var xmlHttp;
function getHttpObject()
{
    try
    {
        // Firefox, Opera 8.0+, Safari
                xmlHttp=new XMLHttpRequest();
    }
    catch (e)
    {
        // Internet Explorer
        try
        {
            xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch (e)
        {
            try
            {
                xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
            }
            catch (e)
            {
                alert("Your browser does not support AJAX!");
                return false;
            }
        }
    }
    return xmlHttp;
}



function Addcart(code)
{
	req = getHttpObject();
    	req.onreadystatechange=addcartResponse;
    	var url = "user/Addcart.php";
    	req.open( "POST", url, true );
    	req.setRequestHeader("Content-type","application/x-www-form-urlencoded");     	
   		var postparam  = "code="+code;
    	req.send( postparam );
}
function addcartResponse()
{
	if( req.readyState==4 || req.readyState=="complete" )
    	{
    		alert(req.responseText);
    	}
}