C#讀取Excel 幾種方法的體會

(1) OleDb： 用這種方法讀取Excel速度還是非常的快的，但這種方式讀取數據的時候不太靈活，不過可以在 DataTable 中對數據進行一些刪減修改

這種方式將Excel作為一個數據源，直接用Sql語句獲取數據了。所以讀取之前要知道此次要讀取的Sheet（當然也可以用序號，類似dt.Row[0][0]。這樣倒是不需要知道Sheet）

if (fileType == ".xls")
   connStr = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + fileName + ";" + ";Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1\"";
else
   connStr = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=" + fileName + ";" + ";Extended Properties=\"Excel 12.0;HDR=YES;IMEX=1\"";

OleDbConnection conn new OleDbConnection(connStr);
DataTable dtSheetName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });

以上是讀取Excel的Sheet名，xls和xlsx的連接字符串也不一樣的，可以根據文件的后綴來區別。這里需要注意的一點，Excel里面只有一個Sheet，但通過這種方式讀取Sheet可能會大於一個。原因已經有人在別的網站說過了，偷一下懶O(∩_∩)O，下面文段來自【cdwolfling】

【在使用過程中發現取出的Sheet和實際excel不一致， 會多出不少。目前總結后有兩種情況：

1. 取出的名稱中，包括了XL命名管理器中的名稱（參見XL2007的公式--命名管理器， 快捷鍵Crtl+F3）；

2. 取出的名稱中，包括了FilterDatabase后綴的， 這是XL用來記錄Filter范圍的， 參見http://www.mrexcel.com/forum/showthread.php?t=27225；

對於第一點比較簡單， 刪除已有命名管理器中的內容即可；第二點處理起來比較麻煩， Filter刪除后這些名稱依然保留着，簡單的做法是新增sheet然后將原sheet Copy進去】

---------------------------------

但實際情況並不能為每個Excel做以上檢查，【cdwolfling】也給出了過濾的方案，當時還是有點問題，本來補充了一點。總之先看代碼吧

for (int i = 0; i < dtSheetName.Rows.Count; i++)

{

SheetName = (string)dtSheetName.Rows[i]["TABLE_NAME"];

if (SheetName .Contains("$") && !SheetName .Replace("'", "").EndsWith("$"))continue;//過濾無效SheetName完畢....

da.SelectCommand = new OleDbCommand(String.Format(sql_F, tblName), conn);
DataSet dsItem = new DataSet();
da.Fill(dsItem, tblName);

}

因為讀取出來無效SheetName一般情況最后一個字符都不會是$。如果SheetName有一些特殊符號，讀取出來的SheetName會自動加上單引號，比如在Excel中將SheetName編輯成：MySheet(1)，此時讀取出來的SheetName就為：'MySheet(1)$'，所以判斷最后一個字符是不是$之前最好過濾一下單引號。

優點：讀取方式簡單、讀取速度快

缺點：除了讀取過程不太靈活之外，這種讀取方式還有個弊端就是，當Excel數據量很大時。會非常占用內存，當內存不夠時會拋出內存溢出的異常。

不過一般情況下還是非常不錯的

 讀取Excel完整代碼：

/// <summary>
        /// 讀取Excel文件到DataSet中
        /// </summary>
        /// <param name="filePath">文件路徑</param>
        /// <returns></returns>
        public static DataSet ToDataTable(string filePath)
        {
            string connStr = "";            
            string fileType = System.IO.Path.GetExtension(fileName);
            if (string.IsNullOrEmpty(fileType)) return null;

            if (fileType == ".xls")
                connStr = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + filePath+ ";" + ";Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1\"";
            else
                connStr = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=" + filePath+ ";" + ";Extended Properties=\"Excel 12.0;HDR=YES;IMEX=1\"";
            string sql_F = "Select * FROM [{0}]";

            OleDbConnection conn = null;
            OleDbDataAdapter da = null;
            DataTable dtSheetName= null;

            DataSet ds = new DataSet();
            try
            {
                // 初始化連接，並打開
                conn = new OleDbConnection(connStr);
                conn.Open();

                // 獲取數據源的表定義元數據                        
                string SheetName = "";
                dtSheetName= conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });

                // 初始化適配器
                da = new OleDbDataAdapter();
                for (int i = 0; i < dtSheetName.Rows.Count; i++)
                {
                    SheetName = (string)dtSheetName.Rows[i]["TABLE_NAME"];

                    if (SheetName .Contains("$") && !SheetName .Replace("'", "").EndsWith("$"))
                    {
                        continue;
                    }

                    da.SelectCommand = new OleDbCommand(String.Format(sql_F, SheetName ), conn);
                    DataSet dsItem = new DataSet();
                    da.Fill(dsItem, tblName);

                    ds.Tables.Add(dsItem.Tables[0].Copy());
                }
            }
            catch (Exception ex)
            {
            }
            finally
            {
                // 關閉連接
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                    da.Dispose();
                    conn.Dispose();
                }
            }
            return ds;
        }

　　

(2)：Com組件的方式讀取Excel

這種方式需要先引用 Microsoft.Office.Interop.Excel 。首選說下這種方式的優缺點

優點：可以非常靈活的讀取Excel中的數據

缺點：如果是Web站點部署在IIS上時，還需要服務器機子已安裝了Excel，有時候還需要為配置IIS權限。最重要的一點因為是基於單元格方式讀取的，所以數據很慢（曾做過試驗，直接讀取千行、200多列的文件，直接讀取耗時15分鍾。即使采用多線程分段讀取來提高CPU的利用率也需要8分鍾。PS：CPU I3）

需要讀取大文件的的童鞋們慎重。。。

附上單線程和多線程讀取類：

public class ExcelOptions
    {
        private Stopwatch wath = new Stopwatch();

        /// <summary>
        /// 使用COM讀取Excel
        /// </summary>
        /// <param name="excelFilePath">路徑</param>
        /// <returns>DataTabel</returns>
        public System.Data.DataTable GetExcelData(string excelFilePath)
        {
            Excel.Application app = new Excel.Application();
            Excel.Sheets sheets;
            Excel.Workbook workbook = null;
            object oMissiong = System.Reflection.Missing.Value;
            System.Data.DataTable dt = new System.Data.DataTable();

            wath.Start();

            try
            {
                if (app == null)
                {
                    return null;
                }

                workbook = app.Workbooks.Open(excelFilePath, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong);

                //將數據讀入到DataTable中——Start   

                sheets = workbook.Worksheets;
                Excel.Worksheet worksheet = (Excel.Worksheet)sheets.get_Item(1);//讀取第一張表
                if (worksheet == null)
                    return null;

                string cellContent;
                int iRowCount = worksheet.UsedRange.Rows.Count;
                int iColCount = worksheet.UsedRange.Columns.Count;
                Excel.Range range;

                //負責列頭Start
                DataColumn dc;
                int ColumnID = 1;
                range = (Excel.Range)worksheet.Cells[1, 1];
                while (range.Text.ToString().Trim() != "")
                {
                    dc = new DataColumn();
                    dc.DataType = System.Type.GetType("System.String");
                    dc.ColumnName = range.Text.ToString().Trim();
                    dt.Columns.Add(dc);

                    range = (Excel.Range)worksheet.Cells[1, ++ColumnID];
                }
                //End

                for (int iRow = 2; iRow <= iRowCount; iRow++)
                {
                    DataRow dr = dt.NewRow();

                    for (int iCol = 1; iCol <= iColCount; iCol++)
                    {
                        range = (Excel.Range)worksheet.Cells[iRow, iCol];

                        cellContent = (range.Value2 == null) ? "" : range.Text.ToString();

                        //if (iRow == 1)
                        //{
                        //    dt.Columns.Add(cellContent);
                        //}
                        //else
                        //{
                            dr[iCol - 1] = cellContent;
                        //}
                    }

                    //if (iRow != 1)
                    dt.Rows.Add(dr);
                }

                wath.Stop();
                TimeSpan ts = wath.Elapsed;

                //將數據讀入到DataTable中——End
                return dt;
            }
            catch
            {
                
                return null;
            }
            finally 
            {
                workbook.Close(false, oMissiong, oMissiong);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
                workbook = null;
                app.Workbooks.Close();
                app.Quit();
                System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
                app = null;
                GC.Collect();
                GC.WaitForPendingFinalizers();
            }
        }


        /// <summary>
        /// 使用COM，多線程讀取Excel（1 主線程、4 副線程）
        /// </summary>
        /// <param name="excelFilePath">路徑</param>
        /// <returns>DataTabel</returns>
        public System.Data.DataTable ThreadReadExcel(string excelFilePath)
        {
            Excel.Application app = new Excel.Application();
            Excel.Sheets sheets = null;
            Excel.Workbook workbook = null;
            object oMissiong = System.Reflection.Missing.Value;
            System.Data.DataTable dt = new System.Data.DataTable();

            wath.Start();

            try
            {
                if (app == null)
                {
                    return null;
                }

                workbook = app.Workbooks.Open(excelFilePath, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong);

                //將數據讀入到DataTable中——Start   
                sheets = workbook.Worksheets;
                Excel.Worksheet worksheet = (Excel.Worksheet)sheets.get_Item(1);//讀取第一張表
                if (worksheet == null)
                    return null;

                string cellContent;
                int iRowCount = worksheet.UsedRange.Rows.Count;
                int iColCount = worksheet.UsedRange.Columns.Count;
                Excel.Range range;

                //負責列頭Start
                DataColumn dc;
                int ColumnID = 1;
                range = (Excel.Range)worksheet.Cells[1, 1];
                //while (range.Text.ToString().Trim() != "")
                while (iColCount >= ColumnID)
                {
                    dc = new DataColumn();
                    dc.DataType = System.Type.GetType("System.String");

                    string strNewColumnName = range.Text.ToString().Trim();
                    if (strNewColumnName.Length == 0) strNewColumnName = "_1";
                    //判斷列名是否重復
                    for (int i = 1; i < ColumnID; i++)
                    {
                        if (dt.Columns[i - 1].ColumnName == strNewColumnName)
                            strNewColumnName = strNewColumnName + "_1";
                    }

                    dc.ColumnName = strNewColumnName;
                    dt.Columns.Add(dc);

                    range = (Excel.Range)worksheet.Cells[1, ++ColumnID];
                }
                //End

                //數據大於500條，使用多進程進行讀取數據
                if (iRowCount - 1 > 500)
                {
                    //開始多線程讀取數據
                    //新建線程
                    int b2 = (iRowCount - 1) / 10;
                    DataTable dt1 = new DataTable("dt1");
                    dt1 = dt.Clone();
                    SheetOptions sheet1thread = new SheetOptions(worksheet, iColCount, 2, b2 + 1, dt1);
                    Thread othread1 = new Thread(new ThreadStart(sheet1thread.SheetToDataTable));
                    othread1.Start();

                    //阻塞 1 毫秒，保證第一個讀取 dt1
                    Thread.Sleep(1);

                    DataTable dt2 = new DataTable("dt2");
                    dt2 = dt.Clone();
                    SheetOptions sheet2thread = new SheetOptions(worksheet, iColCount, b2 + 2, b2 * 2 + 1, dt2);
                    Thread othread2 = new Thread(new ThreadStart(sheet2thread.SheetToDataTable));
                    othread2.Start();

                    DataTable dt3 = new DataTable("dt3");
                    dt3 = dt.Clone();
                    SheetOptions sheet3thread = new SheetOptions(worksheet, iColCount, b2 * 2 + 2, b2 * 3 + 1, dt3);
                    Thread othread3 = new Thread(new ThreadStart(sheet3thread.SheetToDataTable));
                    othread3.Start();

                    DataTable dt4 = new DataTable("dt4");
                    dt4 = dt.Clone();
                    SheetOptions sheet4thread = new SheetOptions(worksheet, iColCount, b2 * 3 + 2, b2 * 4 + 1, dt4);
                    Thread othread4 = new Thread(new ThreadStart(sheet4thread.SheetToDataTable));
                    othread4.Start();

                    //主線程讀取剩余數據
                    for (int iRow = b2 * 4 + 2; iRow <= iRowCount; iRow++)
                    {
                        DataRow dr = dt.NewRow();
                        for (int iCol = 1; iCol <= iColCount; iCol++)
                        {
                            range = (Excel.Range)worksheet.Cells[iRow, iCol];
                            cellContent = (range.Value2 == null) ? "" : range.Text.ToString();
                            dr[iCol - 1] = cellContent;
                        }
                        dt.Rows.Add(dr);
                    }

                    othread1.Join();
                    othread2.Join();
                    othread3.Join();
                    othread4.Join();

                    //將多個線程讀取出來的數據追加至 dt1 后面
                    foreach (DataRow dr in dt.Rows)
                        dt1.Rows.Add(dr.ItemArray);
                    dt.Clear();
                    dt.Dispose();

                    foreach (DataRow dr in dt2.Rows)
                        dt1.Rows.Add(dr.ItemArray);
                    dt2.Clear();
                    dt2.Dispose();

                    foreach (DataRow dr in dt3.Rows)
                        dt1.Rows.Add(dr.ItemArray);
                    dt3.Clear();
                    dt3.Dispose();

                    foreach (DataRow dr in dt4.Rows)
                        dt1.Rows.Add(dr.ItemArray);
                    dt4.Clear();
                    dt4.Dispose();

                    return dt1;
                }
                else
                {
                    for (int iRow = 2; iRow <= iRowCount; iRow++)
                    {
                        DataRow dr = dt.NewRow();
                        for (int iCol = 1; iCol <= iColCount; iCol++)
                        {
                            range = (Excel.Range)worksheet.Cells[iRow, iCol];
                            cellContent = (range.Value2 == null) ? "" : range.Text.ToString();
                            dr[iCol - 1] = cellContent;
                        }
                        dt.Rows.Add(dr);
                    }
                }

                wath.Stop();
                TimeSpan ts = wath.Elapsed;
                //將數據讀入到DataTable中——End
                return dt;
            }
            catch
            {

                return null;
            }
            finally
            {
                workbook.Close(false, oMissiong, oMissiong);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(sheets);
                workbook = null;
                app.Workbooks.Close();
                app.Quit();
                System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
                app = null;
                GC.Collect();
                GC.WaitForPendingFinalizers();
                
                /*
                object objmissing = System.Reflection.Missing.Value;

Excel.ApplicationClass application = new ApplicationClass();
Excel.Workbook book = application.Workbooks.Add(objmissing);
Excel.Worksheet sheet = (Excel.Worksheet)book.Worksheets.Add（objmissing,objmissing,objmissing,objmissing);

//操作過程 ^&%&×&……&%&&……

//釋放
sheet.SaveAs(path,objmissing,objmissing,objmissing,objmissing,objmissing,objmissing,objmissing,objmissing);
System.Runtime.InteropServices.Marshal.ReleaseComObject((object)sheet);
System.Runtime.InteropServices.Marshal.ReleaseComObject((object)book);
application.Quit();
System.Runtime.InteropServices.Marshal.ReleaseComObject((object)application);
System.GC.Collect();
                 */
            }
        }


        /// <summary>
        /// 刪除Excel行
        /// </summary>
        /// <param name="excelFilePath">Excel路徑</param>
        /// <param name="rowStart">開始行</param>
        /// <param name="rowEnd">結束行</param>
        /// <param name="designationRow">指定行</param>
        /// <returns></returns>
        public string DeleteRows(string excelFilePath, int rowStart, int rowEnd, int designationRow)
        {
            string result = "";
            Excel.Application app = new Excel.Application();
            Excel.Sheets sheets;
            Excel.Workbook workbook = null;
            object oMissiong = System.Reflection.Missing.Value;
            try
            {
                if (app == null)
                {
                    return "分段讀取Excel失敗";
                }

                workbook = app.Workbooks.Open(excelFilePath, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong);
                sheets = workbook.Worksheets;
                Excel.Worksheet worksheet = (Excel.Worksheet)sheets.get_Item(1);//讀取第一張表
                if (worksheet == null)
                    return result;
                Excel.Range range;

                //先刪除指定行，一般為列描述
                if (designationRow != -1)
                {
                    range = (Excel.Range)worksheet.Rows[designationRow, oMissiong];
                    range.Delete(Excel.XlDeleteShiftDirection.xlShiftUp);
                }
                Stopwatch sw = new Stopwatch();
                sw.Start();

                int i = rowStart;
                for (int iRow = rowStart; iRow <= rowEnd; iRow++, i++)
                {
                    range = (Excel.Range)worksheet.Rows[rowStart, oMissiong];
                    range.Delete(Excel.XlDeleteShiftDirection.xlShiftUp);
                }

                sw.Stop();
                TimeSpan ts = sw.Elapsed;
                workbook.Save();

                //將數據讀入到DataTable中——End
                return result;
            }
            catch
            {

                return "分段讀取Excel失敗";
            }
            finally
            {
                workbook.Close(false, oMissiong, oMissiong);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook);
                workbook = null;
                app.Workbooks.Close();
                app.Quit();
                System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
                app = null;
                GC.Collect();
                GC.WaitForPendingFinalizers();
            }
        }

        public void ToExcelSheet(DataSet ds, string fileName)
        {
            Excel.Application appExcel = new Excel.Application();
            Excel.Workbook workbookData = null;
            Excel.Worksheet worksheetData;
            Excel.Range range;
            try
            {
                workbookData = appExcel.Workbooks.Add(System.Reflection.Missing.Value);
                appExcel.DisplayAlerts = false;//不顯示警告
                //xlApp.Visible = true;//excel是否可見
                //
                //for (int i = workbookData.Worksheets.Count; i > 0; i--)
                //{
                //    Microsoft.Office.Interop.Excel.Worksheet oWorksheet = (Microsoft.Office.Interop.Excel.Worksheet)workbookData.Worksheets.get_Item(i);
                //    oWorksheet.Select();
                //    oWorksheet.Delete();
                //}

                for (int k = 0; k < ds.Tables.Count; k++)
                {
                    worksheetData = (Excel.Worksheet)workbookData.Worksheets.Add(System.Reflection.Missing.Value, System.Reflection.Missing.Value, System.Reflection.Missing.Value, System.Reflection.Missing.Value);
                    // testnum--;
                    if (ds.Tables[k] != null)
                    {
                        worksheetData.Name = ds.Tables[k].TableName;
                        //寫入標題
                        for (int i = 0; i < ds.Tables[k].Columns.Count; i++)
                        {
                            worksheetData.Cells[1, i + 1] = ds.Tables[k].Columns[i].ColumnName;
                            range = (Excel.Range)worksheetData.Cells[1, i + 1];
                            //range.Interior.ColorIndex = 15;
                            range.Font.Bold = true;
                            range.NumberFormatLocal = "@";//文本格式 
                            range.EntireColumn.AutoFit();//自動調整列寬 
                            // range.WrapText = true; //文本自動換行   
                            range.ColumnWidth = 15;
                        }
                        //寫入數值
                        for (int r = 0; r < ds.Tables[k].Rows.Count; r++)
                        {
                            for (int i = 0; i < ds.Tables[k].Columns.Count; i++)
                            {
                                worksheetData.Cells[r + 2, i + 1] = ds.Tables[k].Rows[r][i];
                                //Range myrange = worksheetData.get_Range(worksheetData.Cells[r + 2, i + 1], worksheetData.Cells[r + 3, i + 2]);
                                //myrange.NumberFormatLocal = "@";//文本格式 
                                //// myrange.EntireColumn.AutoFit();//自動調整列寬 
                                ////   myrange.WrapText = true; //文本自動換行   
                                //myrange.ColumnWidth = 15;
                            }
                            //  rowRead++;
                            //System.Windows.Forms.Application.DoEvents();
                        }
                    }
                    worksheetData.Columns.EntireColumn.AutoFit();
                    workbookData.Saved = true;
                }
            }
            catch (Exception ex) { }
            finally
            {
                workbookData.SaveCopyAs(fileName);
                workbookData.Close(false, System.Reflection.Missing.Value, System.Reflection.Missing.Value);
                appExcel.Quit();
                GC.Collect();
            }
        }
    
    }

　　

(3)NPOI方式讀取Excel，NPOI是一組開源的組件，類似Java的 POI。包括：NPOI、NPOI.HPSF、NPOI.HSSF、NPOI.HSSF.UserModel、NPOI.POIFS、NPOI.Util，下載的時候別只下一個噢

 

優點：讀取Excel速度較快，讀取方式操作靈活性

缺點：只支持03的Excel，xlsx的無法讀取。由於這點，使用這種方式的人不多啊，沒理由要求客戶使用03版Excel吧，再說03版Excel對於行數還有限制，只支持65536行。

（聽他們的開發人員說會在2012年底推出新版，支持xlsx的讀取。但一直很忙沒時間去關注這個事情，有興趣的同學可以瞧瞧去）

NPOI讀取Excel類：

using System;
using System.Data;
using System.IO;
using System.Web;
using NPOI;
using NPOI.HPSF;
using NPOI.HSSF;
using NPOI.HSSF.UserModel;
using NPOI.POIFS;
using NPOI.Util;
using System.Text;
using System.Configuration;

public class NPOIHelper
{
    private static int ExcelMaxRow = Convert.ToInt32(ConfigurationManager.AppSettings["ExcelMaxRow"]);
    /// <summary>
    /// 由DataSet導出Excel
    /// </summary>
    /// <param name="sourceTable">要導出數據的DataTable</param>    
    /// <param name="sheetName">工作表名稱</param>
    /// <returns>Excel工作表</returns>    
    private static Stream ExportDataSetToExcel(DataSet sourceDs)
    {
        HSSFWorkbook workbook = new HSSFWorkbook();
        MemoryStream ms = new MemoryStream();

        for (int i = 0; i < sourceDs.Tables.Count; i++)
        {
            HSSFSheet sheet = (HSSFSheet)workbook.CreateSheet(sourceDs.Tables[i].TableName);
            HSSFRow headerRow = (HSSFRow)sheet.CreateRow(0);
            // handling header.            
            foreach (DataColumn column in sourceDs.Tables[i].Columns)
                headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
            // handling value.            
            int rowIndex = 1;
            foreach (DataRow row in sourceDs.Tables[i].Rows)
            {
                HSSFRow dataRow = (HSSFRow)sheet.CreateRow(rowIndex);
                foreach (DataColumn column in sourceDs.Tables[i].Columns)
                {
                    dataRow.CreateCell(column.Ordinal).SetCellValue(row[column].ToString());
                }
                rowIndex++;
            }
        }
        workbook.Write(ms);
        ms.Flush();
        ms.Position = 0;
        workbook = null;
        return ms;
    }
    /// <summary>
    /// 由DataSet導出Excel
    /// </summary>   
    /// <param name="sourceTable">要導出數據的DataTable</param>
    /// <param name="fileName">指定Excel工作表名稱</param>
    /// <returns>Excel工作表</returns>    
    public static void ExportDataSetToExcel(DataSet sourceDs, string fileName)
    {
        //檢查是否有Table數量超過65325
        for (int t = 0; t < sourceDs.Tables.Count; t++)
        {
            if (sourceDs.Tables[t].Rows.Count > ExcelMaxRow)
            {
                DataSet ds = GetdtGroup(sourceDs.Tables[t].Copy());
                sourceDs.Tables.RemoveAt(t);
                //將得到的ds插入 sourceDs中
                for (int g = 0; g < ds.Tables.Count; g++)
                {
                    DataTable dt = ds.Tables[g].Copy();
                    sourceDs.Tables.Add(dt);
                }
                t--;
            }
        }

        MemoryStream ms = ExportDataSetToExcel(sourceDs) as MemoryStream;
        HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + fileName);
        HttpContext.Current.Response.BinaryWrite(ms.ToArray());
        HttpContext.Current.ApplicationInstance.CompleteRequest();
        //HttpContext.Current.Response.End();
        ms.Close();
        ms = null;
    }
    /// <summary>
    /// 由DataTable導出Excel
    /// </summary>
    /// <param name="sourceTable">要導出數據的DataTable</param> 
    /// <returns>Excel工作表</returns>    
    private static Stream ExportDataTableToExcel(DataTable sourceTable)
    {
        HSSFWorkbook workbook = new HSSFWorkbook();
        MemoryStream ms = new MemoryStream();
        HSSFSheet sheet = (HSSFSheet)workbook.CreateSheet(sourceTable.TableName);
        HSSFRow headerRow = (HSSFRow)sheet.CreateRow(0);
        // handling header.      
        foreach (DataColumn column in sourceTable.Columns)
            headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
        // handling value.      
        int rowIndex = 1;
        foreach (DataRow row in sourceTable.Rows)
        {
            HSSFRow dataRow = (HSSFRow)sheet.CreateRow(rowIndex);
            foreach (DataColumn column in sourceTable.Columns)
            {
                dataRow.CreateCell(column.Ordinal).SetCellValue(row[column].ToString());
            }
            rowIndex++;
        }
        workbook.Write(ms);
        ms.Flush();
        ms.Position = 0;
        sheet = null;
        headerRow = null;
        workbook = null;
        return ms;
    }
    /// <summary>
    /// 由DataTable導出Excel
    /// </summary>
    /// <param name="sourceTable">要導出數據的DataTable</param>
    /// <param name="fileName">指定Excel工作表名稱</param>
    /// <returns>Excel工作表</returns>
    public static void ExportDataTableToExcel(DataTable sourceTable, string fileName)
    {
        //如數據超過65325則分成多個Table導出
        if (sourceTable.Rows.Count > ExcelMaxRow)
        {
            DataSet ds = GetdtGroup(sourceTable);
            //導出DataSet
            ExportDataSetToExcel(ds, fileName);
        }
        else
        {
            MemoryStream ms = ExportDataTableToExcel(sourceTable) as MemoryStream;
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + fileName);
            HttpContext.Current.Response.BinaryWrite(ms.ToArray());
            HttpContext.Current.ApplicationInstance.CompleteRequest();
            //HttpContext.Current.Response.End();
            ms.Close();
            ms = null;
        }
    }

    /// <summary>
    /// 傳入行數超過65325的Table，返回DataSet
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public static DataSet GetdtGroup(DataTable dt)
    {
        string tablename = dt.TableName;

        DataSet ds = new DataSet();
        ds.Tables.Add(dt);

        double n = dt.Rows.Count / Convert.ToDouble(ExcelMaxRow);

        //創建表
        for (int i = 1; i < n; i++)
        {
            DataTable dtAdd = dt.Clone();
            dtAdd.TableName = tablename + "_" + i.ToString();
            ds.Tables.Add(dtAdd);
        }

        //分解數據
        for (int i = 1; i < ds.Tables.Count; i++)
        {
            //新表行數達到最大 或 基表數量不足
            while (ds.Tables[i].Rows.Count != ExcelMaxRow && ds.Tables[0].Rows.Count != ExcelMaxRow)
            {
                ds.Tables[i].Rows.Add(ds.Tables[0].Rows[ExcelMaxRow].ItemArray);
                ds.Tables[0].Rows.RemoveAt(ExcelMaxRow);

            }
        }

        return ds;
    }

    /// <summary>
    /// 由DataTable導出Excel
    /// </summary>
    /// <param name="sourceTable">要導出數據的DataTable</param>
    /// <param name="fileName">指定Excel工作表名稱</param>
    /// <returns>Excel工作表</returns>
    public static void ExportDataTableToExcelModel(DataTable sourceTable, string modelpath, string modelName, string fileName, string sheetName)
    {
        int rowIndex = 2;//從第二行開始，因為前兩行是模板里面的內容 
        int colIndex = 0;
        FileStream file = new FileStream(modelpath + modelName + ".xls", FileMode.Open, FileAccess.Read);//讀入excel模板
        HSSFWorkbook hssfworkbook = new HSSFWorkbook(file);
        HSSFSheet sheet1 = (HSSFSheet)hssfworkbook.GetSheet("Sheet1");
        sheet1.GetRow(0).GetCell(0).SetCellValue("excelTitle");      //設置表頭
        foreach (DataRow row in sourceTable.Rows)
        {   //雙循環寫入sourceTable中的數據
            rowIndex++;
            colIndex = 0;
            HSSFRow xlsrow = (HSSFRow)sheet1.CreateRow(rowIndex);
            foreach (DataColumn col in sourceTable.Columns)
            {
                xlsrow.CreateCell(colIndex).SetCellValue(row[col.ColumnName].ToString());
                colIndex++;
            }
        }
        sheet1.ForceFormulaRecalculation = true;
        FileStream fileS = new FileStream(modelpath + fileName + ".xls", FileMode.Create);//保存
        hssfworkbook.Write(fileS);
        fileS.Close();
        file.Close();
    }
}

　　

Config配置了 【ExcelMaxRow】值 65535