使用NPOI操作Excel(03、07)

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using NPOI.SS.UserModel;
 using NPOI.XSSF.UserModel;
 using NPOI.HSSF.UserModel;
 using System.IO;
 using System.Data;
 using NPOI.SS.Util;

 namespace Common
 {
     public class ExcelHelper : IDisposable
     {
         private string fileName = null; //文件名
         private IWorkbook workbook = null;
         private FileStream fs = null;
         private bool disposed;

         public ExcelHelper(string fileName)
         {
             this.fileName = fileName;
             disposed = false;
         }
         /// <summary>
         /// 生成Sheet对象
         /// </summary>
         /// <param name="fileName">导出Excel文件完整文件名</param>
         /// <param name="sheetName">要导入的excel的sheet的名称</param>
         /// <returns></returns>
         public ISheet GenerateSheet(string sheetName)
         {
             ISheet sheet = null;

             fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.ReadWrite);
             if (fileName.IndexOf(".xlsx") > ) // 2007版本
                 workbook = new XSSFWorkbook();
             else if (fileName.IndexOf(".xls") > ) // 2003版本
                 workbook = new HSSFWorkbook();
             if (workbook != null)
             {
                 sheet = workbook.CreateSheet(sheetName);
             }
             return sheet;
         }
         /// <summary>
         /// 将DataTable数据导入到excel中
         /// </summary>
         /// <param name="sheet">所要操作Excel的Sheet对象</param>
         /// <param name="data">要导入的数据</param>
         /// <param name="dataRowStart">数据起始行索引</param>
         /// <returns>导入数据行数(包含列名那一行)</returns>
         public int DataTableToExcel(ISheet sheet, DataTable data, int dataRowStart)
         {
             int i = ;
             int j = ;
             try
             {
                 if (sheet != null)
                 {
                     for (i = ; i < data.Rows.Count; ++i)
                     {
                         IRow row = sheet.CreateRow(dataRowStart);
                         for (j = ; j < data.Columns.Count; ++j)
                         {
                             row.CreateCell(j).SetCellValue(data.Rows[i][j].ToString());
                         }
                         ++dataRowStart;
                     }
                     workbook.Write(fs); //写入到excel
                 }
                 return dataRowStart;
             }
             catch (Exception ex)
             {
                 Console.WriteLine("Exception: " + ex.Message);
                 return -;
             }
         }

         /// <summary>
         /// 将excel中的数据导入到DataTable中
         /// </summary>
         /// <param name="sheetName">excel工作薄sheet的名称</param>
         /// <param name="dataRowStart">数据起始行索引</param>
         /// <returns>返回的DataTable</returns>
         public DataTable ExcelToDataTable(DataTable tableModel, string sheetName, int dataRowStart)
         {
             ISheet sheet = null;
             DataTable data = tableModel.Clone();
             try
             {
                 fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
                 if (fileName.IndexOf(".xlsx") > ) // 2007版本
                     workbook = new XSSFWorkbook(fs);
                 else if (fileName.IndexOf(".xls") > ) // 2003版本
                     workbook = new HSSFWorkbook(fs);

                 if (sheetName != null)
                 {
                     sheet = workbook.GetSheet(sheetName);
                     if (sheet == null) //如果没有找到指定的sheetName对应的sheet，则尝试获取第一个sheet
                     {
                         sheet = workbook.GetSheetAt();
                     }
                 }
                 else
                 {
                     sheet = workbook.GetSheetAt();
                 }
                 if (sheet != null)
                 {
                     IRow firstRow = sheet.GetRow(dataRowStart);
                     int cellCount = firstRow.LastCellNum; //一行最后一个cell的编号 即总的列数
                     //最后一列的标号
                     int rowCount = sheet.LastRowNum;
                     for (int i = dataRowStart; i <= rowCount; ++i)
                     {
                         IRow row = sheet.GetRow(i);
                         if (row == null) continue; //没有数据的行默认是null

                         DataRow dataRow = data.NewRow();
                         for (int j = row.FirstCellNum; j < cellCount; ++j)
                         {
                             if (row.GetCell(j) != null) //同理，没有数据的单元格都默认是null
                                 dataRow[j] = row.GetCell(j).ToString();
                         }
                         data.Rows.Add(dataRow);
                     }
                 }

                 return data;
             }
             catch (Exception ex)
             {
                 Console.WriteLine("Exception: " + ex.Message);
                 return null;
             }
         }
         /// <summary>
         /// 设置表头（支持单元格合并）
         /// </summary>
         /// <param name="sheet">要合并单元格所在的sheet</param>
         /// <param name="mergeArrayList">需要进行单元格合并的单元格索引数组，数组长度为4，第一个为行起始位置，第二个为行结束为止，第三个为列起始位置，第四个为列结束为止</param>
         /// <param name="valueList">单元格合并后值的集合，与合并单元格索引数组集合一一对应</param>
         //public void SetCellRangeAddress(ISheet sheet, int rowstart, int rowend, int colstart, int colend, string value)
         public void SetExcelHeader(ISheet sheet, IList<int[]> mergeArrayList, IList<string> valueList)
         {
             for (int m = ; m < mergeArrayList.Count; m++)
             {
                 if (mergeArrayList[m].Length > )
                 {
                     return;
                 }
                 int rowstart = mergeArrayList[m][];
                 int rowend = mergeArrayList[m][];
                 int colstart = mergeArrayList[m][];
                 int colend = mergeArrayList[m][];
                 string value = "";
                 if (m < valueList.Count)
                 {
                     value = valueList[m];
                 }
                 ICellStyle style = workbook.CreateCellStyle();
                 style.Alignment = HorizontalAlignment.Center;
                 IFont font = workbook.CreateFont();
                 font.Boldweight = ;
                 font.FontHeight =  * ;
                 style.SetFont(font);
                 for (int i = rowstart; i < rowend + ; i++)
                 {
                     IRow row = sheet.GetRow(i);
                     if (row==null)
                     {
                         row = sheet.CreateRow(i);
                     }
                     for (int j = colstart; j < colend + ; j++)
                     {
                         ICell cell = row.CreateCell(j);
                         cell.SetCellValue(value);
                         cell.CellStyle = style;
                     }
                 }
                 if (rowend - rowstart >  || colend - colstart > )
                 {
                     CellRangeAddress cellRangeAddress = new CellRangeAddress(rowstart, rowend, colstart, colend);
                     sheet.AddMergedRegion(cellRangeAddress);
                 }
             }
             //workbook.Write(fs);
         }

         public void Dispose()
         {
             Dispose(true);
             GC.SuppressFinalize(this);
         }

         protected virtual void Dispose(bool disposing)
         {
             if (!this.disposed)
             {
                 if (disposing)
                 {
                     if (fs != null)
                         fs.Close();
                 }

                 fs = null;
                 disposed = true;
             }
         }
     }
 }

CommenClass