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

function GetParamAppendChar(href)
{
	if(href.indexOf('?') == -1)
		return "?"
	else
		return "&";
}

function Sort(sortField)
{

	var oldSortField = GetParmValue("SortField");
	var sortDir = GetParmValue("SortDirection");
	var href = window.location.href.replace("#","");

	if(sortDir != "")
		href = href.replace("SortDirection=" + sortDir ,"SortDirection=" +(sortDir=="ASC" ? "DESC":"ASC")); 	
	else
		href = href +  GetParamAppendChar(href) +  "SortDirection=ASC"
		
	if(oldSortField !="")
		href = href.replace("SortField=" + oldSortField ,"SortField=" + sortField); 	
	else
		href = href + GetParamAppendChar(href) +  "SortField=" + sortField;

	window.location.href= href;
}

function SetSortArrow()
{

	var SortField = GetParmValue("SortField");
	
	if(SortField !="")
	{
		var image =document.createElement("Img");
		image.className="SortArrow";
		image.src= "/_Layouts/SelectNutrition/Images/" + GetParmValue("SortDirection") + ".jpg";
		document.getElementById("td"+SortField).appendChild(image);
	}

}