text: public String FormatAsString(){if (IsWholeColumnReference()){returnCellReference.ConvertNumToColString(_firstCell.Col)+ ":" +CellReference.ConvertNumToColString(_lastCell.Col);}StringBuilder sb = new StringBuilder(32);sb.Append(_firstCell.FormatAsString());if (!_isSingleCell){sb.Append(CELL_DELIMITER);if (_lastCell.SheetName == null){sb.Append(_lastCell.FormatAsString());}else{_lastCell.AppendCellReference(sb);}}return sb.ToString();}