Ajax 模糊查询的简单实现

类似于百度的搜索引擎模糊查询功能，不过百度的模糊查询功能更强大，这里简单实现下.

要实现模糊查询，首先要做的就是把SQL写好。话不多少，直接贴代码了!

JSP页面：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><base href="<%=basePath%>"><title>My JSP 'search.jsp' starting page</title><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">  <script type="text/javascript" src="prototype.js"></script><style type="text/css">body{font:11px arial;}#suggest{position:absolute;background-color:#FFFFFF;text-align: :left;border: 1px solid #000000;display: none;}</style><script type="text/javascript">function searchSuggest(){var url="Search";var txtSearch=$F("txtSearch");var pars='txtSearch='+txtSearch;var searchAjax=new Ajax.Request(url,{method:'get',  //get方式提交parameters:pars, //提交参数onComplete:processRequest});}function processRequest(req){var sobj=$("suggest");sobj.innerHTML="";var str=req.responseText.split("-");var suggest="";if(str.length>0&&str[0].length>0){for(i=0;i<str.length;i++){suggest+="<div>"+str[i]+"</div>";}sobj.innerHTML=suggest;$("suggest").style.display="block";}else{$("suggest").style.display="none";}}</script></head><body><h3>Ajax自动搜索提示</h3><div style="width:500px"><form action="" id="formSearch"><input type="text" id="txtSearch" name="txtSearch"  οnkeyup="searchSuggest()"autocomplete="off"/><input type="submit" id="cmdSerach" name="cmdSearch" value="搜索"/><br/><div id="suggest" style="width:200px"></div></form></div></body>
</html>

Sevlet类:

package servlet.ajax;import java.io.IOException;
import java.io.PrintWriter;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class Search extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {request.setCharacterEncoding("UTF-8");response.setCharacterEncoding("UTF-8");String req=request.getParameter("txtSearch");PrintWriter out = response.getWriter();SearchDao sd=new SearchDao();sd.getText(req);StringBuffer sb=sd.getText(req);out.print(sb.toString());out.flush();}
}

进行连接数据库，模糊查询的JAVA类:

package servlet.ajax;import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;public class SearchDao {public StringBuffer  getText(String req){//首先定义下连接数据的URL、用户名、密码String url="jdbc:oracle:thin:@127.0.0.1:1521:orcl";String user="scott";String password="yulei123";String sql="select ename from emp a where a.ename like ?";if(req.trim().length()==0){sql=sql+" and 1<>1";}List strList=new ArrayList();try {Class.forName("oracle.jdbc.driver.OracleDriver");Connection con=DriverManager.getConnection(url,user,password);PreparedStatement pre=con.prepareStatement(sql);pre.setString(1,"%"+req.toUpperCase().trim()+"%");ResultSet rs=pre.executeQuery();while(rs.next()){String ename=rs.getString("ename");strList.add(ename);}} catch (ClassNotFoundException e) {e.printStackTrace();} catch (SQLException e) {e.printStackTrace();}StringBuffer sb=new StringBuffer();int size=strList.size();for(int i=0;i<size;i++){sb.append((String)strList.get(i)+"-");}return sb;}
}

代码写好后，就可以在文本框输入字母后就可以模糊查询出数据了!