function andraAntal(id, typ, isbn){
	var xmlhttp;
	if(typ=="plus"){
		var antal=parseInt(document.getElementById("cart_antal" + id).value) + 1;
		}
	if(typ=="minus"){
		var antal=parseInt(document.getElementById("cart_antal" + id).value) - 1;
		}
	if(typ=="tom"){
		var antal=0;
		}
	if(typ=="antal"){
		var antal=document.getElementById("cart_antal" + id).value;
		}
	
	
	var theurl= 'http://www.billigaboken.se/kundvagn/andraantal/' + id + '/' + antal + '/' + isbn;
	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;
				}
			}
		}	
	xmlHttp.onreadystatechange=function(){
		if(xmlHttp.readyState==4){
			if(xmlHttp.responseText=="tom"){
				document.getElementById("cart_tom").style.display="";
				document.getElementById("cart_tabell").style.display="none";
				document.getElementById("cart_lank").innerHTML="0 varor i kundvagnen";
			}else{
				var temp = xmlHttp.responseText;
				var temparr = temp.split("#-#");
				if(temparr[0]=="tomrad"){
					document.getElementById("cart_row" + id).style.display="none";
					document.getElementById("cart_urow" + id).style.display="none";
					document.getElementById("cart_lank").innerHTML=temparr[1] + " varor i kundvagnen";
					document.getElementById("cart_summa").innerHTML=temparr[2] + " kr";
					}else{
						
						document.getElementById("cart_antal" + id).value=temparr[0];
						document.getElementById("cart_belopp" + id).innerHTML=temparr[1] + " kr";
						document.getElementById("cart_summa").innerHTML=temparr[2] + " kr";
						
						if(temparr[3]=="fullt"){
							var text = "Finns endast " + temparr[0] + " i lager";
							alert(text);
						}
					}
					var fraktfritt = 400 - parseInt(temparr[2]);
					if(fraktfritt<=0){
						document.getElementById("cart_frakt").innerHTML="0 kr";
						document.getElementById("cart_fraktfritt_row").style.display="none";
					}else{
						document.getElementById("cart_frakt").innerHTML="49 kr";
						document.getElementById("cart_fraktfritt_row").style.display="";
						document.getElementById("cart_fraktfritt").innerHTML=fraktfritt + " kr";
					}
				}
			}
		}
	
	xmlHttp.open("GET",theurl,true);
	xmlHttp.send(null);
	}