function getElementLeft(elem) {
 xPos = elem.offsetLeft;
 tempEl = elem.offsetParent;
 while (tempEl != null) {
  xPos += tempEl.offsetLeft;
  tempEl = tempEl.offsetParent;
 }
 return xPos;
}

function getElementTop(elem) {
 yPos = elem.offsetTop;
 tempEl = elem.offsetParent;
 while (tempEl != null) {
  yPos += tempEl.offsetTop;
  tempEl = tempEl.offsetParent;
 }
 return yPos;
}

function getHTTPObject()
{
 if (window.XMLHttpRequest){
   return new XMLHttpRequest();
 }else if (window.ActiveXObject){
   return new ActiveXObject("Microsoft.XMLHTTP");
 }else{
  alert("Your browser does not support AJAX.");
  return null;}
}

function isNullOrEmpty(str)
{
 if(str == "")
  return true;
 else if(""+str == "undefined")
  return true;
 else if(""+str == "null")
  return true;
 else
  return false;
  
}

function isNull(str, text)
{
 if(isNullOrEmpty(str))
  return text;
 else
  return str;
}