GridView:Sorting & Paging Using Generics And Nullable Datatype Function Of C# GetValueOrDefault()

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

/// <summary>
/// Summary description for Utility
/// </summary>
namespace SortingAndPaging
{

public class Utility
{
    public enum SortOrder
    {
        Asc,
        Desc

    }
}

}