asp.net（NPOI）导入导出excel表

修改自柳永法 http://www.yongfa365.com/的类ExcelHelper

using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Text;
using System.Web;
using NPOI;
using NPOI.HSSF;
using NPOI.HSSF.UserModel;
using NPOI.HPSF;
using NPOI.SS;
using NPOI.Util;
using NPOI.SS.UserModel;
using NPOI.SS.Util;
 
 
 public class ExcelHelper
 {
 /// <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>
 /// <Author>逆水寒龙修改自柳永法 http://www.yongfa365.com/ 2012-07-19 15:32</Author>
 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>
 /// <Author>逆水寒龙修改自柳永法 2012-07-19 15:32</Author>
 public static MemoryStream Export(DataTable dtSource, string strHeaderText)
 {
 HSSFWorkbook workbook = new HSSFWorkbook();
 Sheet sheet = workbook.CreateSheet();
 
 #region 右击文件 属性信息
 {
 DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
 dsi.Company = "逆水寒龙";
 workbook.DocumentSummaryInformation = dsi;
 
 SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
 si.Author = "逆水寒龙"; //填加xls文件作者信息
 si.ApplicationName = "询盘信息"; //填加xls文件创建程序信息
 si.LastAuthor = "craneexporter"; //填加xls文件最后保存者信息
 si.Comments = "询盘信息表"; //填加xls文件作者信息
 si.Title = "inquiry info of craneexporter"; //填加xls文件标题信息
 si.Subject = "inquiry infolist";//填加文件主题信息
 si.CreateDateTime = DateTime.Now;
 si.RevNumber = "Beta V1.0";
 workbook.SummaryInformation = si;
 }
 #endregion
 
 CellStyle dateStyle = workbook.CreateCellStyle();
 DataFormat 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
 {
 Row headerRow = sheet.CreateRow(0);
 headerRow.HeightInPoints = 25;
 headerRow.CreateCell(0).SetCellValue(strHeaderText);
 
 CellStyle headStyle = workbook.CreateCellStyle();
 headStyle.Alignment = HorizontalAlignment.CENTER;
 Font font = workbook.CreateFont();
 font.FontHeightInPoints = 20;
 font.Boldweight = 700;
 headStyle.SetFont(font);
 
 headerRow.GetCell(0).CellStyle = headStyle;
 Region rg = new Region(0, 0, 0, dtSource.Columns.Count - 1);
 sheet.AddMergedRegion(Region.ConvertToCellRangeAddress(rg));
 //headerRow.Dispose();
 }
 #endregion
 
 
 #region 列头及样式
 {
 Row headerRow = sheet.CreateRow(1);
 
 
 CellStyle headStyle = workbook.CreateCellStyle();
 headStyle.Alignment = HorizontalAlignment.CENTER;
 Font 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
 Row dataRow = sheet.CreateRow(rowIndex);
 foreach (DataColumn column in dtSource.Columns)
 {
 Cell 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>
 /// <Author>柳永法 2010-5-8 22:21:41</Author>
 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);
 }
 Sheet sheet = hssfworkbook.GetSheetAt(0);
 System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
 
 Row headerRow = sheet.GetRow(0);
 int cellCount = headerRow.LastCellNum;
 
 for (int j = 0; j < cellCount; j++)
 {
 Cell cell = headerRow.GetCell(j);
 dt.Columns.Add(cell.ToString());
 }
 
 for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++)
 {
 Row 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;
 }
 
 }

下面就是调用了，调用指定的数据生成datetable

protected void Button1_Click(object sender, EventArgs e)
    {
        //string sql = "SELECT * FROM [sfzh].[dbo].[查询]";
        string sql = "select * from hh_inquiry order by inquiry_time desc;";
        DataTable dt = DbHelperSQL.Query(sql).Tables[0];
        //OutExcel oe = new OutExcel();
        //oe.initdata(this, DateTime.Now.ToString()+".xls", dt, "询盘信息表");
        ExcelHelper.ExportByWeb(dt, "询盘信息表","询盘信息表.xls");
        dt.Dispose();
    }

　　通过修改呢，有进一步了解了npoi的强悍，错，是彪悍，自我感觉通过看源代码学会了不少东西，也觉得深有感触，看比较规范的代码很爽的。大家都知道^_^

本文所用的dll在这里下载