C#生成Excel保存到服务器端并下载

using MongoDB.Bson;
using Newtonsoft.Json.Linq;
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Web;
using System.Web.Http;
using System.Web.Mvc;
using Zluo.CMember.Entity;
using Zluo.CMember.Interface;
using Zluo.CMember.Service;
using Zluo.CMember.Web.RequestParam;
using Zluo.CMember.Web.RequestParam.Account;
using Zluo.CMember.Web.RequestParam.Order;
using Zluo.Common;
using Zluo.Common.CMember;
using Zluo.SessionCached;
public void CreateExport()
        {
            try
            {
                string fileName = "ErrorSongIds.xls"; // 文件名称 
                string filePath = Path.Combine(HttpRuntime.AppDomainAppPath, "Upload") + "/" + fileName;
                // 1.检测是否存在文件夹，若不存在就建立个文件夹 
                string directoryName = Path.GetDirectoryName(filePath); if (!Directory.Exists(directoryName)) { Directory.CreateDirectory(directoryName); }
                // 2.解析单元格头部，设置单元头的中文名称 
                HSSFWorkbook workbook = new HSSFWorkbook();
                // 工作簿 
                ISheet sheet = workbook.CreateSheet("失败歌曲");
                // 工作表 
                IRow row = sheet.CreateRow(0); row.CreateCell(0).SetCellValue("原始ID");
                row.CreateCell(1).SetCellValue("歌曲名称");
                row.CreateCell(2).SetCellValue("歌手名");
                row.CreateCell(3).SetCellValue("失败原因");
                //_songListService.getErrorExcel(uid);
                BsonArray array = null;
                int rowIndex = 1; BsonDocument bd = null;
                if (array != null && array.Count > 0)
                {
                    for (int i = 0; i < array.Count; i++)
                    {
                        IRow rowTmp = sheet.CreateRow(rowIndex);
                        bd = (BsonDocument)array[i];
                        if (bd != null)
                        {
                            rowTmp.CreateCell(0).SetCellValue(bd.GetValue("sourceId").ToString());
                            rowTmp.CreateCell(1).SetCellValue(bd.GetValue("songName").ToString());
                            rowTmp.CreateCell(2).SetCellValue(bd.GetValue("singerName").ToString());
                            rowTmp.CreateCell(3).SetCellValue(string.IsNullOrEmpty(bd.GetValue("errorReason").ToString()) ? "" : bd.GetValue("errorReason").ToString());
                            rowIndex++;
                        }
                    }
                }
                // 4.生成文件 
                FileStream file = new FileStream(filePath, FileMode.Create);
                workbook.Write(file); file.Close();
                Response.AppendHeader("Content-Disposition", "attachment;filename=ErrorSongIds.xls");
                Response.ContentType = "application/ms-excel";
                Response.WriteFile(filePath);
                Response.Flush();
                Response.End();
            }
            catch (Exception ex) { throw ex; }
        }

 由于没有找到哪里上传文件，需要NPOI.dll文件的给我留言哈，见谅咯。

附加动态加载Excel列和合并单元格的代码：

public void CreateExport()
        {
            try
            {string fileName = "Members.xls"; // 文件名称 
                string filePath = Path.Combine(HttpRuntime.AppDomainAppPath, "Template") + "/" + fileName;
                // 1.检测是否存在文件夹，若不存在就建立个文件夹 
                string directoryName = Path.GetDirectoryName(filePath);
                if (!Directory.Exists(directoryName))
                {
                    Directory.CreateDirectory(directoryName);
                }
                // 2.解析单元格头部，设置单元头的中文名称 
                HSSFWorkbook workbook = new HSSFWorkbook();

                // 工作簿 
                ISheet sheet = workbook.CreateSheet("会员列表");

                #region 设置Excel表格第一行的样式
                IRow titleInfo = sheet.CreateRow(0);
                ICell cellTitle = titleInfo.CreateCell(0);
                cellTitle.SetCellValue("会员信息批量录入模板");
                ICellStyle titleStyle = workbook.CreateCellStyle();
                IFont titleFont = workbook.CreateFont();
                titleFont.FontHeightInPoints = 25;
                titleFont.Boldweight = short.MaxValue;//字体加粗 
                titleStyle.SetFont(titleFont);
                cellTitle.CellStyle = titleStyle;

                #endregion


                IRow dataFields = sheet.CreateRow(2);


                ICellStyle style = workbook.CreateCellStyle();//创建样式对象 
                style.Alignment = HorizontalAlignment.CENTER;//水平对齐
                style.VerticalAlignment = VerticalAlignment.CENTER;//垂直对齐
                IFont font = workbook.CreateFont(); //创建一个字体样式对象 
                font.FontName = "宋体"; //和excel里面的字体对应 
                font.Color = new HSSFColor.RED().GetIndex();//颜色参考NPOI的颜色对照表(替换掉PINK()) 
                font.FontHeightInPoints = 10;//字体大小 
                font.Boldweight = short.MaxValue;//字体加粗 
                style.SetFont(font); //将字体样式赋给样式对象
                sheet.SetColumnWidth(0, 20 * 256);//设置列宽

                string[] colums = { "*会员卡号", "*会员手机", "*会员姓名", "*会员等级", "会员性别", "电子邮箱", "会员状态", "固定电话", "永久有效", "身份证号", "开卡费用", "会员地址", "备注信息" };
                ICell Cell = null;
                for (int i = 0; i < colums.Count(); i++)
                {
                    Cell = dataFields.CreateCell(i);
                    Cell.CellStyle = style;
                    Cell.SetCellValue(colums[i]);
                    sheet.SetColumnWidth(i, 17 * 256);
                }
                sheet.AddMergedRegion(new CellRangeAddress(0, 0, 0, colums.Count()));//合并单元格
                // 4.生成文件 
                FileStream file = new FileStream(filePath, FileMode.Create);
                workbook.Write(file); file.Close();
                Response.AppendHeader("Content-Disposition", "attachment;filename=Members.xls");
                Response.ContentType = "application/ms-excel";
                Response.WriteFile(filePath);
                Response.Flush();
                Response.End();
            }
            catch (Exception ex) { throw ex; }
        }