在客户端（非服务端） ，选择本地文件夹，一次导出多个excel。

前台：

<div>
      <asp:LinkButton class="linktext" id="lnbExcel" runat="server" onclick="lnbExcel_Click" >
      导出excel</asp:LinkButton>
    </div>
      <script>
    function browseFolder(path) {


    try {


        var Message = "\u8bf7\u9009\u62e9\u6587\u4ef6\u5939"; //选择框提示信息


        var Shell = new ActiveXObject("Shell.Application");


        var Folder = Shell.BrowseForFolder(0, Message, 64, 17); //起始目录为：我的电脑


        //var Folder = Shell.BrowseForFolder(0, Message, 0); //起始目录为：桌面


        if (Folder != null) {


            Folder = Folder.items(); // 返回 FolderItems 对象


            Folder = Folder.item(); // 返回 Folderitem 对象


            Folder = Folder.Path; // 返回路径


            if (Folder.charAt(Folder.length - 1) != "\\") {


                Folder = Folder + "\\";
            }
            document.getElementById(path).value = Folder;


            return Folder;


        }


    }


    catch (e) {


        alert(e.message);


    }


}
 </script>
<table>


  <tr>


    <td>选择导入数据源：</td>


    <td><asp:TextBox ID="path"
            runat="server"></asp:TextBox></td>


    <td><input type=button value="选择" onclick="browseFolder('path')"></td>


  </tr>


</table>

后台 

 //导出EXCEL
        protected void lnbExcel_Click(object sender, EventArgs e)
        {
            #region dataTable导出到excel 弹出保存对话框
            for (int i = 0; i < 2; i++)
            {
                string saveFileName = path.Text + i;


                int rowIndex = 1;      //开始写入数据的单元格行
                int colIndex = 0;      //开始写入数据的单元格列
                System.Reflection.Missing miss = System.Reflection.Missing.Value;
                Microsoft.Office.Interop.Excel.Application mExcel = new Microsoft.Office.Interop.Excel.Application();
                mExcel.Visible = false;
                Microsoft.Office.Interop.Excel.Workbooks mBooks = (Microsoft.Office.Interop.Excel.Workbooks)mExcel.Workbooks;
                Microsoft.Office.Interop.Excel.Workbook mBook = (Microsoft.Office.Interop.Excel.Workbook)(mBooks.Add(miss));
                Microsoft.Office.Interop.Excel.Worksheet mSheet = (Microsoft.Office.Interop.Excel.Worksheet)mBook.ActiveSheet;
                //Microsoft.Office.Interop.Excel.Range er = mSheet.get_Range((object)"A1", System.Reflection.Missing.Value); //向Excel文件中写入标题文本
                //er.Value2 = fileName.Substring(0, fileName.LastIndexOf('.'));
                try
                {
                    colIndex++;
                    mSheet.Cells[1, colIndex] = "列1";//输出DataGridView列头名   




                    rowIndex++;
                    colIndex = 0;
                    colIndex++;
                    mSheet.Cells[rowIndex, colIndex] = "'" + "支部到";






                    //获取你使用的excel 的版本号
                    string _strVersion = mExcel.Version;
                    int FormatNum = 0x00;
                    if (Convert.ToDouble(_strVersion) < 12)//You use Excel 97-2003
                    {


                        FormatNum = -4143;


                    }


                    else//you use excel 2007 or later
                    {


                        FormatNum = 56;
                    }


                    //保存工作已写入数据的工作表
                    mBook.SaveAs(saveFileName, FormatNum, miss, miss, miss, miss, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, miss, miss, miss, miss);


                    //mBook.SaveAs(saveFileName, FormatNum, miss, miss, miss, miss, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, miss, miss, miss, miss);
                }
                catch (Exception ee)
                {
                    throw new Exception(ee.Message);
                }
                            finally    //finally中的代码主要用来释放内存和中止进程()
                {
                    mBook.Close(true, miss, miss);
                    mBooks.Close();
                    mExcel.Quit();
                    //System.Runtime.InteropServices.Marshal.ReleaseComObject(er);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(mSheet);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(mBook);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(mBooks);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(mExcel);
                    GC.Collect();
                }
            }
            #endregion

命名空间  using Microsoft.Office.Interop.Excel;

IE测试通过。在文件名冲突时可能报其他错误。

另，在可能受服务端excel配置影响报一下错误：

附加决解方案连接 http://blog.csdn.net/zijings8374/article/details/4256005 （未测试 0..0）

检索COM 类工厂中CLSID 为 {00024500-0000-0000-C000-000000000046}的组件时失败