var xmlHttp;
var mapa_index = 1;

function GetXmlHttpObject() {
  var xmlhttp = null;
  try
  {
    xmlhttp=new XMLHttpRequest();
  }
  catch (e)
  {
    try
    {
      xmlhttp=new ActiveXObject("Msxml2.XMLHTTP");
    }
    catch (e)
    {
      xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
  }
  return xmlhttp;
}

function getFile(url) {
  xmlHttp = GetXmlHttpObject();
  xmlHttp.onreadystatechange = showNewText;
  xmlHttp.open("GET", url, true);
  xmlHttp.send(null);
}

function showNewText() {
  if (xmlHttp.readyState == 4)
  {
    document.getElementById('obsah').innerHTML = xmlHttp.responseText;
  }
}