/// <summary>
		/// Переводит порядковый номер столбца в его буквенный эквивалент.
		/// </summary>
		public static string ParseColNum ( int ColNum )
		{
			StringBuilder sb = new StringBuilder ( );
			
			if ( ColNum <= 0 )  return "A";

			while ( ColNum != 0 )
			{
				sb.Append ( ( char ) ( 'A' + ( ColNum % 26 ) ) );
				ColNum /= 26;
			}

			return sb.ToString ( );
		}

return new string(sb.ToString().Reverse().ToArray());

public void SetValueCell(int row, int col, string value)
        {
            object o = WorkSheet.GetType().InvokeMember("Cells", BindingFlags.GetProperty,
                null, WorkSheet, new object[] { row, col });
            o.GetType().InvokeMember("Value", BindingFlags.SetProperty, null, o, new object[] { value });
        }

public void SetValueCell(int row, int col, string value)
        {
            object o = WorkSheet.GetType().InvokeMember("Cells", BindingFlags.GetProperty,
                null, WorkSheet, new object[] { row, col });
            o.GetType().InvokeMember("Item", BindingFlags.SetProperty, null, o, new object[] { row, col, value });
        }