NPOIHelper导出excel

手写一个通用类，导出excel ，方便快捷

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.IO;
using System.Text;
using NPOI;
using NPOI.HPSF;
using NPOI.HSSF;
using NPOI.SS.UserModel;
using NPOI.HSSF.Util;
using NPOI.POIFS;
using NPOI.Util;
using NPOI.HSSF.UserModel;
using System.Reflection;
using System.Collections.Generic;

namespace DA.Utils
{
    public class NPOIHelper
    {
        /// <summary>
        /// DataTable导出到Excel文件
        /// </summary>
        /// <param name="dtSource">源DataTable</param>
        /// <param name="strHeaderText">表头文本</param>
        /// <param name="strFileName">保存位置</param>
        public static void Export(DataTable dtSource, string strHeaderText, string strFileName)
        {
            using (MemoryStream ms = Export(dtSource, strHeaderText))
            {
                using (FileStream fs = new FileStream(strFileName, FileMode.Create, FileAccess.Write))
                {
                    byte[] data = ms.ToArray();
                    fs.Write(data, 0, data.Length);
                    fs.Flush();
                }
            }
        }

        /// <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 Export(DataTable dtSource, string strHeaderText)
        {
            HSSFWorkbook workbook = new HSSFWorkbook();
            //HSSFSheet sheet = workbook.CreateSheet();
            NPOI.SS.UserModel.ISheet sheet = workbook.CreateSheet();
            #region 右击文件 属性信息
            {
                DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
                dsi.Company = "NPOI";
                workbook.DocumentSummaryInformation = dsi;

                SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
                si.Author = "文件作者信息"; //填加xls文件作者信息
                si.ApplicationName = "创建程序信息"; //填加xls文件创建程序信息
                si.LastAuthor = "最后保存者信息"; //填加xls文件最后保存者信息
                si.Comments = "作者信息"; //填加xls文件作者信息
                si.Title = "标题信息"; //填加xls文件标题信息

                si.Subject = "主题信息";//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
                    {
                        //HSSFRow headerRow = sheet.CreateRow(0);
                        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 NPOI.SS.Util.CellRangeAddress(0, 0, 0, dtSource.Columns.Count - 1));

                        // headerRow.Dispose();
                    }
                    #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);
                        }
                        //headerRow.Dispose();
                    }
                    #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;

                //sheet.Dispose();
                //workbook.Dispose();//一般只用写这一个就OK了，他会遍历并释放所有资源，但当前版本有问题所以只释放sheet
                return ms;
            }
        }

        /// <summary>
        /// 用于Web导出
        /// </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 ExportByWeb(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 = "";
            curContext.Response.AppendHeader("Content-Disposition",
                "attachment;filename=" + HttpUtility.UrlEncode(strFileName, Encoding.UTF8));

            curContext.Response.BinaryWrite(Export(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;
        }

        /// <summary>
        /// List集合转DataTable
        /// </summary>
        /// <typeparam name="T">实体类型</typeparam>
        /// <param name="list">传入集合</param>
        /// <returns>返回datatable结果</returns>
        public static DataTable ListToTable<T>(List<T> list)
        {
            Type tp = typeof(T);
            PropertyInfo[] proInfos = tp.GetProperties();
            DataTable dt = new DataTable();
            foreach (var item in proInfos)
            {
                dt.Columns.Add(item.Name, item.PropertyType); //添加列明及对应类型
            }
            foreach (var item in list)
            {
                DataRow dr = dt.NewRow();
                foreach (var proInfo in proInfos)
                {
                    object obj = proInfo.GetValue(item);
                    if (obj == null)
                    {
                        continue;
                    }
                    dr[proInfo.Name] = obj;
                }
                dt.Rows.Add(dr);
            }
            return dt;
        }
    }
}

实际调用方法

public async Task<ActionResult> ExportExcelByWeb(string fromUrl)
        {
            var userList = await DbQueryContext.Query<xxxx>().ToListAsync();
            foreach (var item in userList)
            {
                var uuid = string.Empty;
                //UUId为空创建sssId(未进入过“绑xxxx界面，进入会自动生成)
                if (string.IsNullOrEmpty(item.UUId))
                {
                    uuid = await CommandSender.SendAndReturnAsync(new CreateUUIdCommand
                    {
                        UserId = item.Id
                    }, m => m.ReturnUUId);
                }
                if (string.IsNullOrEmpty(item.AccountNumberName))
                {
                    await CommandSender.SendAsync(new BindAccountCommand
                    {
                        UserId = item.Id,
                        AccountNumberName = item.UserName
                    });
                }

            }
            var user = await DbQueryContext.Query<User>().Select(m => new { m.AccountNumberName, m.UUId, m.Name, m.DepartmentName, m.JobName, m.Enabled, m.Phone, m.Email, m.UserName }).ToListAsync();
            var userDataTable = Utils.NPOIHelper.ListToTable(user);
            userDataTable.Columns["AccountNumberName"].ColumnName = "第xxxx";
            userDataTable.Columns["UUId"].ColumnName = "xxxx";
            userDataTable.Columns["Name"].ColumnName = "用户xxxx";
            userDataTable.Columns["DepartmentName"].ColumnName = "xxxx";
            userDataTable.Columns["JobName"].ColumnName = "xxxx";
            userDataTable.Columns["Enabled"].ColumnName = "xxxx";
            userDataTable.Columns["Phone"].ColumnName = "xxxx";
            userDataTable.Columns["Email"].ColumnName = "xxxx";
            userDataTable.Columns["UserName"].ColumnName = "xxxx号";
            Utils.NPOIHelper.ExportByWeb(userDataTable, "xxxx", "xxxx.xls");

            return TipsOk(fromUrl);
        }