public IList<Core.Business.VirtualLabDataAnnex> GetAllVirtualLabDataAnnex()
        {
            IList<Core.Business.VirtualLabDataAnnex> virtualLabDataAnnexlist = new List<Core.Business.VirtualLabDataAnnex>();
            SqlServerUtility sql = new SqlServerUtility();

            SqlDataReader reader = sql.ExecuteSPReader("usp_SelectVirtualLabDataAnnexsAll");

            if(reader != null)
            {
                while(reader.Read())
                {
                    Core.Business.VirtualLabDataAnnex virtualLabDataAnnex = new Core.Business.VirtualLabDataAnnex();

                    if (!reader.IsDBNull(0)) virtualLabDataAnnex.Id = reader.GetGuid(0);
                    if (!reader.IsDBNull(1)) virtualLabDataAnnex.ContentID = reader.GetGuid(1);
                    if (!reader.IsDBNull(2)) virtualLabDataAnnex.Name = reader.GetString(2);
                    if (!reader.IsDBNull(3)) virtualLabDataAnnex.Url = reader.GetString(3);

                    virtualLabDataAnnex.MarkOld();
                    virtualLabDataAnnexlist.Add(virtualLabDataAnnex);
                }
                reader.Close();
            }
            return virtualLabDataAnnexlist;
        }
        public Core.Business.VirtualLabDataAnnex Select(Guid id)
        {
            SqlServerUtility sql = new SqlServerUtility();

            sql.AddParameter("@ID", SqlDbType.UniqueIdentifier, id);
            SqlDataReader reader = sql.ExecuteSPReader("usp_SelectVirtualLabDataAnnex");

            if (reader != null && !reader.IsClosed && reader.Read())
            {
                Core.Business.VirtualLabDataAnnex virtualLabDataAnnex = new Core.Business.VirtualLabDataAnnex();

                if (!reader.IsDBNull(0)) virtualLabDataAnnex.Id = reader.GetGuid(0);
                if (!reader.IsDBNull(1)) virtualLabDataAnnex.ContentID = reader.GetGuid(1);
                if (!reader.IsDBNull(2)) virtualLabDataAnnex.Name = reader.GetString(2);
                if (!reader.IsDBNull(3)) virtualLabDataAnnex.Url = reader.GetString(3);

                reader.Close();
                return virtualLabDataAnnex;
            }
            else
            {
                if (reader != null && !reader.IsClosed)
                    reader.Close();

                return null;
            }
        }
        public IList<Core.Business.VirtualLabDataAnnex> SelectByContentID(Guid IsonID)
        {
            IList<Core.Business.VirtualLabDataAnnex> virtualLabDataAnnexlist = new List<Core.Business.VirtualLabDataAnnex>();
            SqlServerUtility sql = new SqlServerUtility();
            string sqlstr = "SELECT * FROM [dbo].[VirtualLabDataAnnex] where contentID='";
            sqlstr += IsonID.ToString()+"'";
            SqlDataReader reader = sql.ExecuteSqlReader(sqlstr);

            if (reader != null)
            {
                while (reader.Read())
                {
                    Core.Business.VirtualLabDataAnnex virtualLabDataAnnex = new Core.Business.VirtualLabDataAnnex();

                    if (!reader.IsDBNull(0)) virtualLabDataAnnex.Id = reader.GetGuid(0);
                    if (!reader.IsDBNull(1)) virtualLabDataAnnex.ContentID = reader.GetGuid(1);
                    if (!reader.IsDBNull(2)) virtualLabDataAnnex.Name = reader.GetString(2);
                    if (!reader.IsDBNull(3)) virtualLabDataAnnex.Url = reader.GetString(3);

                    virtualLabDataAnnex.MarkOld();
                    virtualLabDataAnnexlist.Add(virtualLabDataAnnex);
                }
                reader.Close();
            }
            return virtualLabDataAnnexlist;
        }