function URLEncode(unencodedValue)
{
	// The Javascript escape and unescape functions do not correspond
	// with what browsers actually do...
	var SAFECHARS = "0123456789" +					// Numeric
					"ABCDEFGHIJKLMNOPQRSTUVWXYZ" +	// Alphabetic
					"abcdefghijklmnopqrstuvwxyz" +
					"-_.!~*'()";					// RFC2396 Mark characters
	var HEX = "0123456789ABCDEF";

	var plaintext = unencodedValue;
	var encoded = "";
	for (var i = 0; i < plaintext.length; i++ ) {
		var ch = plaintext.charAt(i);
	    if (ch == " ") {
		    encoded += "+";				// x-www-urlencoded, rather than %20
		} else if (SAFECHARS.indexOf(ch) != -1) {
		    encoded += ch;
		} else {
		    var charCode = ch.charCodeAt(0);
			if (charCode > 255) {
			    alert( "Unicode Character '" 
                        + ch 
                        + "' cannot be encoded using standard URL encoding.\n" +
				          "(URL encoding only supports 8-bit characters.)\n" +
						  "A space (+) will be substituted." );
				encoded += "+";
			} else {
				encoded += "%";
				encoded += HEX.charAt((charCode >> 4) & 0xF);
				encoded += HEX.charAt(charCode & 0xF);
			}
		}
	} // for

	return encoded;
};

function URLDecode(encodedValue)
{
   // Replace + with ' '
   // Replace %xx with equivalent character
   // Put [ERROR] in output if %xx is invalid.
   var HEXCHARS = "0123456789ABCDEFabcdef"; 
   var encoded = encodedValue
   var plaintext = "";
   var i = 0;
   while (i < encoded.length) {
       var ch = encoded.charAt(i);
	   if (ch == "+") {
	       plaintext += " ";
		   i++;
	   } else if (ch == "%") {
			if (i < (encoded.length-2) 
					&& HEXCHARS.indexOf(encoded.charAt(i+1)) != -1 
					&& HEXCHARS.indexOf(encoded.charAt(i+2)) != -1 ) {
				plaintext += unescape( encoded.substr(i,3) );
				i += 3;
			} else {
				alert( 'Bad escape combination near ...' + encoded.substr(i) );
				plaintext += "%[ERROR]";
				i++;
			}
		} else {
		   plaintext += ch;
		   i++;
		}
	} // while
   return plaintext;
};
jQuery.extend({
/**
* Returns get parameters.
*
* If the desired param does not exist, null will be returned
*
* @example value = $.getURLParam("paramName");
*/ 
 getURLParameter: function(strParamName){
	  var strReturn = "";
	  var strHref = window.location.href;
	  var bFound=false;
	  
	  var cmpstring = strParamName + "=";
	  var cmplen = cmpstring.length;

	  if ( strHref.indexOf("?") > -1 ){
	    var strQueryString = strHref.substr(strHref.indexOf("?")+1);
	    var aQueryString = strQueryString.split("&");
	    for ( var iParam = 0; iParam < aQueryString.length; iParam++ ){
	      if (aQueryString[iParam].substr(0,cmplen)==cmpstring){
	        var aParam = aQueryString[iParam].split("=");
	        strReturn = URLDecode(aParam[1]);//should decode url string
	        bFound=true;
	        break;
	      }
	      
	    }
	  }
	  if (bFound==false) return null;
	  return strReturn;
	}
});
jQuery.extend({
	setURLParameter:function(url,parameterName,parameterValue){
		return url+"?"+URLEncode(parameterName)+"="+URLEncode(parameterValue);
	}
	
});
jQuery.extend({
	appendURLParameter:function(url,parameterName,parameterValue){
		return url+"&"+URLEncode(parameterName)+"="+URLEncode(parameterValue);
	}

});