post请求 url后面加参数 接收不到的，必须
放到send（"use"=user）形式
还要加上
xhr.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
servlet
1 package cn.itcast.controller;
2
3 import java.io.IOException;
4 import javax.servlet.ServletException;
5 import javax.servlet.annotation.WebServlet;
6 import javax.servlet.http.HttpServlet;
7 import javax.servlet.http.HttpServletRequest;
8 import javax.servlet.http.HttpServletResponse;
9
10 @WebServlet("/servlet/ServletDemo2")
11 public class ServletDemo2 extends HttpServlet {
12 private static final long serialVersionUID = 1L;
13
14 public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
15 }
16
17 public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
18 //System.out.println("ServletDemo2 doPost running");
19 String username = request.getParameter("username");
20 String password = request.getParameter("password");
21 System.out.println(username+":"+password);
22 }
23
24 }
jsp
1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
2 <html>
3 <head>
4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
5 <title>AJAX进行post方式的请求测试</title>
6 </head>
7 <body>
8 <input type="button" id="b1" name="b1" value="测试与服务器的通信"/>
9 <div id="d1">
10
11 </div>
12 <script type="text/javascript">
13
14 window.onload=function(){
15 document.getElementById("b1").onclick = function(){
16 //获取xmlhttpRequest对象
17 var xhr = createXmlHttpRequest();
18 //注册状态变化的回调函数
19 xhr.onreadystatechange = function(){
20 if (xhr.readyState == 4) {
21 if (xhr.status == 200 || xhr.status == 304) {
22 //什么都不做
23 }
24 }
25 }
26 //初始化xmlhttpRequest对象，即open
27 xhr.open("POST", "/ajaxday02/servlet/ServletDemo2?time=" + new Date().getTime());
28 //设置请求消息头，告知服务器，发送的正文数据的类型。
29 xhr.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
30 //发送数据
31 xhr.send("username=admin&password=123");
32 }
33 }
34 function createXmlHttpRequest(){
35 var xmlHttp;
36 try{ //Firefox, Opera 8.0+, Safari
37 xmlHttp=new XMLHttpRequest();
38 }catch (e){
39 try{ //Internet Explorer
40 xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
41 }catch (e){
42 try{
43 xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
44 }catch (e){}
45 }
46 }
47 return xmlHttp;
48 }
49
50 </script>
51 </body>
52 </html>
时间： 2024-12-05 14:35:34