function setupParameters() {
          var parameters = new Object();
          if(window.location.search) {
              var paramArray = window.location.search.substr(1).split('&');
              var length = paramArray.length;
              for (var index = 0;index <length; index++ ) {
                  var param = paramArray[index].split('=');
                  var name = param[0];
                  var value =
                      typeof param[1] == "string"
                      ? decodeURIComponent(param[1].replace(/\+/g, ' '))
                      : null;
                  parameters[name] = value;
              }
          }
          window.location.parameters = parameters;
		  
      }
	  
function getParameter(name)	{
    setupParameters();
    return window.location.parameters[name];
	}

function setParameter(name, newVal)	{
   	 //alert(window.location.search);
	 var pattern = new RegExp(name);
	 var newString = window.location.search.replace(pattern, newVal);
	 //alert(newString);
	window.location.search = newString;
	}
	
function requiredLink (url) {
	var qs = (typeof(window.location.search)=="undefined")? "" : window.location.search;
	document.location.href = url + qs;
}