TA的每日心情 | 开心 2021-3-12 23:18 |
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签到天数: 2 天 [LV.1]初来乍到
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Ajax异步请求,Servlet产生随机数据,HTML页面无刷新显示。
运行环境:jdk1.5+tomcat 5.5
一、ajaxServlet.java
- package com;
- 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;
- import java.util.Random;
- public class ajaxServlet extends HttpServlet{
- private static final String CONTENT_TYPE="text/xml; charset=gb2312";
- public void init() throws ServletException{}
- public void doGet(HttpServletRequest request,HttpServletResponse response)
- throws ServletException,IOException{
- response.setContentType(CONTENT_TYPE);
- response.setHeader("Cache-Control","no-cache");
- response.setHeader("Pragma","no-cache");
- response.setDateHeader("Expires",0);
- PrintWriter out=response.getWriter();
- String action=request.getParameter("action");
- if(("send").equals(action)){
- Random random = new Random();
- String AA=Integer.toString(Math.abs(random.nextInt()));
- String BB=Integer.toString(Math.abs(random.nextInt()));
- String CC=Integer.toString(Math.abs(random.nextInt()));
- String DD=Integer.toString(Math.abs(random.nextInt()));
- StringBuffer sb=new StringBuffer();
- sb.append(AA); sb.append("@@@");
- sb.append(BB); sb.append("@@@");
- sb.append(CC); sb.append("@@@");
- sb.append(DD);
- out.write(sb.toString());
- out.close();
- } }}
复制代码
二、testajax.html
<html>
<head>
<title>AJAX.html</title>
</head>
<script type="text/javascript">- function getResult(){
- var url = "/Tajax/AajaxServlet?action=send";
- if (window.XMLHttpRequest) {
- req = new XMLHttpRequest();
- }else if (window.ActiveXObject){
- req = new ActiveXObject("Microsoft.XMLHTTP");
- }
- if(req){
- req.open("GET",url, true);
- req.onreadystatechange = complete;
- req.send(null);
- }
- }
- /*分析返回的文本文档*/
- function complete(){
- if (req.readyState == 4) {
- if (req.status == 200) {
- // alert(req.responseText);
- var strResult = unescape(req.responseText);
- var arrResult = strResult.split("@@@");
- RemoveRow(); //删除以前的数据.
- num1 = arrResult[0]; //字段num1的值
- num2 = arrResult[1]; //字段num2的值
- num3 = arrResult[2];
- num4 = arrResult[3];
- row1= tb.insertRow();
- cell1 = row1.insertCell();
- cell1.innerText = num1;
- cell2 = row1.insertCell();
- cell2.innerText = num2;
- row2= tb.insertRow();
- cell3 = row2.insertCell();
- cell3.innerText = num3;
- cell4 = row2.insertCell();
- cell4.innerText = num4;
- } else {
- alert("There was a problem with the request.");
- }
- }
- }
- function RemoveRow(){//保留第一行表头,其余数据均删除.
- var iRows = tb.rows.length;
- for(var i=0;i< iRows-1;i++){
- tb.deleteRow(1);
- }
- }
- function MyShow(){//2秒自动刷新一次,2秒取得一次数据.
- timer = window.setInterval("getResult()",2000);
- }
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</script> <body onload="MyShow()">
<table width="47%" height="23" border="0" cellpadding="1" cellspacing="0" id="tb">
<tr><td>代码</td>
<td>价格</td>
</tr>
</table> <form>
<p>输入股票代码:
<input type="text" size="14" name="phone" id="phone"/>
</p>
<p>你交易的数量:</p>
<p><textarea name="order" rows="6" cols="50" id="order"></textarea></p>
<p><input type="submit" value="提交" id="submit" /></p>
</form> </body>
三、web.xml <?xml version="1.0" encoding="ISO-8859-1"?> <web-app xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
version="2.4"> <display-name>Welcome to Tomcat</display-name>
<description>
Welcome to Tomcat
</description> <servlet>
<servlet-name>AajaxServlet</servlet-name>
<servlet-class>com.ajaxServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>AajaxServlet</servlet-name>
<url-pattern>/AajaxServlet</url-pattern>
</servlet-mapping>
</web-app>
运行图: 
源码下载:http://file.javaxxz.com/2014/10/13/004938234.zip |
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