function startRequest()
{
  if(XMLHttpRequestObject){
    var btn1 = document.getElementById("btn1");
    btn1.disabled = true;
    XMLHttpRequestObject.open("GET", "http://localhost/dane.php");
    XMLHttpRequestObject.onreadystatechange = function()
    {
      if (XMLHttpRequestObject.readyState == 4){
        if(XMLHttpRequestObject.status == 200){
          tekst = XMLHttpRequestObject.responseText;
          var pt1 = document.getElementById("pt1");
          pt1.innerHTML = tekst;
        }
        btn1.disabled = false;
      }
    }
    XMLHttpRequestObject.send(null);
  }
}