/// <summary>  
    /// 写入到Excel表格文件当中，导出数据  
    /// </summary>  
    /// <param name="dt"></param>  
    /// <returns></returns>  
    public bool DataTableToExcel(DataTable dt, string DataFile)  
    {  
        bool result = false;  
        IWorkbook workbook = null;  
        FileStream fs = null;  
        IRow row = null;  
        ISheet sheet = null;  
        ICell cell = null;  
        try  
        {  
            if (dt != null && dt.Rows.Count > 0)  
            {  
                workbook = new HSSFWorkbook();  
                string NowBOPName = this.CmbBOPName.Text.Trim();  
                sheet = workbook.CreateSheet(NowBOPName);//创建一个名称为Sheet0的表  
                int rowCount = dt.Rows.Count;//行数  
                int columnCount = dt.Columns.Count;//列数  

                //把A0:C0合并为一个单元格 并赋值  
                ICell hbcell = sheet.CreateRow(0).CreateCell(0);  
                hbcell.SetCellValue(NowBOPName + "工序");  
                sheet.AddMergedRegion(new NPOI.SS.Util.CellRangeAddress(0, 0, 0, 2));

                //设置样式 居中 字体  
                ICellStyle hbstyle = workbook.CreateCellStyle();  
                hbstyle.VerticalAlignment = VerticalAlignment.Center;  
                hbstyle.Alignment = NPOI.SS.UserModel.HorizontalAlignment.Center;  
                IFont hbfont = workbook.CreateFont();  
                hbfont.FontHeight = 15 \* 20;  
                hbstyle.SetFont(hbfont);  
                hbcell.CellStyle = hbstyle;

                //设置列头  
                row = sheet.CreateRow(1);//excel第一行设为标题，第二行列头  
                for (int c = 0; c < columnCount; c++)  
                {  
                    cell = row.CreateCell(c);  
                    cell.SetCellValue(dt.Columns\[c\].ColumnName);  
                }

                //设置每行每列的单元格,  
                for (int i = 0; i < rowCount; i++)  
                {  
                    row = sheet.CreateRow(i + 2);//excel第三行开始写入数据  
                    for (int j = 0; j < columnCount; j++)  
                    {  
                        cell = row.CreateCell(j);  
                        cell.SetCellValue(dt.Rows\[i\]\[j\].ToString());  
                    }  
                }  
                using (fs = File.OpenWrite(DataFile))  
                {  
                    workbook.Write(fs);//向打开的这个xls文件中写入数据  
                    result = true;  
                }  
            }  
            return result;  
        }  
        catch (Exception ex)  
        {  
            if (fs != null)  
            {  
                fs.Close();  
            }  
            return false;  
        }  
    }

///

/// 将excel导入到datatable ///

/// excel路径
/// 第一行是否是列名
/// 返回datatable
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 = 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(1);//第二行列名  
                            int cellCount = firstRow.LastCellNum;//列数

                            //构建datatable的列  
                            if (isColumnName)  
                            {  
                                startRow = 2;//如果第一行是标题，第二行列名，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)//dataTable.Columns.Count  
                                {  
                                    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\[j - row.FirstCellNum\] = "";  
                                                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\[j - row.FirstCellNum\] = cell.DateCellValue;  
                                                else  
                                                    dataRow\[j - row.FirstCellNum\] = cell.NumericCellValue;  
                                                break;  
                                            case CellType.String:  
                                                dataRow\[j - row.FirstCellNum\] = cell.StringCellValue;  
                                                break;  
                                            case CellType.Formula:  
                                                //System.Globalization.NumberFormatInfo nfi = new System.Globalization.NumberFormatInfo();  
                                                //nfi.NumberDecimalDigits = 2;  
                                                //short format = cell.CellStyle.Format("{0:F2}", Convert.ToDouble(23, 5235);  
                                                dataRow\[j - row.FirstCellNum\] = ((float)cell.NumericCellValue);  
                                                break;  
                                        }  
                                    }  
                                }  
                                dataTable.Rows.Add(dataRow);  
                            }  
                        }  
                    }  
                }  
            }  
            return dataTable;  
        }  
        catch (Exception ex)  
        {

            if (fs != null)  
            {  
                fs.Close();  
            }  
            return null;  
        }  
    }