c# excel转datatable

1. 安装nuget包 NPOI

 

 

2. 读取Excel到DataTable中

/// <summary>  
/// 将excel导入到datatable  
/// </summary>  
/// <param name="filePath">excel路径</param>  
/// <param name="isColumnName">第一行是否是列名</param>  
/// <returns>返回datatable</returns>  
public static DataTable ExcelToDataTable(string filePath, bool isColumnName)
{
    DataTable dataTable = null;
    FileStream fs = null;
    DataColumn column = null;
    DataRow dataRow = null;
    IWorkbook workbook = null;
    ISheet sheet = null;
    IRow row = null;
    ICell cell = null;
    int startRow = 0;
    try
    {
        using (fs = System.IO.File.OpenRead(filePath))
        {
            // 2007版本  
            if (filePath.IndexOf(".xlsx") > 0)
                workbook = new XSSFWorkbook(fs);
            // 2003版本  
            else if (filePath.IndexOf(".xls") > 0)
                workbook = new HSSFWorkbook(fs);

            if (workbook != null)
            {
                sheet = workbook.GetSheetAt(0);//读取第一个sheet，当然也可以循环读取每个sheet  
                dataTable = new DataTable();
                if (sheet != null)
                {
                    int rowCount = sheet.LastRowNum;//总行数  
                    if (rowCount > 0)
                    {
                        IRow firstRow = sheet.GetRow(0);//第一行  
                        int cellCount = firstRow.LastCellNum;//列数  

                        //构建datatable的列  
                        if (isColumnName)
                        {
                            startRow = 1;//如果第一行是列名，则从第二行开始读取  
                            for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                            {
                                cell = firstRow.GetCell(i);
                                if (cell != null)
                                {
                                    if (cell.StringCellValue != null)
                                    {
                                        column = new DataColumn(cell.StringCellValue);
                                        dataTable.Columns.Add(column);
                                    }
                                }
                            }
                        }
                        else
                        {
                            for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
                            {
                                column = new DataColumn("column" + (i + 1));
                                dataTable.Columns.Add(column);
                            }
                        }

                        //填充行  
                        for (int i = startRow; i <= rowCount; ++i)
                        {
                            row = sheet.GetRow(i);
                            if (row == null) continue;

                            dataRow = dataTable.NewRow();
                            for (int j = row.FirstCellNum; j < cellCount; ++j)
                            {
                                cell = row.GetCell(j);
                                if (cell == null)
                                {
                                    dataRow[j] = "";
                                }
                                else
                                {
                                    //CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)  
                                    switch (cell.CellType)
                                    {
                                        case CellType.Blank:
                                            dataRow[j] = "";
                                            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)
                                                dataRow[j] = cell.DateCellValue;
                                            else
                                                dataRow[j] = cell.NumericCellValue;
                                            break;
                                        case CellType.String:
                                            dataRow[j] = cell.StringCellValue;
                                            break;
                                    }
                                }
                            }
                            dataTable.Rows.Add(dataRow);
                        }
                    }
                }
            }
        }
        return dataTable;
    }
    catch (Exception ex)
    {
        if (fs != null)
        {
            fs.Close();
        }
        throw ex;
    }
}