.Net操作Excel

先去官网：http://npoi.codeplex.com/下载需要引入dll（可以选择.net2.0或者.net4.0的dll），然后在网站中添加引用。

.Net导出代码：

  /// <summary>
     /// 导出
     /// </summary>
     /// <param name="sender"></param>
     /// <param name="e"></param>
     protected void But_Excel_Click(object sender, EventArgs e)
     {
         string[] fileName = { "State_title", "Last_url", "State_url", "IsNewUser", "State_time", "IpAddress", "ExtStr1", "ExtStr2", "VisitTime", "VisitWay", "KeyWords", "UserAction", "Remark" };
         string[] title = { "受访网页", "来源网页", "受访网页URL", "新老访客", "访问时长", "IP地址", "地域", "访客标识码", "访问时间", "浏览方式", "关键字", "用户行为", "备注" };
         DataToExcel.ExportSiteState(fileName, title, "tb_SiteStats", "列表_" + DateTime.Now.ToString("yyy-MM-dd"), strWhere, " VisitTime desc ");
     }

 /// <summary>
         /// add by lwf 2016-07-13 16:22:19
         /// </summary>
         /// <param name="fileName"></param>
         /// <param name="title"></param>
         /// <param name="tableName"></param>
         /// <param name="sheetName"></param>
         /// <param name="strWhere"></param>
         /// <param name="sort"></param>
         public static void ExportSiteState(string[] fileName, string[] title, string tableName, string sheetName, string strWhere, string sort)
         {
             string sql = "select ";
             if (fileName == null || fileName.Length < )
             {
                 sql += "* ";
             }
             else
             {
                 foreach (string key in fileName)
                 {
                     sql += key + ",";
                 }
                 sql = System.Text.RegularExpressions.Regex.Replace(sql, ",$", " ");
             }
             sql += "from " + tableName;
             if (!string.IsNullOrEmpty(strWhere))
             {
                 sql += " where " + strWhere;
             }
             if (!string.IsNullOrEmpty(sort))
             {
                 sql += " order by " + sort;
             }

             //获取需要导出的数据
             DataTable dt = DbHelperSQLServer.Query(sql).Tables[];
             NPOI.HSSF.UserModel.HSSFWorkbook book = new NPOI.HSSF.UserModel.HSSFWorkbook();
             NPOI.SS.UserModel.Sheet sheet = book.CreateSheet(sheetName);
             NPOI.SS.UserModel.Row row = sheet.CreateRow();

             //设置列名称和数据
             if (title == null || title.Length < )
             {
                 for (int i = ; i < dt.Columns.Count; i++)
                 {
                     row.CreateCell(i).SetCellValue(dt.Columns[i].ColumnName);
                 }
                 for (int i = ; i < dt.Rows.Count; i++)
                 {
                     NPOI.SS.UserModel.Row row2 = sheet.CreateRow(i + );
                     for (int j = ; j < dt.Columns.Count; j++)
                         row2.CreateCell(j).SetCellValue(dt.Rows[i][j].ToString());
                 }
             }
             else
             {
                 for (int i = ; i < title.Length; i++)
                 {
                     row.CreateCell(i).SetCellValue(title[i].ToString());
                 }
                 for (int i = ; i < dt.Rows.Count; i++)
                 {
                     NPOI.SS.UserModel.Row row2 = sheet.CreateRow(i + );
                     for (int j = ; j < fileName.Length; j++)
                         row2.CreateCell(j).SetCellValue(dt.Rows[i][fileName[j]].ToString());
                 }
             }
             //写入到客户端
             System.IO.MemoryStream ms = new System.IO.MemoryStream();
             book.Write(ms);
             System.Web.HttpContext.Current.Response.AddHeader("Content-Disposition", string.Format("attachment; filename=Export_" + DateTime.Now.ToString("yyyy-MM-dd") + ".xls"));
             System.Web.HttpContext.Current.Response.BinaryWrite(ms.ToArray());
             book = null;
             ms.Close();
             ms.Dispose();
         }

DataTable转换成Excel文档流(导出数据量超出65535条,分sheet)：

 using System;
 using System.Collections.Generic;
 using System.Text;
 using Maticsoft.DBUtility;
 using System.Collections;
 using System.Data;
 using System.Web;
 using DAL;
 using NPOI.HSSF.UserModel;
 using System.IO;
 using NPOI.SS.UserModel;
 namespace DAL
 {
    public class DataToExcel
     {/// <summary>
      /// DataTable转换成Excel文档流，并输出到客户端
      /// </summary>
      /// <param name="table"></param>
      /// <param name="response"></param>
      /// <param name="fileName">输出的文件名</param>
         public static void RenderToDataTableToExcel(DataTable table,HttpContext context, string fileName)
         {
             using (MemoryStream ms = ExportDataTableToExcel(table))
             {
                 RenderToBrowser(ms, context, fileName);
             }
         }

         /// <summary>
         /// DataTable转换成Excel文档流(导出数据量超出65535条,分sheet)
         /// </summary>
         /// <param name="table"></param>
         /// <returns></returns>
         public static MemoryStream ExportDataTableToExcel(DataTable sourceTable)
         {
             HSSFWorkbook workbook = new HSSFWorkbook();
             MemoryStream ms = new MemoryStream();
             int dtRowsCount = sourceTable.Rows.Count;
             int SheetCount = Convert.ToInt32(Math.Ceiling(Convert.ToDouble(dtRowsCount) / ));
             int SheetNum = ;
             int rowIndex = ;
             int tempIndex = ; //标示
             ISheet sheet = workbook.CreateSheet("sheet1" + SheetNum);
             for (int i = ; i < dtRowsCount; i++)
             {
                 if (i ==  || tempIndex == )
                 {
                     IRow headerRow = sheet.CreateRow();
                     foreach (DataColumn column in sourceTable.Columns)
                         headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
                 }
                 HSSFRow dataRow = (HSSFRow)sheet.CreateRow(tempIndex);
                 foreach (DataColumn column in sourceTable.Columns)
                 {
                     dataRow.CreateCell(column.Ordinal).SetCellValue(sourceTable.Rows[i][column].ToString());
                 }
                 if (tempIndex == )
                 {
                     SheetNum++;
                     sheet = workbook.CreateSheet("sheet" + SheetNum);//
                     tempIndex = ;
                 }
                 rowIndex++;
                 tempIndex++;
                 //AutoSizeColumns(sheet);
             }
             workbook.Write(ms);
             ms.Flush();
             ms.Position = ;
             sheet = null;
             // headerRow = null;
             workbook = null;
             return ms;
         }

         /// <summary>
         /// 输出文件到浏览器
         /// </summary>
         /// <param name="ms">Excel文档流</param>
         /// <param name="context">HTTP上下文</param>
         /// <param name="fileName">文件名</param>
         private static void RenderToBrowser(MemoryStream ms, HttpContext context, string fileName)
         {
             if (context.Request.Browser.Browser == "IE")
                 fileName = HttpUtility.UrlEncode(fileName);
             context.Response.AddHeader("Content-Disposition", "attachment;fileName=" + fileName);
             context.Response.BinaryWrite(ms.ToArray());
         }
     }
 }

.NET导入代码：

 HSSFWorkbook hssfworkbook;
 #region
 public DataTable ImportExcelFile(string filePath)
 {
     #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.Sheet sheet = hssfworkbook.GetSheetAt();
     System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
     DataTable dt = new DataTable();
     for (int j = ; j < (sheet.GetRow().LastCellNum); j++)
     {
         dt.Columns.Add(Convert.ToChar(((int)'A') + j).ToString());
     }
     while (rows.MoveNext())
     {
         HSSFRow row = (HSSFRow)rows.Current;
         DataRow dr = dt.NewRow();
         for (int i = ; i < row.LastCellNum; i++)
         {
             NPOI.SS.UserModel.Cell cell = row.GetCell(i);
             if (cell == null)
             {
                 dr[i] = null;
             }
             else
             {
                 dr[i] = cell.ToString();
             }
         }
         dt.Rows.Add(dr);
     }
     return dt;
 }
 #endregion  

NPOIbinary2.1.3.1.zip下载