Ajax_JavaScript实现交互

最新推荐文章于 2025-09-12 14:04:02 发布

转载最新推荐文章于 2025-09-12 14:04:02 发布 · 62 阅读

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CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/itgotime/p/9880140.html

文章标签：

#javascript #java #web.xml #ViewUI

jsp页面：

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Ajax</title>
<script type="text/javascript">
function ok()
{
   var xmlhttp;
   if(window.XMLHttpRequest)
       {
       //非ie
       xmlhttp=new XMLHttpRequest();

       }
   else if(window.ActiveXObject){
       try{
           //ie
           xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
       }catch(e){
           xmlhttp=new ActiveXObject("Msxml2.XMLHTTP");
       }
   }
   //回调函数
   xmlhttp.onreadystatechange=function(){
       //alert(xmlhttp.readyState);
       if(4==xmlhttp.readyState)
           {
           //alert(msgWelcome);
           if(200==xmlhttp.status)
               {
               //返回值

               var msgWelcome=xmlhttp.responseText;
               var msg=document.getElementById("msg");
               msg.innerHTML=msgWelcome;

               }
           }
   }
   //请求：
   xmlhttp.open("get","http://localhost:8080/AjaxTest/HelloWorld",true);
   //http头：
   xmlhttp.setRequestHeader('Content-type','application/x-www-form-urlencoded');
   //发送请求
   xmlhttp.send(null);
   }

</script>
</head>
<body>
<span id='msg'></span><br>
<input type="button" onclick="ok();" value="单击"/>
</body>
</html>

servlet:

package com.god.service;

import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;

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 HelloWorld
*/
@WebServlet("/HelloWorld")
public class HelloWorld extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
* @see HttpServlet#HttpServlet()
*/
public HelloWorld() {
super();
// TODO Auto-generated constructor stub
}

   /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       response.setContentType("text/plain;charset=UTF-8");
       PrintWriter out=response.getWriter();
       out.write("now:"+getCurrentDateAndTime());
       //System.out.println("xxx");
   }

   private String getCurrentDateAndTime() {
       String currentDate="";
       //日期格式
       SimpleDateFormat format1=new SimpleDateFormat("yyy'-'MM'-'dd'-'hh'-'mm'-'ss");
       format1.setLenient(false);
       currentDate=format1.format(new Date());
       //
       return currentDate;
   }

   /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       // TODO Auto-generated method stub
       doGet(request, response);
   }

}
web.xml:

<servlet>
<servlet-name>HelloWorld</servlet-name>
<servlet-class>com.god.service.HelloWorld</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>HelloWorld</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>

转载于:https://www.cnblogs.com/itgotime/p/9880140.html