Ajax主要来实现局部刷新的。
这是一个项目：
AjaxTest.java(Servlet)
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
/**
* Created by Administrator on 2016/12/1.
*/
public class AjaxTest extends HttpServlet {
@Override
public void doGet(HttpServletRequest req,HttpServletResponse resp) throws ServletException,IOException {
PrintWriter out = resp.getWriter();
String name= req.getParameter("name");
if(name==null||name.equals(""))
{
out.println("please input username");
} else if(name.equals("wh")){
out.println("welcome "+name);
}else{
out.println("the user doesn't esist!");
}
}
@Override
public void doPost(HttpServletRequest req,IOException {
doGet(req,resp);
}
}
ajax.html(填写数据，展示页面)
<!DOCTYPE html>
<html lang="en">
<head>
<Meta charset="UTF-8">
<title>Title</title>
<script type="text/javascript" src="jquery-3.1.1.js"></script>
<script type="text/javascript" src="verify.js"></script>
</head>
<body>
使用ajax技术处理
<input type=text" id="input" name="name" />
<input type="button" value="校验" onclick="verify()"/>
<div id="result"></div>
</body>
</html>verify.js
function verify() {
var input = $("#input");
var username = input.val();
$.get("AjaxTest?name="+username,null,callback);
}
function callback(data){
var res=$("#result");
res.html(data);
}每点击一下按钮，就会调用verify函数，从Servlet调出数据，显示在div里。