var http = createRequestObject();

//  load the correct XML HTTP request object
function createRequestObject()
{
  var request_ob;
  var browser = navigator.appName;

  if (browser == "Microsoft Internet Explorer")
    request_ob = new ActiveXObject("Microsoft.XMLHTTP");
  else
    request_ob = new XMLHttpRequest();

  return request_ob;
}

function displayPosts(postid)
{
  http.open ('get', 'display_blogs.php?parent=' + postid);
  http.onreadystatechange = handleEvent;
  http.send (null);
}

function displayNewPost()
{
  http.open ('get', 'new_post.php');
  http.onreadystatechange = handleEvent;
  http.send (null);
}

function updateDisplay(start, dpp, mode, month, year)
{
  http.open ('get', 'update_display_change.php?start_pos=' + start + '&dpp=' + dpp + '&mode=' + mode + '&mon=' + month + '&yr=' + year);
  http.onreadystatechange = handleEvent;
  http.send (null);
}

function handleEvent()
{
  if (http.readyState == 4)
  {
    var response = http.responseText;
    document.getElementById('content').innerHTML = response;
  }
}