public virtual void DeleteRecord()
        {
            if (SelectedRecord != null)
            {
                ListChangedRecords.Remove(SelectedRecord);

                if (ListNewRecords.IndexOf(SelectedRecord) >= 0)
                {
                    ListNewRecords.Remove(SelectedRecord);
                }
                else
                {
                    ListDeletedRecords.Add(SelectedRecord);
                }
                Records.Remove(SelectedRecord);
            }
        }