protected void ExportOriginalData()
        {
            Stream mystream;
            Connection con = new Connection();
            SqlConnection conn;
            conn = con.Create();
            conn.Open();
            SqlDataAdapter da = new SqlDataAdapter("select * from data", conn);
            DataSet ds = new DataSet();
            da.Fill(ds, "mytable");

            DataTable dt = ds.Tables["mytable"];
            if ((mystream = saveFileDialog1.OpenFile()) != null)
            {
                System.IO.StreamWriter sw = new StreamWriter(mystream, System.Text.Encoding.Default);

                for (int i = 0; i < dt.Columns.Count; i++)
                {
                    sw.Write(dt.Columns[i].ColumnName.ToString() + "\t");
                }
                sw.WriteLine();
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        sw.Write(dt.Rows[i][j].ToString().Replace("\r\n", "").Replace("\t", "") + "\t");
                    }
                    sw.WriteLine();
                }
                sw.Close();
                mystream.Close();
            }
            ChangeStatus(false);
        }

------解决方案--------------------
http://www.cnblogs.com/dengxinghong/archive/2008/04/04/1137853.html

------解决方案--------------------

C#,GridView导出到Excel

  /// <summary>
      /// 导出到Excel
      /// </summary>
      /// <param name="dgv"></param>
      /// <param name="title"></param>
      public static void DataGridViewToExcel(DataGridView dgv, string title)
      {
          if (dgv.DataSource == null || dgv.Columns.Count == 0)
          {
              return;
          }
          Excel.Application exc = new Excel.ApplicationClass();
          if (exc == null)
          {
              throw new Exception("Excel无法启动");
          }
          Workbooks workbooks = exc.Workbooks;
          _Workbook workbook = workbooks.Add(XlWBATemplate.xlWBATWorksheet);
          Sheets sheets = exc.Sheets;
          _Worksheet worksheet = (_Worksheet)sheets[1];
          if (worksheet == null)
          {
              throw new Exception("Worksheet error");
          }  

          DataGridViewClipboardCopyMode bakMode = dgv.ClipboardCopyMode;
          bool copyCurrentCellText = true;
          bool showRowHeader = dgv.RowHeadersVisible;
          if (dgv is gvGridView)
          {
              copyCurrentCellText = ((gvGridView)dgv).CopyCurrentCellText;
              ((gvGridView)dgv).CopyCurrentCellText = false;
          }
          dgv.RowHeadersVisible = false;  

          IDataObject bakClipbordDasta = Clipboard.GetDataObject();  

          dgv.ClipboardCopyMode = DataGridViewClipboardCopyMode.EnableAlwaysIncludeHeaderText;
          IDataObject exportData = dgv.GetClipboardContent();
          if (exportData != null)
          {
              DataObject data = exportData as DataObject;
              Clipboard.SetDataObject(data.GetText(TextDataFormat.UnicodeText));
          }
          if (dgv is gvGridView)
          {
              ((gvGridView)dgv).CopyCurrentCellText = copyCurrentCellText;
          }
          dgv.RowHeadersVisible = showRowHeader