JS+Ajax实现百度智能搜索框

来源：91美食网

首先浏览实现后的结果，输入一个a之后会出现包含a的下拉列表，当我们点击某一个的时候，搜索框中就会出现点击的值。实现所需要的主要是ajax+js。

前端search.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" 
 pageEncoding="UTF-8"%> 
<html> 
<head> 
<title>Insert title here</title> 
<script src="js/jquery.min.js"></script> 
<style type="text/css"> 
 *{ 
 margin: 0 auto; 
 padding: 0; 
 } 
 li{ 
 margin:0; 
 height: 20px; 
 width: 200px; 
 list-style: none; 
 } 
 /* #c li:HOVER{ 
 background-color: #F9F9F9; 
 } */ 
 .onmouse{ 
 background-color: #F9F9F9; 
 } 
 .outmouse{ 
 background-color:white; 
 } 
 #contain{ 
 width: 50%; 
 } 
</style> 
<!-- jquery --> 
<script type="text/javascript"> 
var xmlHttp; 
 function getMoreContents() { 
 var content=document.getElementById("keyword"); 
 if(content.value==""){ 
 ClearContent(); 
 return;//如果不设置，传到后台的是空值，所有的值都会被

输出 } xmlHttp=creatXMLHttp(); //alert(xmlHttp); //要给服务器发送数据 var url="searchServlet?keyword="+escape(content.value); xmlHttp.open("GET",url,true); xmlHttp.onreadystatechange=callback; xmlHttp.send(null); } //获取XMLHttp对象 function creatXMLHttp() { var xmlHttp; if(window.XMLHttpRequest){ xmlHttp=new XMLHttpRequest(); } if(window.ActiveXObject) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); if(!xmlHttp){ xmlHttp=new ActiveXOject("Msxml2.XMLHTTP"); } } return xmlHttp; } //获取XMLHttp对象 function callback() { if(xmlHttp.readyState==4 && xmlHttp.status==200){ var result=xmlHttp.responseText; //解析数据 var json=eval("("+result+")"); //动态显示数据，线束数据在输入框对的下面 setContent(json); } } //设置关联数据的展示 function setContent(contents) { ClearContent(); var size=contents.length; for(var i=0;i<size;i++) { var nextNode=contents[i];//json格式的第i个数据 var li =document.createElement("li"); li.onmouseover=function(){ this.className="onmouse"; document.getElementById("keyword").value=this.innerHTML; } li.onmouseout=function(){ this.className="outmouse"; } var text=document.createTextNode(nextNode); li.appendChild(text); document.getElementById("c").appendChild(li); } } //清空数据 function ClearContent() { document.getElementById("c").innerHTML=""; } //当控件失去焦点时，清空数据 function outFouce() { ClearContent(); } //获得焦点时， </script> </head> <body> <div id="contain"> <div style="height: 20px;"> <input type="text" id="keyword" style="size:50px;" onkeyup="getMoreContents()" onblur="outFouce()" onfocus="getMoreContents()"> <input type="button" id="bu" value="百度一下" style=""> </div> <div id="popDiv"> <ul id="c"> <li></li> </ul> </div> </div> </body> </html>

后台searchServlet.Java

package search; 
import java.io.IOException; 
import java.util.ArrayList; 
import java.util.List; 
import net.sf.json.JSONArray; 
import javax.servlet.ServletException; 
import javax.servlet.annotation.WebServlet; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
/** 
 * Servlet implementation class searchServlet 
 */ 
@WebServlet("/searchServlet") 
public class searchServlet extends HttpServlet { 
 private static final long serialVersionUID = 1L; 
 static List<String> datas=new ArrayList<String>(); 
 static {//假数据，模拟数据库读取 
 datas.add("ajax"); 
 datas.add("bjax"); 
 datas.add("ajaxfd"); 
 datas.add("bfvd"); 
 datas.add("dafdx"); 
 datas.add("fdax"); 
 datas.add("ahg"); 
 datas.add("ddx"); 
 } 
 /** 
 * @see HttpServlet#HttpServlet() 
 */ 
 public searchServlet() { 
 super(); 
 // TODO Auto-generated constructor stub 
 } 
 /** 
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) 
 */ 
 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
 // TODO Auto-generated method stub 
 doPost(request, response); 
 } 
 /** 
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) 
 */ 
 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
 // TODO Auto-generated method stub 
 request.setCharacterEncoding("UTF-8"); 
 response.setCharacterEncoding("UTF-8"); 
 String keyword=request.getParameter("keyword"); 
 //System.out.println(keyword); 
 List<String> listdata= getData(keyword); 
 // 返回json,以流的形式写到前台 
 response.getWriter().write(JSONArray.fromObject(listdata).toString()); 
 } 
 //获取假数据中符合条件的值 
 public List<String> getData(String keyword) 
 { 
 List<String> list=new ArrayList<String>(); 
 for(String data:datas) 
 { 
 if(data.contains(keyword)){ 
 list.add(data); 
 } 
 } 
 return list; 
 } 
}

xml配置

<span style="font-size:18px;"><strong><?xml version="1.0" encoding="UTF-8"?> 
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1"> 
 <servlet> 
 <servlet-name>searchServlet</servlet-name> 
 <servlet-class>search.searchServlet</servlet-class> 
 </servlet> 
 <servlet-mapping> 
 <servlet-name>searchServlet</servlet-name> 
 <url-pattern>/search/searchServlet</url-pattern> 
 </servlet-mapping> 
 <display-name>DropMeum</display-name> 
 <welcome-file-list> 
 <welcome-file>index.html</welcome-file> 
 <welcome-file>index.htm</welcome-file> 
 <welcome-file>index.jsp</welcome-file> 
 <welcome-file>default.html</welcome-file> 
 <welcome-file>default.htm</welcome-file> 
 <welcome-file>default.jsp</welcome-file> 
 </welcome-file-list> 
</web-app></strong></span>

目录结构

总结

以上所述是小编给大家介绍的JS+Ajax实现百度智能搜索框，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持！