//创建函数
function createXMLHTTP() 
{
if(window.ActiveXObject){
    req = new ActiveXObject("Microsoft.XMLHTTP");
	//alert(123);
}else if(window.ActiveXObject){
	alert(13);
    req = new ActiveXObject("Msxml2.XMLHTTP.4.0");
}else if(window.ActiveXObject){
    req = new ActiveXObject("Msxml2.XMLHTTP");
}else if(window.XMLHttpRequest){
   req = new XMLHttpRequest();
}

return req;


}
  
XMLHTTP = createXMLHTTP() ;

function warn(){
	
  if(XMLHTTP.readyState == 4){
	  
    if(XMLHTTP.status == 200){
 　   var xmlDocument = XMLHTTP.responseText;
 		//alert(xmlDocument);
 　   if(xmlDocument == "Invalid"){
	 	alert("Invalid ID or Password !");
	  }
	  if(xmlDocument == "无效的"){
		alert("无效的用户名和密码！");  
	  }	 	  
	  if(xmlDocument == "Signin"){
		alert("Sign in successfully!"); 
		location.replace(location.href);
		//alert(2);
	  }
	  if(xmlDocument == "登录成功"){
		alert("登录成功！"); 
		location.replace(location.href);
	  }
 
	}
	else
    {
 　　 alert("There is an exception occurs in the page you required which may affect your browsing the information on this page.");
 　　 alert(http.status);
    }
  }	
}