function getParam(name, url){
  if (!url) url = window.location.href;
  name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");  
  var regexS = "[\\?&]"+name+"=([^&#]*)";  
  var regex = new RegExp(regexS);  
  var results = regex.exec(url.toLowerCase());  
  return (results) ?  results[1] : "";  
}