java和Ajax异步传输

来源：互联网发布：战地3低配置优化补丁编辑：程序博客网时间：2024/04/30 16:29

利用java和Ajax做个异步传输

用到的东西：

1.prototype.js

2.org.json.jar

主要的类：

package com.shangyu.json;
import org.json.*;

public class AjaxMessageJson {

private JSONObject json = new JSONObject();

public void setMessage(String codeid, String message) {
try {
   this.json.put("codeid", codeid);
   this.json.put("message", message);
   this.json.put("text", "");
} catch (JSONException e) {

}
}

public void setMessage(String codeid, String message, String text) {
try {
   this.json.put("codeid", codeid);
   this.json.put("message", message);
   this.json.put("text", text);
} catch (JSONException e) {

}
}

public String getJsonString() {
return this.json.toString();
}
}

登录页面：

<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<html>
<head>
    <title>用户登录测试json返回数据格式</title>
    <script type="text/javascript" src="js/prototype.js"></script>
<script language="JavaScript" type="text/javascript">
<!--
var flagSubmit = false ;
function checkUserName() {
//var contextPath = "<%=request.getContextPath()%>";
//alert(contextPath);
var url = "check_login_user.jsp";//校验入口
var pars = "username=" + $('username').value;//参数
   var pars1 = "&pas=" + $('pas').value;//参数
   //组合参数
   pars+=pars1;
//异步传值
var myAjax = new Ajax.Request(url,{method: 'get', parameters: pars,onLoading:loading,onFailure:reportError,onComplete: done});
}
function loading()
{
//alert('正在调用');
}
//此方法接收返回的值做分析
function done(val) {
var valText = val.responseText;
alert(valText);
var jsonMsgObj = new JsonMsgObj(valText);
var message = jsonMsgObj.getMessage();
alert(message);
}
function reportError(request)
{
alert('Sorry. There was an error.');
}
</script>
</head>

<body>
<form action="" method="post" name="form1">
用户名：<input type="text" name="username""/>新密码:<input type="text" name="pas" onchange="checkUserName()"/><br>
<input type="button" name="button" value="发送" onclick="checkUserName()">
</form>
</body>
</html>

附工程文件下载：