NPOI操作Excel类

NPOI是基于POI开发,是一种不需要Office插件既能操作Excel,Work等

public class ExcelRender
    {
        /// <summary>
        /// 根据Excel列类型获取列的值
        /// </summary>
        /// <param name="cell">Excel列</param>
        /// <returns></returns>
        private static string GetCellValue(ICell cell)
        {
            if (cell == null)
                return string.Empty;
            switch (cell.CellType)
            {
                case CellType.BLANK:
                    return string.Empty;
                case CellType.BOOLEAN:
                    return cell.BooleanCellValue.ToString();
                case CellType.ERROR:
                    return cell.ErrorCellValue.ToString();
                case CellType.NUMERIC:
                case CellType.Unknown:
                default:
                    return cell.ToString();//This is a trick to get the correct value of the cell. NumericCellValue will return a numeric value no matter the cell value is a date or a number
                case CellType.STRING:
                    return cell.StringCellValue;
                case CellType.FORMULA:
                    try
                    {
                        HSSFFormulaEvaluator e = new HSSFFormulaEvaluator(cell.Sheet.Workbook);
                        e.EvaluateInCell(cell);
                        return cell.ToString();
                    }
                    catch
                    {
                        return cell.NumericCellValue.ToString();
                    }
            }
        }

        /// <summary>
        /// 自动设置Excel列宽
        /// </summary>
        /// <param name="sheet">Excel表</param>
        private static void AutoSizeColumns(ISheet sheet)
        {
            if (sheet.PhysicalNumberOfRows > 0)
            {
                IRow headerRow = sheet.GetRow(0);

                for (int i = 0, l = headerRow.LastCellNum; i < l; i++)
                {
                    sheet.AutoSizeColumn(i);
                }
            }
        }

        /// <summary>
        /// 保存Excel文档流到文件
        /// </summary>
        /// <param name="ms">Excel文档流</param>
        /// <param name="fileName">文件名</param>
        private static void SaveToFile(MemoryStream ms, string fileName)
        {
            using (FileStream fs = new FileStream(fileName, FileMode.Create, FileAccess.Write))
            {
                byte[] data = ms.ToArray();

                fs.Write(data, 0, data.Length);
                fs.Flush();

                data = null;
            }
        }

        /// <summary>
        /// 输出文件到浏览器
        /// </summary>
        /// <param name="ms">Excel文档流</param>
        /// <param name="context">HTTP上下文</param>
        /// <param name="fileName">文件名</param>
        private static void RenderToBrowser(MemoryStream ms, HttpContext context, string fileName)
        {
            if (context.Request.Browser.Browser == "IE")
                fileName = HttpUtility.UrlEncode(fileName);
            context.Response.AddHeader("Content-Disposition", "attachment;fileName=" + fileName);
            context.Response.BinaryWrite(ms.ToArray());
        }

        /// <summary>
        /// DataReader转换成Excel文档流
        /// </summary>
        /// <param name="reader"></param>
        /// <returns></returns>
        public static MemoryStream RenderToExcel(IDataReader reader)
        {
            MemoryStream ms = new MemoryStream();

            using (reader)
            {
                using (IWorkbook workbook = new HSSFWorkbook())
                {
                    using (ISheet sheet = workbook.CreateSheet())
                    {
                        IRow headerRow = sheet.CreateRow(0);
                        int cellCount = reader.FieldCount;

                        // handling header.
                        for (int i = 0; i < cellCount; i++)
                        {
                            headerRow.CreateCell(i).SetCellValue(reader.GetName(i));
                        }

                        // handling value.
                        int rowIndex = 1;
                        while (reader.Read())
                        {
                            IRow dataRow = sheet.CreateRow(rowIndex);

                            for (int i = 0; i < cellCount; i++)
                            {
                                dataRow.CreateCell(i).SetCellValue(reader[i].ToString());
                            }

                            rowIndex++;
                        }

                        AutoSizeColumns(sheet);

                        workbook.Write(ms);
                        ms.Flush();
                        ms.Position = 0;
                    }
                }
            }
            return ms;
        }

        /// <summary>
        /// DataReader转换成Excel文档流,并保存到文件
        /// </summary>
        /// <param name="reader"></param>
        /// <param name="fileName">保存的路径</param>
        public static void RenderToExcel(IDataReader reader, string fileName)
        {
            using (MemoryStream ms = RenderToExcel(reader))
            {
                SaveToFile(ms, fileName);
            }
        }

        /// <summary>
        /// DataReader转换成Excel文档流,并输出到客户端
        /// </summary>
        /// <param name="reader"></param>
        /// <param name="context">HTTP上下文</param>
        /// <param name="fileName">输出的文件名</param>
        public static void RenderToExcel(IDataReader reader, HttpContext context, string fileName)
        {
            using (MemoryStream ms = RenderToExcel(reader))
            {
                RenderToBrowser(ms, context, fileName);
            }
        }

        /// <summary>
        /// DataTable转换成Excel文档流
        /// </summary>
        /// <param name="table"></param>
        /// <returns></returns>
        public static MemoryStream RenderToExcel(DataTable table)
        {
            MemoryStream ms = new MemoryStream();

            using (table)
            {
                using (IWorkbook workbook = new HSSFWorkbook())
                {
                    using (ISheet sheet = workbook.CreateSheet())
                    {
                        IRow headerRow = sheet.CreateRow(0);

                        // handling header.
                        foreach (DataColumn column in table.Columns)
                            headerRow.CreateCell(column.Ordinal).SetCellValue(column.Caption);//If Caption not set, returns the ColumnName value

                        // handling value.
                        int rowIndex = 1;

                        foreach (DataRow row in table.Rows)
                        {
                            IRow dataRow = sheet.CreateRow(rowIndex);

                            foreach (DataColumn column in table.Columns)
                            {
                                dataRow.CreateCell(column.Ordinal).SetCellValue(row[column].ToString());
                            }

                            rowIndex++;
                        }
                        AutoSizeColumns(sheet);

                        workbook.Write(ms);
                        ms.Flush();
                        ms.Position = 0;
                    }
                }
            }
            return ms;
        }

        /// <summary>
        /// DataTable转换成Excel文档流,并保存到文件
        /// </summary>
        /// <param name="table"></param>
        /// <param name="fileName">保存的路径</param>
        public static void RenderToExcel(DataTable table, string fileName)
        {
            using (MemoryStream ms = RenderToExcel(table))
            {
                SaveToFile(ms, fileName);
            }
        }

        /// <summary>
        /// DataTable转换成Excel文档流,并输出到客户端
        /// </summary>
        /// <param name="table"></param>
        /// <param name="response"></param>
        /// <param name="fileName">输出的文件名</param>
        public static void RenderToExcel(DataTable table, HttpContext context, string fileName)
        {
            using (MemoryStream ms = RenderToExcel(table))
            {
                RenderToBrowser(ms, context, fileName);
            }
        }

        /// <summary>
        /// Excel文档流是否有数据
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <returns></returns>
        public static bool HasData(Stream excelFileStream)
        {
            return HasData(excelFileStream, 0);
        }

        /// <summary>
        /// Excel文档流是否有数据
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="sheetIndex">表索引号,如第一个表为0</param>
        /// <returns></returns>
        public static bool HasData(Stream excelFileStream, int sheetIndex)
        {
            using (excelFileStream)
            {
                using (IWorkbook workbook = new HSSFWorkbook(excelFileStream))
                {
                    if (workbook.NumberOfSheets > 0)
                    {
                        if (sheetIndex < workbook.NumberOfSheets)
                        {
                            using (ISheet sheet = workbook.GetSheetAt(sheetIndex))
                            {
                                return sheet.PhysicalNumberOfRows > 0;
                            }
                        }
                    }
                }
            }
            return false;
        }

        /// <summary>
        /// Excel文档流转换成DataTable
        /// 第一行必须为标题行
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="sheetName">表名称</param>
        /// <returns></returns>
        public static DataTable RenderFromExcel(Stream excelFileStream, string sheetName)
        {
            return RenderFromExcel(excelFileStream, sheetName, 0);
        }

        /// <summary>
        /// Excel文档流转换成DataTable
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="sheetName">表名称</param>
        /// <param name="headerRowIndex">标题行索引号,如第一行为0</param>
        /// <returns></returns>
        public static DataTable RenderFromExcel(Stream excelFileStream, string sheetName, int headerRowIndex)
        {
            DataTable table = null;

            using (excelFileStream)
            {
                using (IWorkbook workbook = new HSSFWorkbook(excelFileStream))
                {
                    using (ISheet sheet = workbook.GetSheet(sheetName))
                    {
                        table = RenderFromExcel(sheet, headerRowIndex);
                    }
                }
            }
            return table;
        }

        /// <summary>
        /// Excel文档流转换成DataTable
        /// 默认转换Excel的第一个表
        /// 第一行必须为标题行
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <returns></returns>
        public static DataTable RenderFromExcel(Stream excelFileStream)
        {
            return RenderFromExcel(excelFileStream, 0, 0);
        }

        /// <summary>
        /// Excel文档流转换成DataTable
        /// 第一行必须为标题行
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="sheetIndex">表索引号,如第一个表为0</param>
        /// <returns></returns>
        public static DataTable RenderFromExcel(Stream excelFileStream, int sheetIndex)
        {
            return RenderFromExcel(excelFileStream, sheetIndex, 0);
        }

        /// <summary>
        /// Excel文档流转换成DataTable
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="sheetIndex">表索引号,如第一个表为0</param>
        /// <param name="headerRowIndex">标题行索引号,如第一行为0</param>
        /// <returns></returns>
        public static DataTable RenderFromExcel(Stream excelFileStream, int sheetIndex, int headerRowIndex)
        {
            DataTable table = null;

            using (excelFileStream)
            {
                using (IWorkbook workbook = new HSSFWorkbook(excelFileStream))
                {
                    using (ISheet sheet = workbook.GetSheetAt(sheetIndex))
                    {
                        table = RenderFromExcel(sheet, headerRowIndex);
                    }
                }
            }
            return table;
        }

        /// <summary>
        /// Excel表格转换成DataTable
        /// </summary>
        /// <param name="sheet">表格</param>
        /// <param name="headerRowIndex">标题行索引号,如第一行为0</param>
        /// <returns></returns>
        private static DataTable RenderFromExcel(ISheet sheet, int headerRowIndex)
        {
            DataTable table = new DataTable();

            IRow headerRow = sheet.GetRow(headerRowIndex);
            int cellCount = headerRow.LastCellNum;//LastCellNum = PhysicalNumberOfCells
            int rowCount = sheet.LastRowNum;//LastRowNum = PhysicalNumberOfRows - 1

            //handling header.
            for (int i = headerRow.FirstCellNum; i < cellCount; i++)
            {
                DataColumn column = new DataColumn(headerRow.GetCell(i).StringCellValue);
                table.Columns.Add(column);
            }

            for (int i = (sheet.FirstRowNum + 1); i <= rowCount; i++)
            {
                IRow row = sheet.GetRow(i);
                DataRow dataRow = table.NewRow();

                if (row != null)
                {
                    for (int j = row.FirstCellNum; j < cellCount; j++)
                    {
                        if (row.GetCell(j) != null)
                            dataRow[j] = GetCellValue(row.GetCell(j));
                    }
                }

                table.Rows.Add(dataRow);
            }

            return table;
        }

        /// <summary>
        /// Excel文档导入到数据库
        /// 默认取Excel的第一个表
        /// 第一行必须为标题行
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="insertSql">插入语句</param>
        /// <param name="dbAction">更新到数据库的方法</param>
        /// <returns></returns>
        public static int RenderToDb(Stream excelFileStream, string insertSql, DBAction dbAction)
        {
            return RenderToDb(excelFileStream, insertSql, dbAction, 0, 0);
        }

        public delegate int DBAction(string sql, params IDataParameter[] parameters);

        /// <summary>
        /// Excel文档导入到数据库
        /// </summary>
        /// <param name="excelFileStream">Excel文档流</param>
        /// <param name="insertSql">插入语句</param>
        /// <param name="dbAction">更新到数据库的方法</param>
        /// <param name="sheetIndex">表索引号,如第一个表为0</param>
        /// <param name="headerRowIndex">标题行索引号,如第一行为0</param>
        /// <returns></returns>
        public static int RenderToDb(Stream excelFileStream, string insertSql, DBAction dbAction, int sheetIndex, int headerRowIndex)
        {
            int rowAffected = 0;
            using (excelFileStream)
            {
                using (IWorkbook workbook = new HSSFWorkbook(excelFileStream))
                {
                    using (ISheet sheet = workbook.GetSheetAt(sheetIndex))
                    {
                        StringBuilder builder = new StringBuilder();

                        IRow headerRow = sheet.GetRow(headerRowIndex);
                        int cellCount = headerRow.LastCellNum;//LastCellNum = PhysicalNumberOfCells
                        int rowCount = sheet.LastRowNum;//LastRowNum = PhysicalNumberOfRows - 1

                        for (int i = (sheet.FirstRowNum + 1); i <= rowCount; i++)
                        {
                            IRow row = sheet.GetRow(i);
                            if (row != null)
                            {
                                builder.Append(insertSql);
                                builder.Append(" values (");
                                for (int j = row.FirstCellNum; j < cellCount; j++)
                                {
                                    builder.AppendFormat("'{0}',", GetCellValue(row.GetCell(j)).Replace("'", "''"));
                                }
                                builder.Length = builder.Length - 1;
                                builder.Append(");");
                            }

                            if ((i % 50 == 0 || i == rowCount) && builder.Length > 0)
                            {
                                //每50条记录一次批量插入到数据库
                                rowAffected += dbAction(builder.ToString());
                                builder.Length = 0;
                            }
                        }
                    }
                }
            }
            return rowAffected;
        }
    }

  

原文地址:https://www.cnblogs.com/Lance-Lan/p/3620282.html