var xmlHttp = createXmlHttpRequestObject();

function createXmlHttpRequestObject() 
{
  var xmlHttp;
  try
  {
    xmlHttp = new XMLHttpRequest();
  }
  catch(e)
  {
    var XmlHttpVersions = new Array("MSXML2.XMLHTTP.6.0",
                                    "MSXML2.XMLHTTP.5.0",
                                    "MSXML2.XMLHTTP.4.0",
                                    "MSXML2.XMLHTTP.3.0",
                                    "MSXML2.XMLHTTP",
                                    "Microsoft.XMLHTTP");
    for (var i=0; i<XmlHttpVersions.length && !xmlHttp; i++) 
    {
      try 
      { 
        xmlHttp = new ActiveXObject(XmlHttpVersions[i]);
      } 
      catch (e) {}
    }
  }
  if (!xmlHttp)
    alert("Error creating the XMLHttpRequest object.");
  else 
    return xmlHttp;
}

function process(id_good)
{
  if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0)
  {
        xmlHttp.open("GET", "js/php_cart.php?id=" + id_good, true);
        xmlHttp.onreadystatechange = handleServerResponse;
        xmlHttp.send(null);
  }
  else
  {
        setTimeout('process()',800);
  }
}

function empty()
{
  if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0)
  {
        xmlHttp.open("GET", "js/empty_cart.php", true);
        xmlHttp.onreadystatechange = handleServerResponse;
        xmlHttp.send(null);
  }
  else
  {
        setTimeout('process()',800);
  }
}

function handleServerResponse() 
{
  if (xmlHttp.readyState == 4) 
  {
    if (xmlHttp.status == 200) 
    {
      response = xmlHttp.responseText;
      helloMessage = response;
      document.getElementById("divtt").innerHTML =  helloMessage;
    } 
    else 
    {
      alert("There was a problem accessing the server: " + xmlHttp.statusText);
    }
  }
}