读取上载的文件时出错。xls excel文件在asp。网

现在,用户对文件进行更改,然后再次上传,从这里我阅读了上传的内容。xls文件,并在数据库中进行必要的更改。

外部表不在预期的范围内 总体安排

我让用户下载文件作为

System.Web.HttpResponse response = System.Web.HttpContext.Current.Response;
            // first let's clean up the response.object
            response.Clear();
            response.Charset = "";
            // set the response mime type for excel
            response.ContentType = "application/vnd.ms-excel";
            response.AddHeader("Content-Disposition", "attachment;filename=\"" + filename + "\"");
            // create a string writer
            using (System.IO.StringWriter sw = new System.IO.StringWriter())
            {
                using (System.Web.UI.HtmlTextWriter htw = new System.Web.UI.HtmlTextWriter(sw))
                {
                    // instantiate a datagrid
                    System.Web.UI.WebControls.DataGrid dg = new System.Web.UI.WebControls.DataGrid();
                    dg.DataSource = dt;
                    dg.DataBind();
                    dg.RenderControl(htw);
                    response.Write(sw.ToString());
                    response.End();
                }
            }

用户在进行更改后上载该文件,我正在以

string connString = "Provider=Microsoft.Jet.OLEDB.4.0;" +
                "Data Source=" + path + "\\" + FileUpload1.FileName + ";Extended Properties=Excel 8.0;";
                    OleDbConnection oledbConn = new OleDbConnection(connString);

                    oledbConn.Open();

                    OleDbCommand cmd = new OleDbCommand("SELECT * FROM [$Sheet1 ", oledbConn);
                    OleDbDataAdapter oleda = new OleDbDataAdapter();
                    oleda.SelectCommand = cmd;

                    DataSet ds = new DataSet();

                    oleda.Fill(ds, "Employees");

请帮忙。谢谢