function modif_panier(sens,id_champ,id_cookie,ref)
	{
	var champ=document.getElementById(id_champ);
	var value_=champ.value;

	var data     = null;
	//data = 'sens='+sens+'&champ='+id_champ+'&val='+value_+'&id_cookie='+id_cookie;
		data = 'sens='+sens+'&champ='+id_champ+'&val='+value_+'&id_cookie='+id_cookie+'&ref='+ref;

		var xhr_object = null;
		if(window.XMLHttpRequest)
			{ // Firefox
				xhr_object = new XMLHttpRequest();
			}
		else if(window.ActiveXObject)
			{ // Internet Explorer
				xhr_object = new ActiveXObject('Microsoft.XMLHTTP');
			}
		var method = 'POST';
		var filename = 'panier_.php';

		xhr_object.open(method, filename, true);
		xhr_object.onreadystatechange = function()
			{
				if(xhr_object.readyState == 4)
				{
					var tmp = xhr_object.responseText;
                    //ecriture
                    //champ.value=tmp;
                    document.location='cart.php';
				}

			}

		xhr_object.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
		xhr_object.send(data);

	}