非常简单的Ajax请求实例附源码

!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
html xmlns="http://www.w3.org/1999/xhtml">
head>
 meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 title>简单的Ajax请求/title>
 script type="text/javascript">
  var xmlHttp;
  // 创建XMLHttpRequest对象
  function createXMLHttpRequest() {
   if (window.ActiveXObject) {
    xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
   }
   else if (window.XMLHttpRequest) {
    xmlHttp = new XMLHttpRequest();
   }
  }
  // 整合url参数
  function createQueryString() {
   var name = document.getElementById("txtName").value;
   var sex = document.getElementById("txtSex").value;
   var birthday = document.getElementById("txtBirthday").value;
   var queryString = "Name=" + encodeURIComponent(name) + "Sex=" + encodeURIComponent(sex) + "Birthday=" + encodeURIComponent(birthday);
   return queryString;
  }
  // 按照Get方式传递参数
  function doRequestUsingGET() {
   createXMLHttpRequest();
   var queryString = "AjaxServer.ashx?";
   queryString = queryString + createQueryString() + "timeStamp=" + new Date().getTime();
   xmlHttp.onreadystatechange = handleStateChange;
   xmlHttp.open("GET", queryString, true);
   xmlHttp.send(null);
  }
  // 按POST方式传递参数
  function doRequestUsingPOST() {
   createXMLHttpRequest();
   var url = "AjaxServer.ashx?timeStamp=" + new Date().getTime();
   var queryString = createQueryString();
   xmlHttp.open("POST", url, true);
   xmlHttp.onreadystatechange = handleStateChange;
   xmlHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;");
   xmlHttp.send(queryString);
  }
  // 回调函数
  function handleStateChange() {
   if (xmlHttp.readyState == 4) {
    if (xmlHttp.status == 200) {
     parseResults();
    }
   }
  }
  // 处理服务器响应内容
  function parseResults() {
   var responseDiv = document.getElementById("serverResponse");
   if (responseDiv.hasChildNodes()) {
    responseDiv.removeChild(responseDiv.childNodes[0]);
   }
   var responseText = document.createTextNode(xmlHttp.responseText);
   responseDiv.appendChild(responseText);
  }
 /script>
/head>
body>
 form action="#">
 h2>输入你的名字,性别,生日：/h2>
 table>
  tr>td>名字：/td>td>input type="text" id="txtName" />/td>/tr>
  tr>td>性别：/td>td>input type="text" id="txtSex" />/td>/tr>
  tr>td>生日：/td>td>input type="text" id="txtBirthday" />/td>
  /tr>
 /table>
 input type="button" value="用Get方式传参数" onclick="doRequestUsingGET();"/>
 br />br />
 input type="button" value="用POST方式传参数" onclick="doRequestUsingPOST();"/>
 /form>
 br />
 h3>服务器响应内容：/h3>
 div id="serverResponse">/div>
/body>
/html>