<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
//创建XMLHttpRequest对象
var xmlhttp;
function createXmlHttp(){
alert("come in");
//xmlhttp=new ActiveXObject("Msxml2.XMLHTTP"); //在IE中不可以
xmlhttp=new XMLHttpRequest(); //都可以创建XMLHttpRequest
return xmlhttp;
}
xmlhttp=createXmlHttp();
alert(xmlhttp);
</script>
</head>
<body>
</body>
</html>
Ajax 学习之创建XMLHttpRequest对象------Ajax的核心
原文：http://www.cnblogs.com/hqutcy/p/5722562.html