C# NPOI CellType类型

CellType 类型 值
CELL_TYPE_NUMERIC 数值型 0
CELL_TYPE_STRING 字符串型 1
CELL_TYPE_FORMULA 公式型 2
CELL_TYPE_BLANK 空值 3
CELL_TYPE_BOOLEAN 布尔型 4
CELL_TYPE_ERROR 错误 5

 private static object checkVlaue(ICell cell)
        {
            object returnValue = "";
            if (cell == null)
            {
                returnValue = "";
            }
            else
            {
                ***//CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)***
                switch (cell.CellType)
                {
                    case CellType.Blank:
                        returnValue = "";
                        break;
                    case CellType.Numeric:
                        short format = cell.CellStyle.DataFormat;
                        ***//对时间格式（2015.12.5、2015/12/5、2015-12-5等）的处理***
                        if (format == 14 || format == 31 || format == 57 || format == 58 || format == 20)
                            returnValue = cell.DateCellValue.ToString(" HH:mm");
                        else
                            returnValue = cell.NumericCellValue;
                        break;
                    case CellType.String:
                        returnValue = cell.StringCellValue;
                        break;
                }
            }
            return returnValue;
        }