使用NPOI操纵Excle，并输入到客户端

NPOI下载：http://files.cnblogs.com/files/gosky/NPOI_2.2.0.0.zip

导入以下5个引用：

ICSharpCode.SharpZipLib.dll

NPOI.dll

NPOI.OOXML.dll

NPOI.OpenXml4Net.dll

NPOI.OpenXmlFormats.dll

1.将Excle数据导入到DataTable中

新建工具类： 根据上传文件后缀名判断 xls使用 ImportExcelFile2003方法 xlsx使用ImportExcelFile2007方法

using NPOI.XSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.HSSF.UserModel;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Text;
using NPOI.SS.Formula.Eval;
/// <summary>
/// NPOIExcelHelper 的摘要说明
/// </summary>
public class NPOIExcelHelper
{

    public static DataTable ImportExcelFile2007(string filePath)
    {

        XSSFWorkbook hssfworkbook;
        #region//初始化信息
        try
        {
            using (FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
            {
                hssfworkbook = new XSSFWorkbook(file);;
            }
        }
        catch (Exception e)
        {
            throw e;
        }
        #endregion

        NPOI.SS.UserModel.ISheet sheet = hssfworkbook.GetSheetAt();;
        System.Collections.IEnumerator rows = sheet.GetRowEnumerator();;
        DataTable dt = new DataTable();;
        rows.MoveNext();;

        XSSFRow row = (XSSFRow)rows.Current;
        for (int j = ; j < (sheet.GetRow().LastCellNum); j++)
        {
            //dt.Columns.Add(Convert.ToChar(((int)'A') + j).ToString());;
            //将第一列作为列表头
            dt.Columns.Add(row.GetCell(j).ToString());;
        }
        while (rows.MoveNext())
        {
            row = (XSSFRow)rows.Current;
            DataRow dr = dt.NewRow();;
            for (int i = ; i < row.LastCellNum; i++)
            {
                NPOI.SS.UserModel.ICell cell = row.GetCell(i);;
                if (cell == null)
                {
                    dr[i] = null;
                }
                else
                {
                    dr[i] = cell.ToString();;
                }
            }
            dt.Rows.Add(dr);;
        }
        return dt;
    }

    public static DataTable ImportExcelFile2003(string filePath)
    {

        HSSFWorkbook hssfworkbook;
        #region//初始化信息
        try
        {
            using (FileStream file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
            {
                hssfworkbook = new HSSFWorkbook(file);;
            }
        }
        catch (Exception e)
        {
            throw e;
        }
        #endregion

        NPOI.SS.UserModel.ISheet sheet = hssfworkbook.GetSheetAt();;
        System.Collections.IEnumerator rows = sheet.GetRowEnumerator();;
        DataTable dt = new DataTable();;
        rows.MoveNext();;

        HSSFRow row = (HSSFRow)rows.Current;
        for (int j = ; j < (sheet.GetRow().LastCellNum); j++)
        {
            //dt.Columns.Add(Convert.ToChar(((int)'A') + j).ToString());;
            //将第一列作为列表头
            dt.Columns.Add(row.GetCell(j).ToString());;
        }
        while (rows.MoveNext())
        {
            row = (HSSFRow)rows.Current;
            DataRow dr = dt.NewRow();;
            for (int i = ; i < row.LastCellNum; i++)
            {
                NPOI.SS.UserModel.ICell cell = row.GetCell(i);;
                if (cell == null)
                {
                    dr[i] = null;
                }
                else
                {
                    dr[i] = cell.ToString();;
                }
            }
            dt.Rows.Add(dr);;
        }
        return dt;
    }

}

2.将数据导出到Excle

引用命名空间：

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

代码实例：

//创建工作簿
HSSFWorkbook workbook = new HSSFWorkbook();
//创建标签
ISheet sheet = workbook.CreateSheet("sheet1");
//新建表头
IRow rowHead = sheet.CreateRow();
rowHead.CreateCell(, CellType.String).SetCellValue("序号");
rowHead.CreateCell(, CellType.String).SetCellValue("学生姓名");
rowHead.CreateCell(, CellType.String).SetCellValue("性别");
rowHead.CreateCell(, CellType.String).SetCellValue("生源地");
rowHead.CreateCell(, CellType.String).SetCellValue("身份证");
rowHead.CreateCell(, CellType.String).SetCellValue("准考证");
rowHead.CreateCell(, CellType.String).SetCellValue("专业名称");
rowHead.CreateCell(, CellType.String).SetCellValue("专业方向");
rowHead.CreateCell(, CellType.String).SetCellValue("来源");
rowHead.CreateCell(, CellType.String).SetCellValue("生源学校");
rowHead.CreateCell(, CellType.String).SetCellValue("审核状态");
rowHead.CreateCell(, CellType.String).SetCellValue("录取状态");
//循环填充内容
for (int i = ; i < table.Rows.Count; i++)
{
    IRow row = sheet.CreateRow(i + );
    DataRow datarow = table.Rows[i];
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["rn"]));
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["StuName"]));
    row.CreateCell(, CellType.String).SetCellValue(Constants.sex[datarow["StuSex"].ToString()]);
    row.CreateCell(, CellType.String).SetCellValue(Constants.stuAddr[datarow["StuProvince"].ToString()] + Constants.stuAddr[datarow["StuCity"].ToString()]);
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["StuCardNo"]));
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["StuZKNo"]));
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["zyname"]));
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["zyfx"]));
    row.CreateCell(, CellType.String).SetCellValue(Constants.stuFrom[datarow["StuFrom"].ToString()]);
    row.CreateCell(, CellType.String).SetCellValue(Convert.ToString(datarow["StuSchool"]));
    row.CreateCell(, CellType.String).SetCellValue(Constants.stuState[datarow["State"].ToString()]);
    row.CreateCell(, CellType.String).SetCellValue(Constants.stuAdmit[datarow["Admit"].ToString()]);
}

System.IO.MemoryStream ms = new System.IO.MemoryStream();
//写入内存
workbook.Write(ms);
Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}.xls", DateTime.Now.ToString("yyyyMMddHHmmssfff")));
//输出到客户端
Response.BinaryWrite(ms.ToArray());
workbook = null;
ms.Close();
ms.Dispose();

导出结果如图：

3.将服务器上的文件输出到客户端

//读取文件
FileStream fileStream = new FileStream(Server.MapPath("~/Uploads/test.xlsx"), FileMode.Open);
long fileSize = fileStream.Length;
byte[] fileBuffer = new byte[fileSize];
fileStream.Read(fileBuffer, , (int)fileSize);
//如果不写fileStream.Close()语句，用户在下载过程中选择取消，将不能再次下载
fileStream.Close();
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}.xlsx", DateTime.Now.ToString("yyyyMMdd")));
Response.AddHeader("Content-Length", fileSize.ToString());
Response.BinaryWrite(fileBuffer);
Response.Flush();
Response.Close();

将服务器上 /Uploads/test.xlsx 文件 输出到客户端并使用日期命名