function getXhr(){
var xhr = null; 
	if(window.XMLHttpRequest) // Firefox et autres
		xhr = new XMLHttpRequest(); 
	else 
		if(window.ActiveXObject){ // Internet Explorer 
			try {
				xhr = new ActiveXObject("Msxml2.XMLHTTP");
				} catch (e) {
				xhr = new ActiveXObject("Microsoft.XMLHTTP");
			}
		}
		else { // XMLHttpRequest non supporté par le navigateur 
			alert("Votre navigateur ne supporte pas les objets XMLHTTPRequest..."); 
			xhr = false; 
	} 
	return xhr
}
			

function go(page,cat_id,os,order,div){
	var xhr = getXhr()
	xhr.onreadystatechange = function(){
		if(xhr.readyState == 4 && xhr.status == 200){
			document.getElementById(div).innerHTML=xhr.responseText;
		}
	}
	xhr.open("POST",page,true);
	xhr.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
	if (order != "")
	{
	xhr.send("cat_id="+cat_id+"&os="+os+"&order="+order+"&xml=true");
	}
	else
	{
	xhr.send("cat_id="+cat_id+"&os="+os+"&order=&xml=true");
	}
}