var xmlHttp;

function vytvorXMLHttpRequest(){
  if(window.ActiveXObject){
    xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
  }
  else if (window.XMLHttpRequest){
    xmlHttp = new XMLHttpRequest();
  }
}

function reagovat(adresa,url){
  vytvorXMLHttpRequest();
  xmlHttp.onreadystatechange = zpracujZmenuStavu;
  xmlHttp.open("GET", adresa + "js/diskusia_form.php?adresa=" + url, true);
  xmlHttp.send(null);
}

function zpracujZmenuStavu(){
  if(xmlHttp.readyState == 4){
    if(xmlHttp.status == 200){
        document.getElementById("diskusia_form").innerHTML = xmlHttp.responseText;
    }
  }
}