<span style="font-size:24px;"><span style="font-size:24px;"><span style="font-size:24px;">public class ExcelOperateInterface{//获取excel操作类对象public static ExcelOperateInterface CreateInterfaceInstance(){ExcelOperateInterface eoi = null;//switch (EnvirMemory.excelOperateTool)//{//    case ExcelOperateToolType.Excel_Office://        {//            eoi = new ExcelOffice();//        } break;//    case ExcelOperateToolType.Excel_NPOI://        {eoi = new ExcelNPOI();//    } break;//case ExcelOperateToolType.Excel_Defalut://    {//        eoi = new ExcelOffice();//    } break;//default://    {//        eoi = new ExcelOffice();//    } break;//}return eoi;}public virtual void OpenFile(string file,int iSheetIndex) { }public virtual void CreateFile(string file, int iSheetIndex) { }public virtual void CloseFile(bool bsave) { }public virtual string GetCellValue(int iRowIndex, int iColumnIndex) { return ""; }public virtual void SetCellValue(string sValue, int iRowIndex, int iColumnIndex) { }public virtual string GetDateCellValue(int iRowIndex, int iColumnIndex) { return ""; }}
</span></span></span>

接下来是具体的实现类：

<span style="font-size:24px;"><span style="font-size:24px;">public class ExcelNPOI : ExcelOperateInterface{private string filename;private IWorkbook m_iWorkbook;private ISheet m_iSheet;private void iInitEnvironment(){filename = "";m_iWorkbook = null;m_iSheet = null;}private void SaveFile(){try{//NPOI保存文件时，最好是先删除以前的 再新建一个文件//FilesManager.DeleteFile(filename);//新建文件流using (FileStream stream = new FileStream(filename, FileMode.OpenOrCreate, FileAccess.Write)){int i = m_iWorkbook.NumberOfSheets;for (int ii = 0; ii < i; ++ii){ISheet ish = m_iWorkbook.GetSheetAt(ii);ish.DisplayGridlines = true;ish.DisplayRowColHeadings = true;}m_iWorkbook.Write(stream);stream.Flush();}}catch (Exception ex){}}public override void CreateFile(string file,int iSheetIndex){try{IWorkbook workbook = new XSSFWorkbook();ISheet sheet = workbook.CreateSheet("sheet0");for (int i = 0; i < 450; i++){IRow row = sheet.CreateRow(i);for (int j = 0; j < 50; j++){ICell cell = row.CreateCell(j);cell.SetCellValue("lcy");}}using (FileStream fs = File.OpenWrite(file)){workbook.Write(fs);}}catch (Exception ex){throw;}}public override void OpenFile(string file, int iSheetIndex){try{iInitEnvironment();filename = file;using (FileStream sfile = new FileStream(file, FileMode.Open, FileAccess.Read)){m_iWorkbook = WorkbookFactory.Create(sfile);if (m_iWorkbook != null){m_iSheet = m_iWorkbook.GetSheetAt(iSheetIndex - 1);}}}catch (Exception ex){}}public override void CloseFile(bool bsave){try{if (bsave){SaveFile();}iInitEnvironment();}catch{}}public override string GetCellValue(int iRowIndex, int iColumnIndex){string sResult = "";try{IRow irow = m_iSheet.GetRow(iRowIndex - 1);if (irow != null){ICell icell = irow.GetCell(iColumnIndex - 1);if (icell != null){sResult = icell.ToString();}}}catch{}return sResult;}public override string GetDateCellValue(int iRowIndex, int iColumnIndex){string sResult = "";try{IRow irow = m_iSheet.GetRow(iRowIndex - 1);if (irow != null){ICell icell = irow.GetCell(iColumnIndex - 1);if (icell != null){DateTime dt;if (DateTime.TryParse(icell.ToString(), out dt)){if (icell.CellType == CellType.Numeric){sResult = icell.DateCellValue.ToString();}else{sResult = icell.ToString();}}}}}catch{}return sResult;}public override void SetCellValue(string sValue, int iRowIndex, int iColumnIndex){try{//CreateFile("D:\\excel333.xls", 1);IRow irow = m_iSheet.GetRow(iRowIndex - 1);if (irow == null){irow = m_iSheet.CreateRow(iRowIndex - 1);}ICell icell = irow.GetCell(iColumnIndex - 1);if (icell == null){icell = irow.CreateCell(iColumnIndex - 1);}icell.SetCellType(CellType.String);if (sValue == ""){sValue = "/";}icell.SetCellValue(sValue);CloseFile(true);}catch{}}}</span></span>

最后就是调用了：方法很简单，我现在只用到了导出的功能，所以只用一个Create方法就可以实现了，打开、保存之类的方法是不需要的：

<span style="font-size:24px;"><span style="font-size:24px;"> string file = @"D:\\excel550.xls";ExcelOperate.ExcelOperateInterface.CreateInterfaceInstance().CreateFile(file, 1);</span></span>

另外，在项目中需要引用一下NPOI的dll文件，在网上比较好找，而且版本更新挺快的，所以在此就不再提供了。