Ajax与后台的交互
Ajax Java 交互
jsp代码
<%@ 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 'index.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">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<script type="text/javascript">
var xmlHttprequest = null;
function ajax(){
if(window.ActiveXObject){
xmlHttprequest = new ActiveXObject("Microsoft.XMLHTTP");
}else if(window.XMLHttpRequest){
xmlHttprequest = new XMLHttpRequest;
}
if(xmlHttprequest != null){
var v1 = document.getElementById("v1").value;
var v2 = document.getElementById("v2").value;
xmlHttprequest.open("post","ajaxServlet.do",true);
xmlHttprequest.onreadystatechange=ajaxCallBack;
xmlHttprequest.setRequestHeader("Content-type",
"application/x-www-form-urlencoded");
xmlHttprequest.send("v1="+v1+"&v2="+v2);
}
}
function ajaxCallBack(){
if(xmlHttprequest.readyState == 4){
if(xmlHttprequest.status == 200){
var responseText = xmlHttprequest.responseText;
document.getElementById("div").innerHTML = responseText;
}
}else{
document.getElementById("div").innerHTML="服务器出现错误！";
}
}
</script>
<body>
<input type="button" value="click here" onclick="ajax();" />
<input type="text" id="v1"></input>
<input type="text" id="v2"></input>
<div id="div"></div>
</body>
</html>
java后台
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 AjaxServlet extends HttpServlet{
/**
*
*/
private static final long serialVersionUID = 1733653367006626421L;
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
PrintWriter out = resp.getWriter();
String v1 = req.getParameter("v1");
String v2 = req.getParameter("v2");
out.print(v1+v2+"dadasdsadsa");
out.flush();
}
}
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <servlet> <servlet-name>ajax</servlet-name> <servlet-class>AjaxServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>ajax</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> </web-app>
