通用类 ExcelHelper Excel操作

/// <summary>
    /// Excel操作
    /// </summary>
    public class ExcelHelper
    {
        /// <summary>  
        /// DataTable导出到Excel的MemoryStream  
        /// </summary>  
        /// <param name="dtSource">源DataTable</param>  
        /// <param name="strHeaderText">表头文本</param>  
        public static MemoryStream GetExcelStream(DataTable dtSource, string strHeaderText)
        {
            HSSFWorkbook workbook = new HSSFWorkbook();
            ISheet sheet = workbook.CreateSheet();

            #region 右击文件 属性信息
            {
                DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
                dsi.Company = "";
                workbook.DocumentSummaryInformation = dsi;

                SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
                si.Author = ""; //填加xls文件作者信息  
                si.ApplicationName = ""; //填加xls文件创建程序信息  
                si.LastAuthor = ""; //填加xls文件最后保存者信息  
                si.Comments = ""; //填加xls文件作者信息  
                si.Title = ""; //填加xls文件标题信息  
                si.Subject = "";//填加文件主题信息  
                si.CreateDateTime = DateTime.Now;
                workbook.SummaryInformation = si;
            }
            #endregion

            ICellStyle dateStyle = workbook.CreateCellStyle();
            IDataFormat format = workbook.CreateDataFormat();
            dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd");

            //取得列宽  
            int[] arrColWidth = new int[dtSource.Columns.Count];
            foreach(DataColumn item in dtSource.Columns)
            {
                arrColWidth[item.Ordinal] = Encoding.GetEncoding(936).GetBytes(item.ColumnName.ToString()).Length;
            }
            for(int i = 0; i < dtSource.Rows.Count; i++)
            {
                for(int j = 0; j < dtSource.Columns.Count; j++)
                {
                    int intTemp = Encoding.GetEncoding(936).GetBytes(dtSource.Rows[i][j].ToString()).Length;
                    if(intTemp > arrColWidth[j])
                    {
                        arrColWidth[j] = intTemp;
                    }
                }
            }



            int rowIndex = 0;

            foreach(DataRow row in dtSource.Rows)
            {
                #region 新建表，填充表头，填充列头，样式
                if(rowIndex == 65535 || rowIndex == 0)
                {
                    if(rowIndex != 0)
                    {
                        sheet = workbook.CreateSheet();
                    }

                    #region 表头及样式
                    if (!string.IsNullOrEmpty(strHeaderText))
                    {
                        IRow headerRow = sheet.CreateRow(0);
                        headerRow.HeightInPoints = 25;
                        headerRow.CreateCell(0).SetCellValue(strHeaderText);

                        ICellStyle headStyle = workbook.CreateCellStyle();
                        headStyle.Alignment = HorizontalAlignment.CENTER;
                        IFont font = workbook.CreateFont();
                        font.FontHeightInPoints = 20;
                        font.Boldweight = 700;
                        headStyle.SetFont(font);

                        headerRow.GetCell(0).CellStyle = headStyle;
                        sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, dtSource.Columns.Count - 1));

                    }
                    #endregion


                    #region 列头及样式
                    {
                        IRow headerRow = sheet.CreateRow(1);


                        ICellStyle headStyle = workbook.CreateCellStyle();
                        headStyle.Alignment = HorizontalAlignment.CENTER;
                        IFont font = workbook.CreateFont();
                        font.FontHeightInPoints = 10;
                        font.Boldweight = 700;
                        headStyle.SetFont(font);


                        foreach(DataColumn column in dtSource.Columns)
                        {
                            headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
                            headerRow.GetCell(column.Ordinal).CellStyle = headStyle;

                            //设置列宽  
                            sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256);

                        }

                    }
                    #endregion

                    rowIndex = 2;
                }
                #endregion


                #region 填充内容
                IRow dataRow = sheet.CreateRow(rowIndex);
                foreach(DataColumn column in dtSource.Columns)
                {
                    ICell newCell = dataRow.CreateCell(column.Ordinal);

                    string drValue = row[column].ToString();

                    switch(column.DataType.ToString())
                    {
                        case "System.String"://字符串类型  
                            newCell.SetCellValue(drValue);
                            break;
                        case "System.DateTime"://日期类型  
                            DateTime dateV;
                            DateTime.TryParse(drValue, out dateV);
                            newCell.SetCellValue(dateV);

                            newCell.CellStyle = dateStyle;//格式化显示  
                            break;
                        case "System.Boolean"://布尔型  
                            bool boolV = false;
                            bool.TryParse(drValue, out boolV);
                            newCell.SetCellValue(boolV);
                            break;
                        case "System.Int16"://整型  
                        case "System.Int32":
                        case "System.Int64":
                        case "System.Byte":
                            int intV = 0;
                            int.TryParse(drValue, out intV);
                            newCell.SetCellValue(intV);
                            break;
                        case "System.Decimal"://浮点型  
                        case "System.Double":
                            double doubV = 0;
                            double.TryParse(drValue, out doubV);
                            newCell.SetCellValue(doubV);
                            break;
                        case "System.DBNull"://空值处理  
                            newCell.SetCellValue("");
                            break;
                        default:
                            newCell.SetCellValue("");
                            break;
                    }

                }
                #endregion

                rowIndex++;
            }


            using(MemoryStream ms = new MemoryStream())
            {
                workbook.Write(ms);
                ms.Flush();
                ms.Position = 0;

                workbook.Dispose();
                return ms;
            }

        }


        /// <summary>  
        /// 导出Excel
        /// </summary>  
        /// <param name="dtSource">源DataTable</param>  
        /// <param name="strHeaderText">表头文本</param>  
        /// <param name="strFileName">文件名</param>  
        public static void Export(DataTable dtSource, string strHeaderText, string strFileName)
        {
            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 = "UTF-8";

            if (curContext.Request.ServerVariables["HTTP_USER_AGENT"].IndexOf("Firefox") > -1)
            {
                curContext.Response.AddHeader("Content-Disposition", "attachment;FileName=" + strFileName);
            }
            else
            {
                curContext.Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(strFileName, Encoding.UTF8)); 
            }            
            curContext.Response.BinaryWrite(GetExcelStream(dtSource, strHeaderText).GetBuffer());
            curContext.Response.End();
        }
            
        /// <summary>
        /// 读取excel  
        /// 默认第一行为标头  
        /// </summary>  
        /// <param name="strFileName">excel文档路径</param>  
        /// <returns></returns>  
        public static DataTable Import(string strFileName)
        {
            DataTable dt = new DataTable();

            HSSFWorkbook hssfworkbook;
            using(FileStream file = new FileStream(strFileName, FileMode.Open, FileAccess.Read))
            {
                hssfworkbook = new HSSFWorkbook(file);
            }
            ISheet sheet = hssfworkbook.GetSheetAt(0);
            System.Collections.IEnumerator rows = sheet.GetRowEnumerator();

            IRow headerRow = sheet.GetRow(0);
            int cellCount = headerRow.LastCellNum;

            for(int j = 0; j < cellCount; j++)
            {
                ICell cell = headerRow.GetCell(j);
                dt.Columns.Add(cell.ToString());
            }

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

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

                dt.Rows.Add(dataRow);
            }
            return dt;
        }


    }