");
int i = 0;
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<style type="text/css">
<!--
.STYLE1 {color: #FFFFFF}
body {
background-color: white;
}
#Layer1 {
position:absolute;
400px;
height:146px;
z-index:1;
left: 424px;
top: 242px;
}
-->
</style>
<meta http-equiv="Content-Type" content="text/html; charset=GBK">
</head>
<%
if (null == searchType)
searchType = "all";
%>
<script type="text/javascript">
var xmlHttpRequest;
function createXmlHttpRequest()
{
if(window.ActiveXObject)
{
try
{
xmlHttpRequest = new ActiveXObject("Microsoft.XMLHTTP");
}
catch(e)
{
xmlHttpRequest = new ActiveXObject("Msxml2.XMLHTTP");
}
return xmlHttpRequest;
}
else if(window.XMLHttpRequest)
{
return new XMLHttpRequest();
}
}
function auto()
{
var query = document.getElementById("query");
var auto = document.getElementById("auto");
var tags = document.getElementById("tags");
if(event.keyCode == 40)
{
if(query.value != "" && auto.style.visibility != "hidden")
{
tags.focus();
tags.selectedIndex = 0;
query.value = tags.options[0].text;
return;
}
}
xmlHttpRequest = createXmlHttpRequest();
xmlHttpRequest.onreadystatechange = backFct;
var url = "AjaxindexAction.action?tag=" + query.value;
xmlHttpRequest.open("post",url,true);
xmlHttpRequest.send(null);
}
function backFct()
{
if(xmlHttpRequest.readyState == 4 && xmlHttpRequest.status == 200)
{
var rs = xmlHttpRequest.responseText;
if(rs != "")
{
var tagsRs = rs.split(",");
var auto = document.getElementById("auto");
var tags = document.getElementById("tags");
var query = document.getElementById("query");
tags.length = 0;
tags.size = tagsRs.length;
for(var i=0;i<tagsRs.length;i++)
{
var option = document.createElement("option");
option.setAttribute("text", tagsRs[i]);
tags.options[i] = option;
}
auto.style.width = query.style.width;
tags.style.width = query.style.width;
auto.style.left = query.offsetLeft - 1;
auto.style.top = query.offsetTop + query.offsetHeight + 1;
auto.style.visibility = "visible";
}
else
{
document.getElementById("auto").style.visibility = "hidden";
}
}
}
function text()
{
var query = document.getElementById("query");
var auto = document.getElementById("auto");
var tags = document.getElementById("tags");
if(event.keyCode == 40 || event.keyCode == 38)
{
if(query.value != "" && auto.style.visibility != "hidden")
{
query.value = tags.options[tags.selectedIndex].text;
}
}
else if(event.keyCode == 13)
{
auto.style.visibility = "hidden";
query.focus();
}
}
</script>
<body>
<div align="center">
<table width="1240" border="0">
<tr>
<td width="643"><div align="left">
<%if(session.getAttribute("user")!=null){
out.println( "欢迎"+ session.getAttribute("user")+" 您已经登录");
} %>
</div></td>
<td width="581"><div align="right"><a href="login.jsp" >登录 </a>
| <a href="regin.jsp" >注册 </a>
| <a href="invalidate.action" >注销</a>
| <a href="Upload.jsp" >上传 </a>
</div></td>
</tr>
</table>
<br>
<br>
<br>
<span class="STYLE1"></span> <br>
</div>
<div align="center">
<form id="searchForm" name="searchForm" action="search.action"
method="post">
<div align="right">
<p> </p>
<table width="471" border="0" align="center">
<tr>
<td width="461" height="42"><div align="center"></div></td>
</tr>
<tr>
<td height="65"><table border="0" align="center" width="452">
<tr size="80">
<td width="61" height="21" align="center"><%
if (searchType.equals("all"))
out.println("<strong>全部</strong>");
else
out.println("<a href='index.jsp?tab=all&i=0'>全部</a>");
%> </td>
<td width="61" align="center"><%
if (searchType.equals("doc"))
out.println("<strong>文档</strong>");
else
out.println("<a href='index.jsp?tab=doc&i=0'>文档</a>");
%> </td>
<td width="61" align="center"><%
if (searchType.equals("mov"))
out.println("<strong>视频</strong>");
else
out.println("<a href='index.jsp?tab=mov&i=0'>视频</a>");
%> </td>
<td width="61" align="center"><%
if (searchType.equals("music"))
out.println("<strong>音乐</strong>");
else
out.println("<a href='index.jsp?tab=music&i=0'>音乐</a>");
%> </td>
<td width="56" align="center"><%
if (searchType.equals("other"))
out.println("<strong>其他</strong>");
else
out.println("<a href='index.jsp?tab=other&i=0'>其他</a>");
%> </td>
<td width="126"></td>
</tr>
<tr>
<td colspan="5">
<input type="text" name="keywords" id="query" onKeyUp="auto();" style=" 400px; height: 30px; font-size: 18px; background-color:white"/>
</td>
<td><input type="hidden" name="searchType" value="<%=searchType%>" />
<input type="hidden" name="i" value="<%=i%>" />
<input name="submit" type="submit" style="height:32px; " value="搜索一下" />
</td>
</tr>
</table></td>
</tr>
</table>
<div id="Layer1"></div>
<p> </p>
<p> </p>
</div>
</form>
</div>
<div id="auto" style="border-style: solid; border- 1px; visibility: hidden; position: absolute;margin-left:429px;margin-top:230px">
<select id="tags" onkeyup="text();" size="0" style=" margin:-2px;">
</select>
</div>
</body>
</html>
<2>AjaxindexAction
package com.dreamers.login;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.interceptor.ServletRequestAware;
import org.apache.struts2.interceptor.ServletResponseAware;
import org.dom4j.DocumentException;
import com.dreamers.xml.XmlReader;
import com.opensymphony.xwork2.ActionSupport;
public class AjaxindexAction extends ActionSupport implements ServletRequestAware ,ServletResponseAware{
private static final long serialVersionUID = 1L;
private HttpServletRequest request;
private HttpServletResponse response;
private List<String> db = new ArrayList<String>();
public void setServletRequest(HttpServletRequest request) {
this.request =request;
}
public void setServletResponse(HttpServletResponse response) {
this.response = response;
}
public void init() throws DocumentException
{
/*
db.add("Sean");
db.add("Sean's Space");
db.add("Sean's Computer");
db.add("Sean's Blog");
db.add("Sean Ajax");
db.add("Sean javaer");
db.add("John Web");
db.add("John.com");
db.add(".net");
db.add("java");
db.add("java framework");
db.add("java MyEclipse");
db.add("C++");
*/
XmlReader reader = new XmlReader();
db=reader.getTitle();
}
public String execute() throws Exception {
init() ;
System.out.println("doGet start");
String tag = request.getParameter("tag");
System.out.println(tag);
response.setContentType("text/html;charset=GBK");
if(tag != "")
{
String rs = "";
for(int i=0;i<this.db.size();i++)
{
if(this.db.get(i).startsWith(tag))
{
rs = rs + this.db.get(i) + ",";
}
}
if(rs != "")
{
rs = rs.substring(0, rs.length()-1);
}
System.out.println(rs);
PrintWriter pw = response.getWriter();
pw.write(rs);
pw.flush();
pw.close();
}
return null;
}
}
<3>struts.xml配置
<action name="AjaxindexAction" class="com.dreamers.login.AjaxindexAction">
</action>
以上代码是小生根据另一位兄台改的，对此十分感谢。先前他是用Servlet实现的，我改成了action实现。如有需要请参考链接：
http://blog.163.com/sean_zwx/blog/static/16903275520111222590736/