在C#中使用NPOI2.0操作Excel2003和Excel2007
Excel2003：
#region Excel2003 /// <summary> /// 将Excel文件中的数据读出到DataTable中(xls) /// </summary> /// <param name="file"></param> /// <returns></returns> public static DataTable ExcelToTableForXLS(string file) { DataTable dt = new DataTable(); using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read)) { XLS.HSSFWorkbook hssfworkbook = new XLS.HSSFWorkbook(fs); ISheet sheet = hssfworkbook.GetSheetAt(0); //表头 IRow header = sheet.GetRow(sheet.FirstRowNum); List<int> columns = new List<int>(); for (int i = 0; i < header.LastCellNum; i++) { object obj = GetValueTypeForXLS(header.GetCell(i) as XLS.HSSFCell); if (obj == null || obj.ToString() == string.Empty) { dt.Columns.Add(new DataColumn("Columns" + i.ToString())); //continue; } else dt.Columns.Add(new DataColumn(obj.ToString())); columns.Add(i); } //数据 for (int i = sheet.FirstRowNum + 1; i <= sheet.LastRowNum; i++) { DataRow dr = dt.NewRow(); bool hasValue = false; foreach (int j in columns) { dr[j] = GetValueTypeForXLS(sheet.GetRow(i).GetCell(j) as XLS.HSSFCell); if (dr[j] != null && dr[j].ToString() != string.Empty) { hasValue = true; } } if (hasValue) { dt.Rows.Add(dr); } } } return dt; } /// <summary> /// 将DataTable数据导出到Excel文件中(xls) /// </summary> /// <param name="dt"></param> /// <param name="file"></param> public static void TableToExcelForXLS(DataTable dt, string file) { XLS.HSSFWorkbook hssfworkbook = new XLS.HSSFWorkbook(); ISheet sheet = hssfworkbook.CreateSheet("Test"); //表头 IRow row = sheet.CreateRow(0); for (int i = 0; i < dt.Columns.Count; i++) { ICell cell = row.CreateCell(i); cell.SetCellValue(dt.Columns[i].ColumnName); } //数据 for (int i = 0; i < dt.Rows.Count; i++) { IRow row1 = sheet.CreateRow(i + 1); for (int j = 0; j < dt.Columns.Count; j++) { ICell cell = row1.CreateCell(j); cell.SetCellValue(dt.Rows[i][j].ToString()); } } //转为字节数组 MemoryStream stream = new MemoryStream(); hssfworkbook.Write(stream); var buf = stream.ToArray(); //保存为Excel文件 using (FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write)) { fs.Write(buf, 0, buf.Length); fs.Flush(); } } /// <summary> /// 获取单元格类型(xls) /// </summary> /// <param name="cell"></param> /// <returns></returns> private static object GetValueTypeForXLS(XLS.HSSFCell cell) { if (cell == null) return null; switch (cell.CellType) { case CellType.BLANK: //BLANK: return null; case CellType.BOOLEAN: //BOOLEAN: return cell.BooleanCellValue; case CellType.NUMERIC: //NUMERIC: return cell.NumericCellValue; case CellType.STRING: //STRING: return cell.StringCellValue; case CellType.ERROR: //ERROR: return cell.ErrorCellValue; case CellType.FORMULA: //FORMULA: default: return "=" + cell.CellFormula; } } #endregion
Excel2007：
#region Excel2007 /// <summary> /// 将Excel文件中的数据读出到DataTable中(xlsx) /// </summary> /// <param name="file"></param> /// <returns></returns> public static DataTable ExcelToTableForXLSX(string file) { DataTable dt = new DataTable(); using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read)) { XSSFWorkbook xssfworkbook = new XSSFWorkbook(fs); ISheet sheet = xssfworkbook.GetSheetAt(0); //表头 IRow header = sheet.GetRow(sheet.FirstRowNum); List<int> columns = new List<int>(); for (int i = 0; i < header.LastCellNum; i++) { object obj = GetValueTypeForXLSX(header.GetCell(i) as XSSFCell); if (obj == null || obj.ToString() == string.Empty) { dt.Columns.Add(new DataColumn("Columns" + i.ToString())); //continue; } else dt.Columns.Add(new DataColumn(obj.ToString())); columns.Add(i); } //数据 for (int i = sheet.FirstRowNum + 1; i <= sheet.LastRowNum; i++) { DataRow dr = dt.NewRow(); bool hasValue = false; foreach (int j in columns) { dr[j] = GetValueTypeForXLSX(sheet.GetRow(i).GetCell(j) as XSSFCell); if (dr[j] != null && dr[j].ToString() != string.Empty) { hasValue = true; } } if (hasValue) { dt.Rows.Add(dr); } } } return dt; } /// <summary> /// 将DataTable数据导出到Excel文件中(xlsx) /// </summary> /// <param name="dt"></param> /// <param name="file"></param> public static void TableToExcelForXLSX(DataTable dt, string file) { XSSFWorkbook xssfworkbook = new XSSFWorkbook(); ISheet sheet = xssfworkbook.CreateSheet("Test"); //表头 IRow row = sheet.CreateRow(0); for (int i = 0; i < dt.Columns.Count; i++) { ICell cell = row.CreateCell(i); cell.SetCellValue(dt.Columns[i].ColumnName); } //数据 for (int i = 0; i < dt.Rows.Count; i++) { IRow row1 = sheet.CreateRow(i + 1); for (int j = 0; j < dt.Columns.Count; j++) { ICell cell = row1.CreateCell(j); cell.SetCellValue(dt.Rows[i][j].ToString()); } } //转为字节数组 MemoryStream stream = new MemoryStream(); xssfworkbook.Write(stream); var buf = stream.ToArray(); //保存为Excel文件 using (FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write)) { fs.Write(buf, 0, buf.Length); fs.Flush(); } } /// <summary> /// 获取单元格类型(xlsx) /// </summary> /// <param name="cell"></param> /// <returns></returns> private static object GetValueTypeForXLSX(XSSFCell cell) { if (cell == null) return null; switch (cell.CellType) { case CellType.BLANK: //BLANK: return null; case CellType.BOOLEAN: //BOOLEAN: return cell.BooleanCellValue; case CellType.NUMERIC: //NUMERIC: return cell.NumericCellValue; case CellType.STRING: //STRING: return cell.StringCellValue; case CellType.ERROR: //ERROR: return cell.ErrorCellValue; case CellType.FORMULA: //FORMULA: default: return "=" + cell.CellFormula; } }
注意：操作Excel2003与操作Excel2007使用的是不同的命名空间下的内容
使用NPOI.HSSF.UserModel空间下的HSSFWorkbook操作Excel2003
使用NPOI.XSSF.UserModel空间下的XSSFWorkbook操作Excel2007
/// <summary> /// 写入到文件 IWorkbook 接口实现 /// </summary> /// <param name="book"></param> /// <param name="fileName"></param> /// <returns></returns> private bool WriteToFile(IWorkbook book, string fileName) { bool result = true; try { using (MemoryStream ms = new MemoryStream()) { string filePath = Path.GetDirectoryName(fileName); if (!Directory.Exists(filePath)) { Directory.CreateDirectory(filePath); } book.Write(ms); //保存为Excel文件 var buf = ms.ToArray(); using (FileStream fs = new FileStream(fileName, FileMode.Create, FileAccess.Write)) { fs.Write(buf, 0, buf.Length); fs.Flush(); } } } catch (Exception e) { LogHelper.WriteErrorLog(e.Message, e); result = false; } finally { GC.Collect(); } return result; }
