C#从excel中将数据导出到datatable

 #region 从excel中将数据导出到datatable
    /// <summary>
    /// 读取excel 默认第一行为标头
    /// </summary>
    /// <param name="strFileName">excel文档路径</param>
    /// <returns></returns>
    public static DataTable ImportExceltoDt(string strFileName)
    {
        DataTable dt = new DataTable();
        IWorkbook wb;
        using (FileStream file = new FileStream(strFileName, FileMode.Open, FileAccess.Read))
        {

            wb = WorkbookFactory.Create(file);
        }
        ISheet sheet = wb.GetSheetAt(0);
        dt = ImportDt(sheet, 0, true);
        return dt;
    }
 /// <summary>
    /// 将制定sheet中的数据导出到datatable中
    /// </summary>
    /// <param name="sheet">需要导出的sheet</param>
    /// <param name="HeaderRowIndex">列头所在行号，-1表示没有列头</param>
    /// <returns></returns>
    /// 



    static DataTable ImportDt(ISheet sheet, int HeaderRowIndex, bool needHeader)
    {
        DataTable table = new DataTable();
        IRow headerRow;
        int cellCount;
        try
        {
            if (HeaderRowIndex < 0 || !needHeader)
            {
                headerRow = sheet.GetRow(0);
                cellCount = headerRow.LastCellNum;

                for (int i = headerRow.FirstCellNum; i <= cellCount; i++)
                {
                    DataColumn column = new DataColumn(Convert.ToString(i));
                    table.Columns.Add(column);
                }
            }
            else
            {
                headerRow = sheet.GetRow(HeaderRowIndex);
                cellCount = headerRow.LastCellNum;

                for (int i = headerRow.FirstCellNum; i <= cellCount; i++)
                {
                    if (headerRow.GetCell(i) == null)
                    {
                        if (table.Columns.IndexOf(Convert.ToString(i)) > 0)
                        {
                            DataColumn column = new DataColumn(Convert.ToString("重复列名" + i));
                            table.Columns.Add(column);
                        }
                        else
                        {
                            DataColumn column = new DataColumn(Convert.ToString(i));
                            table.Columns.Add(column);
                        }

                    }
                    else if (table.Columns.IndexOf(headerRow.GetCell(i).ToString()) > 0)
                    {
                        DataColumn column = new DataColumn(Convert.ToString("重复列名" + i));
                        table.Columns.Add(column);
                    }
                    else
                    {
                        DataColumn column = new DataColumn(headerRow.GetCell(i).ToString());
                        table.Columns.Add(column);
                    }
                }
            }
            int rowCount = sheet.LastRowNum;
            for (int i = (HeaderRowIndex + 1); i <= sheet.LastRowNum; i++)
            {
                try
                {
                    IRow row;
                    if (sheet.GetRow(i) == null)
                    {
                        row = sheet.CreateRow(i);
                    }
                    else
                    {
                        row = sheet.GetRow(i);
                    }

                    DataRow dataRow = table.NewRow();

                    for (int j = row.FirstCellNum; j <= cellCount; j++)
                    {
                        try
                        {
                            if (row.GetCell(j) != null)
                            {
                                switch (row.GetCell(j).CellType)
                                {
                                    case CellType.String:
                                        string str = row.GetCell(j).StringCellValue;
                                        if (str != null && str.Length > 0)
                                        {
                                            dataRow[j] = str.ToString();
                                        }
                                        else
                                        {
                                            dataRow[j] = null;
                                        }
                                        break;
                                    case CellType.Numeric:
                                        if (DateUtil.IsCellDateFormatted(row.GetCell(j)))
                                        {
                                            dataRow[j] = DateTime.FromOADate(row.GetCell(j).NumericCellValue);
                                        }
                                        else
                                        {
                                            dataRow[j] = Convert.ToDouble(row.GetCell(j).NumericCellValue);
                                        }
                                        break;
                                    case CellType.Boolean:
                                        dataRow[j] = Convert.ToString(row.GetCell(j).BooleanCellValue);
                                        break;
                                    case CellType.Error:
                                        dataRow[j] = ErrorEval.GetText(row.GetCell(j).ErrorCellValue);
                                        break;
                                    case CellType.Formula:
                                        switch (row.GetCell(j).CachedFormulaResultType)
                                        {
                                            case CellType.String:
                                                string strFORMULA = row.GetCell(j).StringCellValue;
                                                if (strFORMULA != null && strFORMULA.Length > 0)
                                                {
                                                    dataRow[j] = strFORMULA.ToString();
                                                }
                                                else
                                                {
                                                    dataRow[j] = null;
                                                }
                                                break;
                                            case CellType.Numeric:
                                                dataRow[j] = Convert.ToString(row.GetCell(j).NumericCellValue);
                                                break;
                                            case CellType.Boolean:
                                                dataRow[j] = Convert.ToString(row.GetCell(j).BooleanCellValue);
                                                break;
                                            case CellType.Error:
                                                dataRow[j] = ErrorEval.GetText(row.GetCell(j).ErrorCellValue);
                                                break;
                                            default:
                                                dataRow[j] = "";
                                                break;
                                        }
                                        break;
                                    default:
                                        dataRow[j] = "";
                                        break;
                                }
                            }
                        }
                        catch (Exception exception)
                        {

                        }
                    }
                    table.Rows.Add(dataRow);
                }
                catch (Exception exception)
                {
                    //wl.WriteLogs(exception.ToString());
                }
            }
        }
        catch (Exception exception)
        {
            //wl.WriteLogs(exception.ToString());
        }
        return table;
    }

    #endregion