var xmlhttp = null;

function update(id) {
    
    if (window.ActiveXObject) {
        xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    else if (window.XMLHttpRequest){
        xmlhttp = new XMLHttpRequest();
    }
    
    if (xmlhttp != null) {
        
        var url = "ip.php?inzerat="+id;              
        xmlhttp.open("GET", url, false);
        xmlhttp.send(null);
    }
    else {
        alert("Your browser does not support XMLHTTP.");
    }
}