使用NPOI实现excel的导入导出 itprobie

NPOI2可以对excle2003和excle2007进行导入导出的操作

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using System.IO;
using System.Reflection;
using System.Collections;
using System.Data;
using NPOI.SS.UserModel;

/// <summary>
/// Summary description for OfficeHelper
/// </summary>
public class OfficeHelper
{
    DownHelper downHelper = null;
    public OfficeHelper()
    {
        downHelper = new DownHelper();
    }


    /// <summary>
    /// 从excle导入到数据集，excle中的工作表对应dataset中的table，工作表名和列名分别对应table中的表名和列名
    /// </summary>
    /// <param name="path"></param>
    /// <returns></returns>
    public DataSet ExcelToDataSet(string path)
    {
        DataSet ds = new DataSet();
        IWorkbook wb = WorkbookFactory.Create(path);
        for (int sheetIndex = 0; sheetIndex < wb.Count; sheetIndex++)
        {
            ISheet sheet = wb.GetSheetAt(sheetIndex);
            DataTable dt = new DataTable(sheet.SheetName);

            //添加列
            int columnCount = sheet.GetRow(0).PhysicalNumberOfCells;
            for (int i = 0; i < columnCount; i++)
                dt.Columns.Add(sheet.GetRow(0).GetCell(i).StringCellValue);

            //添加行,从索引为1的行开始
            int rowsCount = sheet.PhysicalNumberOfRows;
            for (int i = 1; i < rowsCount; i++)
            {
                DataRow dr = dt.NewRow();
                for (int j = 0; j < columnCount; j++)
                    dr.SetField(j, sheet.GetRow(i).GetCell(j).StringCellValue);
                dt.Rows.Add(dr);
            }
            ds.Tables.Add(dt);
        }
        return ds;
    }

    /// <summary>
    /// 将集合中的数据导入到excle中，不同的集合对应excel中的不同的工作表
    /// </summary>
    /// <param name="lists">不同对象的集合,集合中的对象可以通过设置特性来关联列名</param>
    /// <param name="fileName">保存的文件名，后缀名为.xls或.xlsx</param>
    public void ListToExcel(IList[] lists, string fileName)
    {
        DataSetToExcel(ConvertToDataSet(lists), fileName);
    }


    /// <summary>
    /// 将数据集中的数据导入到excel中，多个table对应的导入到excel对应多个工作表
    /// </summary>
    /// <param name="ds">要导出到excle中的数据集，数据集中表名和字段名在excel中对应工作表名和标题名称</param>
    /// <param name="fileName">保存的文件名，后缀名为.xls或.xlsx</param>
    public void DataSetToExcel(DataSet ds, string fileName)
    {
        if (ds != null)
        {
            IWorkbook wb = CreateSheet(fileName);
            foreach (DataTable dt in ds.Tables)
            {
                ImportToWorkbook(dt, ref wb);
            }

            downHelper.DownloadByOutputStreamBlock(
                new MemoryStream(ToByte(wb)), fileName);
        }
    }

    /// <summary>
    /// 将数据导入到excel中
    /// </summary>
    /// <param name="dt">要导出到excle中的数据表，表名和字段名在excel中对应工作表名和标题名称</param>
    /// <param name="fileName">保存的文件名，后缀名为.xls或.xlsx</param>
    public void DataTableToExcel(DataTable dt, string fileName)
    {
        IWorkbook wb = CreateSheet(fileName);
        ImportToWorkbook(dt, ref wb);
        downHelper.DownloadByOutputStreamBlock(
            new MemoryStream(ToByte(wb)), fileName);
    }


    private DataSet ConvertToDataSet(IList[] lists)
    {
        DataSet ds = new DataSet();

        foreach (IList list in lists)
        {
            if (list != null && list.Count > 0)
            {
                string tableName = list[0].GetType().Name;
                object[] classInfos = list[0].GetType().
                    GetCustomAttributes(typeof(EntityMappingAttribute), true);

                if (classInfos.Length > 0)
                    tableName = ((EntityMappingAttribute)classInfos[0]).Name;

                DataTable dt = new DataTable(tableName);
                object obj = list[0];
                PropertyInfo[] propertyInfos = obj.GetType().
                    GetProperties(BindingFlags.Public | BindingFlags.Instance);

                foreach (PropertyInfo propertyInfo in propertyInfos)
                {
                    object[] infos = propertyInfo.
                        GetCustomAttributes(typeof(EntityMappingAttribute), true);
                    if (infos.Length > 0)
                        dt.Columns.Add(((EntityMappingAttribute)infos[0]).Name);
                    else
                        dt.Columns.Add(propertyInfo.Name);
                }

                //添加数据
                for (int i = 0; i < list.Count; i++)
                {
                    DataRow dr = dt.NewRow();
                    object objTemp = list[i];
                    PropertyInfo[] propertyInfosTemp = objTemp.GetType().
                        GetProperties(BindingFlags.Public | BindingFlags.Instance);
                    for (int j = 0; j < propertyInfosTemp.Count(); j++)
                    {
                        dr.SetField(j, propertyInfosTemp[j].GetValue(obj, null));
                    }
                    dt.Rows.Add(dr);
                }

                ds.Tables.Add(dt);
            }
            else
            {
                ds.Tables.Add(new DataTable(list.GetType().Name));
            }
        }

        return ds;
    }


    private void ImportToWorkbook(DataTable dt, ref IWorkbook wb)
    {
        string sheetName = dt.TableName ?? "Sheet1";
        //创建工作表
        ISheet sheet = wb.CreateSheet(sheetName);
        //添加标题
        IRow titleRow = sheet.CreateRow(0);
        SetRow(titleRow,
            GetCloumnNames(dt),
            GetCellStyle(sheet.Workbook, FontBoldWeight.Bold));

        //添加数据行
        for (int i = 0; i < dt.Rows.Count; i++)
        {
            IRow dataRow = sheet.CreateRow(i + 1);
            SetRow(
                dataRow,
                GetRowValues(dt.Rows[i]),
                GetCellStyle(sheet.Workbook));
        }

        //设置表格自适应宽度
        AutoSizeColumn(sheet);
    }

    private byte[] ToByte(IWorkbook wb)
    {
        using (MemoryStream ms = new MemoryStream())
        {
            //XSSFWorkbook即读取.xlsx文件返回的MemoryStream是关闭
            //但是可以ToArray(),这是NPOI的bug
            wb.Write(ms);
            return ms.ToArray();
        }
    }

    private IWorkbook CreateSheet(string path)
    {
        IWorkbook wb = new NPOI.HSSF.UserModel.HSSFWorkbook(); ;
        string extension = System.IO.Path.GetExtension(path).ToLower();
        if (extension == ".xls")
            wb = new NPOI.HSSF.UserModel.HSSFWorkbook();
        else if (extension == ".xlsx")
            wb = new NPOI.XSSF.UserModel.XSSFWorkbook();

        return wb;
    }

    private int GetWidth(DataTable dt, int columnIndex)
    {
        IList<int> lengths = new List<int>();
        foreach (DataRow dr in dt.Rows)
            lengths.Add(Convert.ToString(dr[columnIndex]).Length * 256);
        return lengths.Max();
    }

    private IList<string> GetRowValues(DataRow dr)
    {
        List<string> rowValues = new List<string>();

        for (int i = 0; i < dr.Table.Columns.Count; i++)
            rowValues.Add(Convert.ToString(dr[i]));

        return rowValues;
    }

    private IList<string> GetCloumnNames(DataTable dt)
    {
        List<string> columnNames = new List<string>();

        foreach (DataColumn dc in dt.Columns)
            columnNames.Add(dc.ColumnName);

        return columnNames;
    }

    private void SetRow(IRow row, IList<string> values)
    {
        SetRow(row, values, null);
    }

    private void SetRow(IRow row, IList<string> values, ICellStyle cellStyle)
    {
        for (int i = 0; i < values.Count; i++)
        {
            ICell cell = row.CreateCell(i);
            cell.SetCellValue(values[i]);
            if (cellStyle != null)
                cell.CellStyle = cellStyle;
        }
    }

    private ICellStyle GetCellStyle(IWorkbook wb)
    {
        return GetCellStyle(wb, FontBoldWeight.None);
    }

    private ICellStyle GetCellStyle(IWorkbook wb, FontBoldWeight boldweight)
    {
        ICellStyle cellStyle = wb.CreateCellStyle();

        //字体样式
        IFont font = wb.CreateFont();
        font.FontHeightInPoints = 10;
        font.FontName = "微软雅黑";
        font.Color = (short)FontColor.Normal;
        font.Boldweight = (short)boldweight;

        cellStyle.SetFont(font);

        //对齐方式
        cellStyle.Alignment = HorizontalAlignment.Center;
        cellStyle.VerticalAlignment = VerticalAlignment.Center;

        //边框样式
        cellStyle.BorderTop = NPOI.SS.UserModel.BorderStyle.Thin;
        cellStyle.BorderBottom = NPOI.SS.UserModel.BorderStyle.Thin;
        cellStyle.BorderLeft = NPOI.SS.UserModel.BorderStyle.Thin;
        cellStyle.BorderRight = NPOI.SS.UserModel.BorderStyle.Thin;

        //设置背景色
        cellStyle.FillForegroundColor = NPOI.HSSF.Util.HSSFColor.White.Index;
        cellStyle.FillPattern = FillPattern.SolidForeground;


        //是否自动换行
        cellStyle.WrapText = false;

        //缩进
        cellStyle.Indention = 0;

        return cellStyle;
    }

    private void AutoSizeColumn(ISheet sheet)
    {
        //获取当前列的宽度，然后对比本列的长度，取最大值
        for (int columnNum = 0; columnNum <= sheet.PhysicalNumberOfRows; columnNum++)
            AutoSizeColumn(sheet, columnNum);
    }

    private void AutoSizeColumn(ISheet sheet, int columnNum)
    {
        int columnWidth = sheet.GetColumnWidth(columnNum) / 256;
        for (int rowNum = 1; rowNum <= sheet.LastRowNum; rowNum++)
        {
            IRow currentRow = sheet.GetRow(rowNum) == null ?
                sheet.CreateRow(rowNum) : sheet.GetRow(rowNum);
            if (currentRow.GetCell(columnNum) != null)
            {
                ICell currentCell = currentRow.GetCell(columnNum);
                int length = System.Text.Encoding.Default.GetBytes(currentCell.ToString()).Length;
                if (columnWidth < length)
                    columnWidth = length;
            }
        }
        sheet.SetColumnWidth(columnNum, columnWidth * 256);
    }
}

文件下载

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using System.IO;

/// <summary>
/// 文件下载有以下四种方式, 大文件下载的处理方法：将文件分块下载。
/// Response.OutputStream.Write
/// Response.TransmitFile
/// Response.WriteFile
/// Response.BinaryWrite
/// </summary>
public class DownHelper
{
    HttpResponse Response = null;
    public DownHelper()
    {
        Response = HttpContext.Current.Response;
    }

    public void DownloadByOutputStreamBlock(System.IO.Stream stream, string fileName)
    {
        using (stream)
        {
            //将流的位置设置到开始位置。
            stream.Position = 0;
            //块大小
            long ChunkSize = 102400;
            //建立100k的缓冲区
            byte[] buffer = new byte[ChunkSize];
            //已读字节数
            long dataLengthToRead = stream.Length;

            Response.ContentType = "application/octet-stream";
            Response.AddHeader("Content-Disposition",
                string.Format("attachment; filename={0}", HttpUtility.UrlPathEncode(fileName)));

            while (dataLengthToRead > 0 && Response.IsClientConnected)
            {
                int lengthRead = stream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小
                Response.OutputStream.Write(buffer, 0, lengthRead);
                Response.Flush();
                Response.Clear();
                dataLengthToRead -= lengthRead;
            }
            Response.Close();
        }
    }

    public void DownloadByTransmitFile(string filePath, string fielName)
    {
        FileInfo info = new FileInfo(filePath);
        long fileSize = info.Length;
        Response.Clear();
        Response.ContentType = "application/x-zip-compressed";
        Response.AddHeader("Content-Disposition",
            string.Format("attachment;filename={0}", HttpUtility.UrlPathEncode(fielName)));
        //不指明Content-Length用Flush的话不会显示下载进度  
        Response.AddHeader("Content-Length", fileSize.ToString());
        Response.TransmitFile(filePath, 0, fileSize);
        Response.Flush();
        Response.Close();
    }

    public void DownloadByWriteFile(string filePath, string fileName)
    {
        FileInfo info = new FileInfo(filePath);
        long fileSize = info.Length;
        Response.Clear();
        Response.ContentType = "application/octet-stream";
        Response.AddHeader("Content-Disposition",
            string.Format("attachment;filename={0}", HttpUtility.UrlPathEncode(fileName)));

        //指定文件大小  
        Response.AddHeader("Content-Length", fileSize.ToString());
        Response.WriteFile(filePath, 0, fileSize);
        Response.Flush();
        Response.Close();
    }

    public void DownloadByOutputStreamBlock(string filePath, string fileName)
    {
        using (FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
        {
            //指定块大小  
            long chunkSize = 102400;
            //建立一个100K的缓冲区  
            byte[] buffer = new byte[chunkSize];
            //已读的字节数  
            long dataToRead = stream.Length;

            //添加Http头  
            Response.ContentType = "application/octet-stream";
            Response.AddHeader("Content-Disposition",
                string.Format("attachment;filename={0}", HttpUtility.UrlPathEncode(fileName)));
            Response.AddHeader("Content-Length", dataToRead.ToString());

            while (dataToRead > 0 && Response.IsClientConnected)
            {
                int length = stream.Read(buffer, 0, Convert.ToInt32(chunkSize));
                Response.OutputStream.Write(buffer, 0, length);
                Response.Flush();
                Response.Clear();
                dataToRead -= length;
            }
            Response.Close();
        }
    }

    public void DownloadByBinary(string filePath, string fileName)
    {
        using (FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
        {
            //指定块大小  
            long chunkSize = 102400;
            //建立一个100K的缓冲区  
            byte[] bytes = new byte[chunkSize];
            //已读的字节数  
            long dataToRead = stream.Length;

            //添加Http头  
            Response.ContentType = "application/octet-stream";
            Response.AddHeader("Content-Disposition",
                string.Format("attachment;filename={0}", HttpUtility.UrlPathEncode(fileName)));

            Response.AddHeader("Content-Length", bytes.Length.ToString());
            Response.BinaryWrite(bytes);
            Response.Flush();
            Response.Close();
        }
    }

    public void DownloadByBinaryBlock(string filePath, string fileName)
    {
        using (FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
        {
            //指定块大小  
            long chunkSize = 102400;
            //建立一个100K的缓冲区  
            byte[] buffer = new byte[chunkSize];
            //已读的字节数  
            long dataToRead = stream.Length;

            //添加Http头  
            Response.ContentType = "application/octet-stream";
            Response.AddHeader("Content-Disposition",
                string.Format("attachment;filename={0}", HttpUtility.UrlPathEncode(fileName)));
            Response.AddHeader("Content-Length", dataToRead.ToString());

            while (dataToRead > 0 && Response.IsClientConnected)
            {
                int length = stream.Read(buffer, 0, Convert.ToInt32(chunkSize));
                Response.BinaryWrite(buffer);
                Response.Flush();
                Response.Clear();

                dataToRead -= length;
            }
            Response.Close();
        }
    }
}

自定义特性

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

[AttributeUsage(AttributeTargets.Property | AttributeTargets.Class)]
public class EntityMappingAttribute : Attribute
{
    public string Name { get; set; }
}