NOPI导出execl 多个sheet,一列图片

NPOI API: http://www.cnblogs.com/atao/archive/2009/11/15/1603528.html

http://blog.csdn.net/pan_junbiao/article/details/39717443 -- NPOI使用手册

http://www.cnblogs.com/wei325/p/4748324.html 

每一张表只能有一个HSSFPatriarch对象，如果把它的创建放到了setPic方法中，那么一行只会出现一张图片，最后的图片会消掉之前的图片。也不能放到for循环里

HSSFClientAnchor(dx1,dy1,dx2,dy2,col1,row1,col2,row2)的参数，有必要在这里说明一下：
dx1：起始单元格的x偏移量，如例子中的255表示直线起始位置距A1单元格左侧的距离；
dy1：起始单元格的y偏移量，如例子中的125表示直线起始位置距A1单元格上侧的距离；
dx2：终止单元格的x偏移量，如例子中的1023表示直线起始位置距C3单元格左侧的距离；
dy2：终止单元格的y偏移量，如例子中的150表示直线起始位置距C3单元格上侧的距离；
col1：起始单元格列序号，从0开始计算；
row1：起始单元格行序号，从0开始计算，如例子中col1=0,row1=0就表示起始单元格为A1；
col2：终止单元格列序号，从0开始计算；
row2：终止单元格行序号，从0开始计算，如例子中col2=2,row2=2就表示起始单元格为C3；

//添加多个图片时:多个pic应该share同一个DrawingPatriarch在同一个sheet里面。

        //获取枚举类型的Display特性的name值
        public string GetEnumTxt(Enum eEnum)
        {
            var enumType = eEnum.GetType();
            var field = enumType.GetField(eEnum.ToString());
            var display = field.GetCustomAttributes(typeof(DisplayAttribute), false).FirstOrDefault() as DisplayAttribute;
            return display != null ? display.Name : eEnum.ToString();
        }

        private void setPic(HSSFWorkbook workbook, HSSFPatriarch patriarch,string path, ISheet sheet, int rowline, int col)
        {
            if(string.IsNullOrEmpty(path))return;
            byte[] bytes = System.IO.File.ReadAllBytes(Server.MapPath(path));
            int pictureIdx = workbook.AddPicture(bytes, PictureType.JPEG);
            // 插图片的位置  HSSFClientAnchor（dx1,dy1,dx2,dy2,col1,row1,col2,row2) 后面再作解释
            HSSFClientAnchor anchor = new HSSFClientAnchor(70, 10, 0, 0, col, rowline, col+1, rowline + 1);
            //把图片插到相应的位置
            HSSFPicture pict = (HSSFPicture)patriarch.CreatePicture(anchor, pictureIdx);
        }

private void setPic(HSSFWorkbook workbook, HSSFPatriarch patriarch,string path, ISheet sheet, int rowline, int col)
        {
            if(string.IsNullOrEmpty(path))return;
            byte[] bytes = System.IO.File.ReadAllBytes(Server.MapPath(path));
            int pictureIdx = workbook.AddPicture(bytes, PictureType.JPEG);
            // 插图片的位置  HSSFClientAnchor（dx1,dy1,dx2,dy2,col1,row1,col2,row2) 后面再作解释
            HSSFClientAnchor anchor = new HSSFClientAnchor(70, 10, 0, 0, col, rowline, col+1, rowline + 1);
            //把图片插到相应的位置
            HSSFPicture pict = (HSSFPicture)patriarch.CreatePicture(anchor, pictureIdx);
        }

导出多个sheet,一列图片

        /// <summary>
        /// 导出EXCEL,可以导出多个sheet(图片)
        /// </summary>
        /// <param name="dtSources">sheet数据源</param>
        /// <param name="lstColname">sheet列名数据</param>
        /// <param name="sheetname">sheet名</param>
        /// <param name="filename">文件名</param>
        /// <param name="mColImage">图像列</param>
        /// <returns></returns>
        public static string ExporMultiSheetImage(List<DataTable> dtSources, List<List<string>> lstColname, List<string> sheetname, string filename,int mColImage)
        {
            //创建工作薄  
            IWorkbook workbook = new HSSFWorkbook();
            string FileName = filename + ".xls";
            for (int k = 0; k < dtSources.Count; k++)
            {
                //DataTable dt = dtSources[k];
                int iSheetCount = Convert.ToInt32(Math.Ceiling(Convert.ToDouble(dtSources[k].Rows.Count) / 10000));
                iSheetCount = iSheetCount == 0 ? 1 : iSheetCount;

                for (int iSheetIndex = 0; iSheetIndex < iSheetCount; iSheetIndex++)
                {
                    #region 图最大列

                    int mImageColMerage = 0;    //  图最大列
                    Dictionary<int, List<string>> dicImagePath = new Dictionary<int, List<string>>();

                    if (mColImage > -1)
                    {
                        List<int> lstImageColLen = new List<int>();

                        for (int i = iSheetIndex * 10000; i < dtSources[k].Rows.Count; i++)
                        {
                            List<string> lstImagePath = dtSources[k].Rows[i][mColImage].ToString().Trim(',').Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries).ToList();
                            dicImagePath[i] = lstImagePath;
                            lstImageColLen.Add(lstImagePath.Count());
                        }
                        mImageColMerage = lstImageColLen.Max();
                    }

                    #endregion

                    //create sheet 
                    string sheetName = string.Empty; 
                    if (iSheetCount>1)
                    {
                        sheetName = sheetname[k] + iSheetIndex;
                    }
                    else
                    {
                        sheetName = sheetname[k];
                    }
                    ISheet sheet = workbook.CreateSheet(sheetName);
                    sheet.PrintSetup.Landscape = true;     //是否横向排版
                    sheet.FitToPage = false;               //是否自适应页面
                    sheet.PrintSetup.Scale = 50;           //缩放比例

                    //填充列标题以及样式  
                    int rowsNum = 0;  //行号  
                    IRow headerRow = sheet.CreateRow(rowsNum);
                    ICellStyle headStyle = workbook.CreateCellStyle();
                    headStyle.Alignment = HorizontalAlignment.CENTER;
                    headerRow.HeightInPoints = 20;
                    headStyle.VerticalAlignment = VerticalAlignment.CENTER;
                    //换行
                    //headStyle.WrapText = true;

                    IFont font = workbook.CreateFont();
                    font.FontHeightInPoints = 13;
                    font.Boldweight = 700;
                    headStyle.SetFont(font);

                    for (int i = 0; i < lstColname[k].Count; i++)
                    {
                        if (i < mColImage)
                        {
                            //合并列前
                            headerRow.CreateCell(i, CellType.STRING).SetCellValue(lstColname[k][i]);
                            headerRow.GetCell(i).CellStyle = headStyle;
                        }
                        else if (mColImage > -1 && i == mColImage)
                        {
                            headerRow.CreateCell(i, CellType.STRING).SetCellValue(lstColname[k][i]);
                            headerRow.GetCell(i).CellStyle = headStyle;
                            sheet.AddMergedRegion(new CellRangeAddress(0, 0, mColImage, mColImage + mImageColMerage));
                        }
                        else
                        {
                            //合并列后
                            headerRow.CreateCell(i + mImageColMerage, CellType.STRING).SetCellValue(lstColname[k][i]);
                            headerRow.GetCell(i + mImageColMerage).CellStyle = headStyle;
                        }
                        //sheet.AutoSizeColumn(i);
                        sheet.SetColumnWidth(i, 5000);  //列宽
                        //headerRow.Cells[i].SetCellValue(new HSSFRichTextString("
"));  //强制换行
                    }

                    ICellStyle cellStyle = workbook.CreateCellStyle();
                    cellStyle.Alignment = HorizontalAlignment.CENTER;
                    cellStyle.VerticalAlignment = VerticalAlignment.CENTER;
                    IFont cellfont = workbook.CreateFont();
                    cellfont.FontHeightInPoints = 10;
                    cellStyle.SetFont(cellfont);
                    cellStyle.WrapText = true;

                    #region MyRegion

                    //填充数据行  
                    IRow dataRow = null;
                    rowsNum = 1;  //行号，从第2行开始  
                    /// patriarch 画图的顶级管理器，一个sheet只能获取一个（一定要注意这点）
                    HSSFPatriarch patriarch = (HSSFPatriarch)sheet.CreateDrawingPatriarch();
                    //填充内容
                    for (int i = iSheetIndex * 10000; i < dtSources[k].Rows.Count; i++)
                    {
                        dataRow = sheet.CreateRow(i + 1);

                        for (int j = 0; j < dtSources[k].Columns.Count; j++)
                        {
                            //sheet.SetColumnWidth(j, 5000);
                            //sheet.AutoSizeColumn(j);
                            if (j < mColImage)
                            {
                                //合并列前
                                dataRow.CreateCell(j).SetCellValue(dtSources[k].Rows[i][j].ToString());
                                dataRow.GetCell(j).CellStyle = cellStyle;
                            }
                            else if (mColImage > -1 && j == mColImage)
                            {
                                int mImgIndex = 0;
                                foreach (var item in dicImagePath[i])
                                {
                                    string imgPath = HttpContext.Current.Server.MapPath(item);
                                    if (File.Exists(imgPath))
                                    {
                                        byte[] bytes = System.IO.File.ReadAllBytes(imgPath);
                                        int pictureIdx = workbook.AddPicture(bytes, PictureType.JPEG);
                                        ///// patriarch 画图的顶级管理器，一个sheet只能获取一个（一定要注意这点）
                                        //HSSFPatriarch patriarch = (HSSFPatriarch)sheet.CreateDrawingPatriarch();
                                        // 插图片的位置  HSSFClientAnchor（dx1,dy1,dx2,dy2,col1,row1,col2,row2) 
                                        //图片左上角为（col, row）第row+1行col+1列，右下角为（ col +1, row +1）第 col +1+1行row +1+1列，宽为100，高为50
                                        HSSFClientAnchor anchor = new HSSFClientAnchor(0, 0, 1000, 250, mColImage + mImgIndex, i + 1, mColImage + mImgIndex, i + 1);
                                        //把图片插到相应的位置
                                        HSSFPicture pict = (HSSFPicture)patriarch.CreatePicture(anchor, pictureIdx);
                                        //pict.Resize(0.7);   //用图片原始大小来显示
                                    }
                                    mImgIndex++;
                                }
                                dataRow.CreateCell(j).SetCellValue("");
                                dataRow.GetCell(j).CellStyle = cellStyle;
                                sheet.AddMergedRegion(new CellRangeAddress(i + 1, i + 1, mColImage, mColImage + mImageColMerage));
                            }
                            else 
                            {
                                //合并列后
                                dataRow.CreateCell(j + mImageColMerage).SetCellValue(dtSources[k].Rows[i][j].ToString());
                                dataRow.GetCell(j + mImageColMerage).CellStyle = cellStyle;
                            }

                        }
                    }

                    #endregion
                }
            }

            string strPhysicsPath = HttpContext.Current.Server.MapPath(Config.AccPath + "Temp/Export");

            if (!Directory.Exists(strPhysicsPath))
            {
                Directory.CreateDirectory(strPhysicsPath);
            }
            //string resultUrl = Config.LogPath.Replace("~", HttpContext.Current.Request.Url.Host + ":" + HttpContext.Current.Request.Url.Port) + "Temp/" + DateTime.Today.Year;
            string tempUrl = "/" + DateTime.Today.ToString("MMdd-") + Guid.NewGuid().ToString() + ".xls";
            strPhysicsPath = strPhysicsPath.TrimEnd('\') + tempUrl;
            //-------
            using (MemoryStream ms = new MemoryStream())
            {
                ms.Flush();
                ms.Position = 0;
                workbook.Write(ms);
                using (FileStream fs = new FileStream(strPhysicsPath, FileMode.Create, FileAccess.Write))
                {
                    byte[] fData = ms.ToArray();
                    fs.Write(fData, 0, fData.Length);
                    fs.Flush();
                }
                LogHelper.WriteExportLog(filename);
                return Config.AccPath.Replace("~", "") + "Temp/Export" + tempUrl;
            }

            #region  浏览器下载

            //供浏览器下载Excel  
            //if (HttpContext.Current.Request.Browser.Browser == "IE")
            //    FileName = HttpUtility.UrlEncode(FileName);
            //using (MemoryStream ms = new MemoryStream())
            //{
            //    ms.Position = 0;
            //    workbook.Write(ms);
            //    ms.Flush();
            //    HttpContext curContext = HttpContext.Current;

            //    // 设置编码和附件格式  
            //    curContext.Response.ContentType = "application/vnd.ms-excel";
            //    curContext.Response.ContentEncoding = Encoding.UTF8;
            //    curContext.Response.Charset = "";
            //    curContext.Response.AppendHeader("Content-Disposition",
            //         "attachment;filename=" + HttpUtility.UrlEncode(FileName, Encoding.UTF8));
            //    curContext.Response.BinaryWrite(ms.GetBuffer());
            //    ms.Close();
            //    ms.Dispose();
            //    curContext.Response.End();
            //}
            #endregion
        }

 导出EXCEL,可以导出多个sheet

        /// <summary>
        /// 导出EXCEL,可以导出多个sheet
        /// </summary>
        /// <param name="dtSources">原始数据数组类型</param>
        /// <param name="strFileName">路径</param>
        public static string ExporMultiSheet(DataTable[] dtSources, List<List<string>> lstname, List<string> sheetname, string filename)
        {
            //创建工作薄  
            IWorkbook workbook = new HSSFWorkbook();

            string FileName = filename + ".xls";

            for (int k = 0; k < dtSources.Length; k++)
            {
                ISheet sheet = workbook.CreateSheet(sheetname[k]);
                //设置列宽
                sheet.SetColumnWidth(0, 30 * 256);
                sheet.SetColumnWidth(1, 30 * 256);
                sheet.SetColumnWidth(2, 20 * 256);
                sheet.SetColumnWidth(3, 20 * 256);
                sheet.SetColumnWidth(4, 20 * 256);
                sheet.SetColumnWidth(5, 25 * 256);
                //填充表头
                //填充列标题以及样式  
                int rowsNum = 0;  //行号  
                IRow headerRow = sheet.CreateRow(rowsNum);
                ICellStyle headStyle = workbook.CreateCellStyle();
                headStyle.Alignment = HorizontalAlignment.CENTER;
                headStyle.VerticalAlignment = VerticalAlignment.CENTER;
                //换行
                headStyle.WrapText = true;

                headerRow.HeightInPoints = 20;
                IFont font = workbook.CreateFont();
                font.FontHeightInPoints = 13;
                font.Boldweight = 700;
                headStyle.SetFont(font);
                for (int i = 0; i < lstname[k].Count; i++)
                {
                    headerRow.CreateCell(i, CellType.STRING).SetCellValue(lstname[k][i]);
                    headerRow.GetCell(i).CellStyle = headStyle;
                    //headerRow.Cells[i].SetCellValue(new HSSFRichTextString("
"));  //强制换行
                }

                ICellStyle cellStyle = workbook.CreateCellStyle();
                cellStyle.Alignment = HorizontalAlignment.CENTER;
                cellStyle.VerticalAlignment = VerticalAlignment.CENTER;
                IFont cellfont = workbook.CreateFont();
                cellfont.FontHeightInPoints = 10;
                cellStyle.SetFont(cellfont);
                cellStyle.WrapText = true;

                //填充数据行  
                IRow dataRow = null;
                rowsNum = 1;  //行号，从第2行开始  

                //填充内容
                for (int i = 0; i < dtSources[k].Rows.Count; i++)
                {
                    dataRow = sheet.CreateRow(i + 1);

                    for (int j = 0; j < dtSources[k].Columns.Count; j++)
                    {
                        dataRow.CreateCell(j).SetCellValue(dtSources[k].Rows[i][j].ToString());
                        dataRow.GetCell(j).CellStyle = cellStyle;
                    }
                }
            }

            //保存
            string strPhysicsPath = HttpContext.Current.Server.MapPath(Config.AccPath + "Temp/Export");

            if (!Directory.Exists(strPhysicsPath))
            {
                Directory.CreateDirectory(strPhysicsPath);
            }
            string tempUrl = "/" + DateTime.Today.ToString("MMdd-") + Guid.NewGuid().ToString() + ".xls";
            strPhysicsPath = strPhysicsPath.TrimEnd('\') + tempUrl;

            using (MemoryStream ms = new MemoryStream())
            {
                ms.Flush();
                ms.Position = 0;
                workbook.Write(ms);
                using (FileStream fs = new FileStream(strPhysicsPath, FileMode.Create, FileAccess.Write))
                {
                    byte[] fData = ms.ToArray();
                    fs.Write(fData, 0, fData.Length);
                    fs.Flush();
                }
                LogHelper.WriteExportLog(filename);
                return Config.AccPath.Replace("~", "") + "Temp/Export" + tempUrl;
            }
        }

图片base64形式怎么转为图片

String u = "Base64";
            // Base64解码
            byte[] b = new BASE64Decoder().decodeBuffer(u);
            // 生成图片
            String imgName = "echartsPhoto";
            String filePath = ServletActionContext.getServletContext().getRealPath("/") + "echarts";
            String fileName = filePath +"/"+ imgName +".png";
                   
            File file = new File(filePath);
            if(!file.exists()){
                file.mkdir();
            }
            OutputStream out = new FileOutputStream(new File(fileName));
            out.write(b);18             out.close();

API 导出execl

public static string ExportExecl(DataTable dataSource,string filename)
        {
            //创建工作薄  
            IWorkbook workbook = new HSSFWorkbook();

            ISheet sheet = workbook.CreateSheet(filename);
            sheet.PrintSetup.Landscape = true;     //是否横向排版
            sheet.FitToPage = false;               //是否自适应页面
            sheet.PrintSetup.Scale = 50;           //缩放比例

            //填充列标题以及样式  
            int rowsNum = 0;  //行号  
            IRow headerRow = sheet.CreateRow(rowsNum);
            ICellStyle headStyle = workbook.CreateCellStyle();
            headStyle.Alignment = HorizontalAlignment.CENTER;
            headStyle.VerticalAlignment = VerticalAlignment.CENTER;
            headerRow.HeightInPoints = 20;

            IFont font = workbook.CreateFont();
            font.FontHeightInPoints = 13;
            font.Boldweight = 700;
            headStyle.SetFont(font);

            for (int i = 0; i < dataSource.Columns.Count; i++)
            {
                headerRow.CreateCell(i).SetCellValue(dataSource.Columns[i].ColumnName);
                headerRow.Cells[i].CellStyle = headStyle;
                //sheet.SetColumnWidth(i, 5000);
                sheet.AutoSizeColumn(i); 
            }

            //ICellStyle cellStyle = workbook.CreateCellStyle();
            //cellStyle.Alignment = HorizontalAlignment.CENTER;
            //cellStyle.VerticalAlignment = VerticalAlignment.CENTER;
            //IFont cellfont = workbook.CreateFont();
            //cellfont.FontHeightInPoints = 10;
            //cellStyle.SetFont(cellfont);
            //cellStyle.WrapText = true;

            for (int i = 1; i < dataSource.Rows.Count; i++)
            {
                IRow datarow = sheet.CreateRow(i);
                for (int j = 0; j < dataSource.Columns.Count; j++)
                {
                    datarow.CreateCell(j).SetCellValue(dataSource.Rows[i][j].ToString());
                    //datarow.Cells[j].CellStyle = cellStyle;
                }
            }
            using (MemoryStream ms = new MemoryStream())
            {
                workbook.Write(ms);
                ms.Flush();
                ms.Position = 0;

                //保存
                string strPhysicsPath = HttpContext.Current.Server.MapPath(Config.AccPath + "Temp/Export");

                if (!Directory.Exists(strPhysicsPath))
                {
                    Directory.CreateDirectory(strPhysicsPath);
                }
                string tempUrl = "/" + DateTime.Today.ToString("MMdd-") + Guid.NewGuid().ToString() + ".xls";
                strPhysicsPath = strPhysicsPath.TrimEnd('\') + tempUrl;
                using (FileStream fs = new FileStream(strPhysicsPath, FileMode.Create, FileAccess.Write))
                {
                    byte[] fData = ms.ToArray();
                    fs.Write(fData, 0, fData.Length);
                    fs.Flush();
                }
                LogHelper.WriteExportLog(filename);
                return Config.AccPath.Replace("~", "") + "Temp/Export" + tempUrl;

                //return ms; 
            }

            #region  浏览器下载

            //供浏览器下载Excel  
            //if (HttpContext.Current.Request.Browser.Browser == "IE")
            //    FileName = HttpUtility.UrlEncode(FileName);
            //using (MemoryStream ms = new MemoryStream())
            //{
            //    ms.Position = 0;
            //    workbook.Write(ms);
            //    ms.Flush();
            //    HttpContext curContext = HttpContext.Current;

            //    // 设置编码和附件格式  
            //    curContext.Response.ContentType = "application/vnd.ms-excel";
            //    curContext.Response.ContentEncoding = Encoding.UTF8;
            //    curContext.Response.Charset = "";
            //    curContext.Response.AppendHeader("Content-Disposition",
            //         "attachment;filename=" + HttpUtility.UrlEncode(FileName, Encoding.UTF8));
            //    curContext.Response.BinaryWrite(ms.GetBuffer());
            //    ms.Close();
            //    ms.Dispose();
            //    curContext.Response.End();
            //}
            #endregion
        }

EXECL第一行加标题 ，合并单元格

/// <summary>
        /// 导出EXECL
        /// </summary>
        /// <param name="data">数据源</param>
        /// <param name="colsname">列名</param>
        /// <param name="filename">文件名</param>
        /// <param name="filePath">文件路径</param>
        /// <param name="isTitle">是否包含标题</param>
        /// <returns>返回文件路径</returns>
        public static string ExportExcel(DataTable data, List<string> colsname, string filename,string filePath = null ,bool isTitle = false)
        {
            //创建工作薄  
            IWorkbook workbook = new HSSFWorkbook();    //else if (fileExt == ".xls") { workbook = new HSSFWorkbook(); }
            ISheet sheet = workbook.CreateSheet(filename);
            string FileName = filename + ".xls";

            //填充列标题以及样式  
            int headRowsNum = 0;  //行号  
            //是否有标题
            if (isTitle)
            {
                IRow headerTitleRow = sheet.CreateRow(headRowsNum);
                ICellStyle headTitleStyle = workbook.CreateCellStyle();
                headTitleStyle.Alignment = HorizontalAlignment.Center;
                headTitleStyle.VerticalAlignment = VerticalAlignment.Center;
                headerTitleRow.HeightInPoints = 20;

                IFont titlefont = workbook.CreateFont();
                titlefont.FontHeightInPoints = 13;
                titlefont.Boldweight = short.MaxValue;
                headTitleStyle.SetFont(titlefont);

                headerTitleRow.CreateCell(0, CellType.String).SetCellValue(filename);
                headerTitleRow.GetCell(0).CellStyle = headTitleStyle;
                //合并  CellRangeAddress四个参数为：起始行，结束行，起始列，结束列，合并后的内容与样式以该区域最左上角的单元格为准
                CellRangeAddress region = new CellRangeAddress(0, 0, 0, colsname.Count());
                sheet.AddMergedRegion(region);

                headRowsNum++;
            }

            IRow headerRow = sheet.CreateRow(headRowsNum);
            ICellStyle headStyle = workbook.CreateCellStyle();
            headStyle.Alignment = HorizontalAlignment.Center;
            headStyle.VerticalAlignment = VerticalAlignment.Center;
            headerRow.HeightInPoints = 20;

            IFont font = workbook.CreateFont();
            font.FontHeightInPoints = 13;
            font.Boldweight = 700;
            headStyle.SetFont(font);

            for (int i = 0; i < colsname.Count; i++)
            {
                headerRow.CreateCell(i, CellType.String).SetCellValue(colsname[i]);
                headerRow.GetCell(i).CellStyle = headStyle;
                //sheet.SetColumnWidth(i, 5000);  //列宽
                sheet.AutoSizeColumn(i);
            }

            ICellStyle cellStyle = workbook.CreateCellStyle();
            cellStyle.Alignment = HorizontalAlignment.Center;
            cellStyle.VerticalAlignment = VerticalAlignment.Center;
            IFont cellfont = workbook.CreateFont();
            cellfont.FontHeightInPoints = 10;
            cellStyle.SetFont(cellfont);
            //cellStyle.WrapText = true;

            //填充数据行  
            IRow row = null;
            int rowsNum = headRowsNum + 1;  //行号，从第2行开始 
            for (int i = 0; i < data.Rows.Count; i++)
            {
                //写入字段值  
                row = sheet.CreateRow(rowsNum);
                row.HeightInPoints = 18;
                for (int j = 0; j < colsname.Count; j++)
                {
                    row.CreateCell(j, CellType.String).SetCellValue(data.Rows[i][j].ToString());
                    row.GetCell(j).CellStyle = cellStyle;
                    //sheet.AutoSizeColumn(j);
                }

                rowsNum++;
            }

            //for (int i = 0; i < colsname.Count; i++)
            //{
            //    int columnWidth = sheet.GetColumnWidth(i) / 256;
            //    for (int j = 0; j < data.Rows.Count; j++)
            //    {
            //        ICell currentCell = sheet.GetRow(j).GetCell(i);
            //        int length = Encoding.Default.GetBytes(currentCell.ToString()).Length;
            //        if (columnWidth < length)
            //        {
            //            columnWidth = length;
            //        }
            //    }

            //    sheet.SetColumnWidth(i, (columnWidth + 1) * 256);
            //}

            string strPhysicsPath = string.Empty;
            if (!string.IsNullOrWhiteSpace(filePath))
            {
                strPhysicsPath = filePath;
            }
            else
            {
                strPhysicsPath = HttpContext.Current.Server.MapPath("~/" + "Temp/Export");
            }

            if (!Directory.Exists(strPhysicsPath))
            {
                Directory.CreateDirectory(strPhysicsPath);
            }
            string tempUrl = "/" + DateTime.Today.ToString("MMdd-") + filename + ".xls";
            strPhysicsPath = strPhysicsPath.TrimEnd('\') + tempUrl;

            using (MemoryStream ms = new MemoryStream())
            {
                ms.Flush();
                ms.Position = 0;
                workbook.Write(ms);
                using (FileStream fs = new FileStream(strPhysicsPath, FileMode.Create, FileAccess.Write))
                {
                    byte[] fData = ms.ToArray();
                    fs.Write(fData, 0, fData.Length);
                    fs.Flush();
                }
                //LogHelper.WriteExportLog(filename);
                //return Config.AccPath.Replace("~", "") + "Temp/Export" + tempUrl;

                LogHelper.Info(filename);
                return strPhysicsPath;
            }
        }

 //从第二行开始循环，和上一行进行判断，如果相同，则合并
        for (int i = 1; i < dt.Rows.Count; i++)
        {
            row = sheet.CreateRow(i + 1);
            for (int j = 0; j < dt.Columns.Count; j++)
            {
                string cellText = dt.Rows[i][j].ToString();
                row.CreateCell(j).SetCellValue(cellText);
                string temp = dt.Rows[i - 1][j].ToString();
                //temp上一行数据，一定要判断是否为空！！！j< dt.Columns.Count-7，不需要合并的列，也可以改成 && (j!=5 || j!=7)
                if (!string.IsNullOrEmpty(temp) && cellText== temp && j< dt.Columns.Count-7)
                {
                    //本行和上一行合并,为什么是 i和i+1，这里是从第几行开始合并，到第几行结束，i是在dt里的行数，而在表里，因为有表头，所以必须要加1
                    CellRangeAddress region = new CellRangeAddress(i, i+1, j, j);
                    sheet.AddMergedRegion(region);
                }
            }
        }
        style.Alignment = HorizontalAlignment.Center;
        style.VerticalAlignment = VerticalAlignment.Center;
        MemoryStream ms = new MemoryStream();
        book.Write(ms);
        System.Web.HttpContext.Current.Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}.xls", HttpUtility.UrlEncode(title + "_" + DateTime.Now.ToString("yyyy-MM-dd"), System.Text.Encoding.UTF8)));
        System.Web.HttpContext.Current.Response.BinaryWrite(ms.ToArray());
        System.Web.HttpContext.Current.Response.End();
        book = null;
        ms.Close();
        ms.Dispose();

合并单元格 设置样式 输入公式

NPOI的下载地址：http://npoi.codeplex.com/

NPOI的使用教程（中文）：http://tonyqus.sinaapp.com/

首先建立一个空白的工作簿用作测试，并在其中建立空白工作表，在表中建立空白行，在行中建立单元格，并填入内容：
　
//建立空白工作簿
IWorkbook workbook = new HSSFWorkbook();
//在工作簿中：建立空白工作表
ISheet sheet = workbook.CreateSheet();
//在工作表中：建立行，参数为行号，从0计
IRow row = sheet.CreateRow(0);
//在行中：建立单元格，参数为列号，从0计
ICell cell = row.CreateCell(0);
//设置单元格内容
cell.SetCellValue("实习鉴定表");


设置单元格样式：设置单元格样式时需要注意，务必创建一个新的样式对象进行设置，否则会将工作表所有单元格的样式一同设置，它们应该共享的是一个样式对象：
　
ICellStyle style = workbook.CreateCellStyle();
//设置单元格的样式：水平对齐居中
style.Alignment = HorizontalAlignment.CENTER;
//新建一个字体样式对象
IFont font = workbook.CreateFont();
//设置字体加粗样式
font.Boldweight = short.MaxValue;
//使用SetFont方法将字体样式添加到单元格样式中 
style.SetFont(font);
//将新的样式赋给单元格
cell.CellStyle = style;


设置单元格宽高：
　　设置单元格的高度实际是设置其所在行高，所以要在单元格所在行上设置行高，行高设置数值好像是像素点的1/20，所以*20以便达到设置效果；
　　设置单元格的宽度实际上是设置其所在列宽，所以要在单元格所在列上设置（列的设置在工作表上），宽度数值好像是字符的1/256，所以*256以便达到设置效果。
　
//设置单元格的高度
row.Height = 30 * 20;
//设置单元格的宽度
sheet.SetColumnWidth(0, 30 * 256);
 
合并单元格：合并单元格实际上是声明一个区域，该区域中的单元格将进行合并，合并后的内容与样式以该区域最左上角的单元格为准。
 
//设置一个合并单元格区域，使用上下左右定义CellRangeAddress区域
//CellRangeAddress四个参数为：起始行，结束行，起始列，结束列
sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, 10));

添加公式：使用Cell的CellFormula来设置公式，是一个字符串，公式前不需要加=号。
 
//通过Cell的CellFormula向单元格中写入公式
//注：直接写公式内容即可，不需要在最前加'='
ICell cell2 = sheet.CreateRow(1).CreateCell(0);
cell2.CellFormula = "HYPERLINK("测试图片.jpg","测试图片.jpg")";
将工作簿写入文件查看效果：

//将工作簿写入文件
using (FileStream fs = new FileStream("生成效果.xls", FileMode.Create, FileAccess.Write))
{
    workbook.Write(fs);
}

 NPOI导出Excel超过65536会报异常

        //65536判断处理
        public static HSSFWorkbook BuildWorkbook(DataTable dt)
        {
            var book = new HSSFWorkbook();

            ISheet sheet1 = book.CreateSheet("Sheet1");
            ISheet sheet2 = book.CreateSheet("Sheet2");

            //填充数据
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                if (i < 65536)
                {
                    IRow drow = sheet1.CreateRow(i);
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        ICell cell = drow.CreateCell(j, CellType.String);
                        cell.SetCellValue(dt.Rows[i][j].ToString());
                    }
                }
                if (i >= 65536)
                {
                    IRow drow = sheet2.CreateRow(i - 65536);
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        ICell cell = drow.CreateCell(j, CellType.String);
                        cell.SetCellValue(dt.Rows[i][j].ToString());
                    }
                }

            }

            //自动列宽
            for (int i = 0; i <= dt.Columns.Count; i++)
            {
                sheet1.AutoSizeColumn(i, true);
                sheet2.AutoSizeColumn(i, true);
            }
            return book;
        }

使用时需引用需要引用所有5个dll

using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;

/// <summary>
        /// Excel导入成Datable
        /// </summary>
        /// <param name="file">导入路径(包含文件名与扩展名)</param>
        /// <returns></returns>
        public static DataTable ExcelToTable(string file)
        {
            DataTable dt = new DataTable();
            IWorkbook workbook;
            string fileExt = Path.GetExtension(file).ToLower();
            using (FileStream fs = new FileStream(file, FileMode.Open, FileAccess.Read))
            {
                //XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
                if (fileExt == ".xlsx") { workbook = new XSSFWorkbook(fs); } else if (fileExt == ".xls") { workbook = new HSSFWorkbook(fs); } else { workbook = null; }
                if (workbook == null) { return null; }
                ISheet sheet = workbook.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 = GetValueType(header.GetCell(i));
                    if (obj == null || obj.ToString() == string.Empty)
                    {
                        dt.Columns.Add(new DataColumn("Columns" + i.ToString()));
                    }
                    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] = GetValueType(sheet.GetRow(i).GetCell(j));
                        if (dr[j] != null && dr[j].ToString() != string.Empty)
                        {
                            hasValue = true;
                        }
                    }
                    if (hasValue)
                    {
                        dt.Rows.Add(dr);
                    }
                }
            }
            return dt;
        }

        /// <summary>
        /// Datable导出成Excel
        /// </summary>
        /// <param name="dt"></param>
        /// <param name="file">导出路径(包括文件名与扩展名)</param>
        public static void TableToExcel(DataTable dt, string file)
        {
            IWorkbook workbook;
            string fileExt = Path.GetExtension(file).ToLower();
            if (fileExt == ".xlsx") { workbook = new XSSFWorkbook(); } else if (fileExt == ".xls") { workbook = new HSSFWorkbook(); } else { workbook = null; }
            if (workbook == null) { return; }
            ISheet sheet = string.IsNullOrEmpty(dt.TableName) ? workbook.CreateSheet("Sheet1") : workbook.CreateSheet(dt.TableName);

            //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();
            workbook.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
        /// </summary>
        /// <param name="cell"></param>
        /// <returns></returns>
        private static object GetValueType(ICell 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;
            }
        }

时间格式问题：

                case CellType.Numeric: //NUMERIC:  
                    if (DateUtil.IsCellDateFormatted(cell))
                    {
                        return cell.DateCellValue.ToString();
                    }
                    else
                    {
                        return cell.NumericCellValue;
                    }

基于.xls模板生成Excel文件有时间再看

代码下载：https://yunpan.cn/cRBVnTCSchz7k （提取码：779e）