NPOI新建和读取EXCEL

        //基本NPOI 1.2.5.0
        static void Main(string[] args)
        {
            string path = string.Format("E:\export{0}.xls", DateTime.Now.ToString("yyyyMMddhhmmss"));

            WriteAExcel(path);
            ReadAExcel(path);
            Console.ReadKey();
        }

        /// <summary>
        /// 创建测试
        /// </summary>
        /// <param name="path">路径</param>
        static void WriteAExcel(string path)
        {
            //创建工作薄
            HSSFWorkbook workbook = new HSSFWorkbook();
            //创建一个名称为"排班表"的表
            ISheet sheet = workbook.CreateSheet("排班表");

            int rowCount = 0;
            int colCount = 6;

            //创建一行, 此行为标题行
            IRow title = sheet.CreateRow(rowCount);
            title.CreateCell(0).SetCellValue(string.Format("{0}({1})", "消化内科", "珠海市人民医院"));

            //合并单元格
            CellRangeAddress cellRangeAddress = new CellRangeAddress(rowCount, rowCount, 0, colCount - 1);
            sheet.AddMergedRegion(cellRangeAddress);
            rowCount++;

            //创建一行, 空行
            sheet.CreateRow(rowCount);
            rowCount++;

            //创建一行，此行为第二行
            IRow headerRow = sheet.CreateRow(rowCount);
            rowCount++;

            //固定区域, 用于header
            sheet.CreateFreezePane(0, 1);

            string[] headerArray = new[] { "医生", "日期", "时间", "预约数", "挂号费", "状态" };

            //表头行
            for (int i = 0; i < headerArray.Length; i++)
            {
                headerRow.CreateCell(i).SetCellValue(headerArray[i]);
            }

            List<MyDataItem> dataList = new List<MyDataItem>();
            #region 测试数据
            dataList.Add(new MyDataItem() { ID = 1, DoctorName = "张某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 2, DoctorName = "李某", Date = DateTime.Now, Time = "下午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 3, DoctorName = "赵某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 4, DoctorName = "杨某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "停诊" });
            dataList.Add(new MyDataItem() { ID = 5, DoctorName = "黎某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 6, DoctorName = "张某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 7, DoctorName = "李某", Date = DateTime.Now, Time = "下午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 8, DoctorName = "赵某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 9, DoctorName = "杨某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "停诊" });
            dataList.Add(new MyDataItem() { ID = 10, DoctorName = "黎某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 11, DoctorName = "张某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 12, DoctorName = "李某", Date = DateTime.Now, Time = "下午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 13, DoctorName = "赵某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 14, DoctorName = "杨某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "停诊" });
            dataList.Add(new MyDataItem() { ID = 15, DoctorName = "黎某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 16, DoctorName = "张某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 17, DoctorName = "李某", Date = DateTime.Now, Time = "下午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 18, DoctorName = "赵某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            dataList.Add(new MyDataItem() { ID = 19, DoctorName = "杨某", Date = DateTime.Now, Time = "上午", Place = 3, Fee = 10, Status = "停诊" });
            dataList.Add(new MyDataItem() { ID = 20, DoctorName = "黎某", Date = DateTime.Now, Time = "中午", Place = 3, Fee = 10, Status = "排班" });
            #endregion

            //添加下拉选项(序列)
            AddDropdownList1(sheet, rowCount);

            //添加下拉选项(指定数据)
            AddDropdownList2(workbook, sheet, rowCount);

            //插入数据
            for (int i = 0; i < dataList.Count; i++)
            {
                MyDataItem item = dataList[i];
                IRow dataRow = sheet.CreateRow(rowCount);

                dataRow.CreateCell(0).SetCellValue(string.Format("{0}({1})", item.DoctorName, item.ID));
                dataRow.CreateCell(1).SetCellValue(item.Date.ToString("yyyy/MM/dd"));
                dataRow.CreateCell(2).SetCellValue(item.Time);
                dataRow.CreateCell(3).SetCellValue(item.Place);
                dataRow.CreateCell(4).SetCellValue(item.Fee.ToString("N2"));
                dataRow.CreateCell(5);//.SetCellValue(item.Status);
                rowCount++;
            }

            //写入文件
            using (MemoryStream ms = new MemoryStream())
            {
                workbook.Write(ms);

                using (FileStream fs = new FileStream(path, FileMode.Create))
                {
                    byte[] data = ms.ToArray();
                    fs.Write(data, 0, data.Count());
                }
            }
        }

        //读测试
        static void ReadAExcel(string path)
        {
            using (FileStream file = new FileStream(path, FileMode.Open, FileAccess.Read))
            {
                IWorkbook workbook = new HSSFWorkbook(file);
                ISheet sheet = workbook.GetSheet("排班表");
                IRow headerRow = sheet.GetRow(2);

                //一行最后一个方格的编号 即总的列数
                int cellCount = headerRow.LastCellNum;

                //有多少列
                int rowCount = sheet.LastRowNum;

                //读
                for (int i = 2; i < rowCount; i++)
                {
                    IRow row = sheet.GetRow(i);
                    for (int j = row.FirstCellNum; j < cellCount; j++)
                    {
                        Console.Write(" " + row.GetCell(j).ToString());
                    }
                    Console.WriteLine();
                }
            }
        }

        /// <summary>
        /// 添加下拉框(序列)
        /// </summary>
        /// <param name="sheet"></param>
        /// <param name="start"></param>
        static void AddDropdownList1(ISheet sheet, int start)
        {
            CellRangeAddressList regions = new CellRangeAddressList(start, 65535, 5, 5);
            DVConstraint constraint = DVConstraint.CreateExplicitListConstraint(new string[] { "就诊", "停诊" });
            HSSFDataValidation dataValidate = new HSSFDataValidation(regions, constraint);
            sheet.AddValidationData(dataValidate);
        }

        /// <summary>
        /// 添加下拉框(单元格)
        /// </summary>
        /// <param name="workbook"></param>
        /// <param name="sheet"></param>
        /// <param name="start"></param>
        static void AddDropdownList2(HSSFWorkbook workbook, ISheet sheet, int start)
        {
            ISheet sheet2 = workbook.CreateSheet("a");
            sheet2.CreateRow(0).CreateCell(0).SetCellValue("上午");
            sheet2.CreateRow(1).CreateCell(0).SetCellValue("中午");
            sheet2.CreateRow(2).CreateCell(0).SetCellValue("下午");
            sheet2.CreateRow(3).CreateCell(0).SetCellValue("晚上");

            IName range = workbook.CreateName();
            range.RefersToFormula = "a!$A$1:$A$4";
            range.NameName = "timeDic";

            CellRangeAddressList regions = new CellRangeAddressList(start, 65535, 2, 2);
            DVConstraint constraint = DVConstraint.CreateFormulaListConstraint("timeDic");
            HSSFDataValidation dataValidate = new HSSFDataValidation(regions, constraint);
            //添加约束警告
            dataValidate.CreateErrorBox("输入不合法", "请输入下拉列表中的值。");
            sheet.AddValidationData(dataValidate);
        }

        /// <summary>
        /// 测试数据类型
        /// </summary>
        class MyDataItem
        {
            public int ID { get; set; }

            public string DoctorName { get; set; }

            public DateTime Date { get; set; }

            public string Time { get; set; }

            public int Place { get; set; }

            public decimal Fee { get; set; }

            public string Status { get; set; }
        }

 备忘:

//2014/10/08

//加粗,15字
IFont Bold15Font = workbook.CreateFont();
Bold15Font.Boldweight = (short)FontBoldWeight.BOLD;
Bold15Font.FontHeightInPoints = 15;

//黄色底,横向居中,纵向居中,加粗,11字, 边框(单个)
ICellStyle YellowCenterBold11Cell = workbook.CreateCellStyle();
YellowCenterBold11Cell.FillForegroundColor = NPOI.HSSF.Util.HSSFColor.YELLOW.index;
YellowCenterBold11Cell.FillPattern = FillPatternType.SOLID_FOREGROUND;
YellowCenterBold11Cell.Alignment = HorizontalAlignment.CENTER;
YellowCenterBold11Cell.VerticalAlignment = VerticalAlignment.CENTER;
YellowCenterBold11Cell.SetFont(Bold11Font);
YellowCenterBold11Cell.BorderBottom = BorderStyle.THIN;
YellowCenterBold11Cell.BorderLeft = BorderStyle.THIN;
YellowCenterBold11Cell.BorderRight = BorderStyle.THIN;
YellowCenterBold11Cell.BorderTop = BorderStyle.THIN;

//给合并单元格加边框
CellRangeAddress cellRangeAddress0 = new CellRangeAddress(0, 0, 0, 3);
sheet.AddMergedRegion(cellRangeAddress0);
 ((HSSFSheet)sheet).SetEnclosedBorderOfRegion(cellRangeAddress0, BorderStyle.THIN, NPOI.HSSF.Util.HSSFColor.BLACK.index);

//单元格宽
sheet.SetColumnWidth(0, 10 * 256);

//行高
row0.HeightInPoints = Height25;

//2014/10/09
ISheet sheet1 = hssfworkbook.CreateSheet("Sheet1");
IRow row1 = sheet1.CreateRow(0);
ICell cel1 = row1.CreateCell(0);
ICell cel2 = row1.CreateCell(1);
ICellStyle unlocked = hssfworkbook.CreateCellStyle();
unlocked.IsLocked = false;
ICellStyle locked = hssfworkbook.CreateCellStyle();
locked.IsLocked = true;//确定当前单元格被设置保护
cel1.SetCellValue("没被锁定");
cel1.CellStyle = unlocked;
cel2.SetCellValue("被锁定");
cel2.CellStyle = locked;
sheet1.ProtectSheet("password");//设置密码保护
sheet1.AutoSizeColumn(i);//自动宽度(不支持中文)

自动宽度( 支持中文)

　　　　 /// <summary>
        /// 自动宽度支持中文
        /// </summary>
        public static void AutoSizeColumnExtension(this ISheet sheet, int maxColumn)
        {

            for (int i = 0; i < maxColumn; i++)
            {
                sheet.AutoSizeColumn(i);
            }

            //获取当前列的宽度，然后对比本列的长度，取最大值  
            for (int columnNum = 0; columnNum < maxColumn; columnNum++)
            {
                int columnWidth = sheet.GetColumnWidth(columnNum) / 256;
                for (int rowNum = 1; rowNum <= sheet.LastRowNum; rowNum++)
                {
                    IRow currentRow;
                    //当前行未被使用过  
                    if (sheet.GetRow(rowNum) == null)
                    {
                        currentRow = sheet.CreateRow(rowNum);
                    }
                    else
                    {
                        currentRow = sheet.GetRow(rowNum);
                    }

                    if (currentRow.GetCell(columnNum) != null)
                    {
                        ICell currentCell = currentRow.GetCell(columnNum);
                        int length = Encoding.Default.GetBytes(currentCell.ToString()).Length;
                        if (columnWidth < length)
                        {
                            columnWidth = length;
                        }
                    }
                }
                sheet.SetColumnWidth(columnNum, (columnWidth > 255 ? 255 : columnWidth) * 256);
            }
        }

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