外部表格格式在c＃asp.net中读取从excel到数据库的exception

问题：我从Excel表导入数据到数据库的代码对于.xls工作正常，但对于.xlsx，它给出了“外部表格不是预期的格式”。 错误。

请帮我解决一下这个。

使用的连接string是：

<add name="Excel03ConString" connectionString="Provider=Microsoft.Jet.OLEDB.4.0; Data Source={0};Extended Properties='Excel 8.0;HDR={1}'"/> <add name="Excel07ConString" connectionString="Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties='Excel 12.0;HDR={1}; IMEX=YES'"/> 

代码是：

  protected void Button2_Click(object sender, EventArgs e) { FileName = Path.GetFileName(FileUpload1.PostedFile.FileName); Extension = Path.GetExtension(FileUpload1.PostedFile.FileName); FolderPath = ConfigurationManager.AppSettings["FolderPath"]; FilePath = FileUpload1.PostedFile.FileName; Date = Calendar1.SelectedDate.ToShortDateString(); ImportData(); } void ImportData() { string conStr = ""; switch (Extension) { case ".xls": //Excel 97-03 conStr = ConfigurationManager.ConnectionStrings["Excel03ConString"] .ConnectionString; break; case ".xlsx": //Excel 07 conStr = ConfigurationManager.ConnectionStrings["Excel07ConString"] .ConnectionString; break; } try { conStr = String.Format(conStr, FilePath, "YES"); OleDbConnection Econ = new OleDbConnection(conStr); Econ.Open(); //string Query = string.Format("Select [Id],[Name],[Status] FROM [{0}]", FileName); //string Query = string.Format("Select [Id],[Name],[Status] FROM [XYZ$]"); string Query1 = string.Format("Select [Id],[Name],[Status] FROM [Sheet1$]"); OleDbCommand Ecom = new OleDbCommand(Query1, Econ); DataSet ds = new DataSet(); OleDbDataAdapter oda = new OleDbDataAdapter(Ecom); oda.Fill(ds); string sqlconn = ConfigurationManager.ConnectionStrings["TempDatabaseConnectionString"].ConnectionString; SqlConnection con = new SqlConnection(sqlconn); con.Open(); DataTable Exceldt = ds.Tables[0]; //creating object of SqlBulkCopy SqlBulkCopy objbulk = new SqlBulkCopy(con); //assigning Destination table name objbulk.DestinationTableName = "Trial"; //Mapping Table column objbulk.ColumnMappings.Add("Id", "Id"); objbulk.ColumnMappings.Add("Name", "Name"); objbulk.ColumnMappings.Add("Status", "Status"); //inserting Datatable Records to DataBase //con.Open(); objbulk.WriteToServer(Exceldt); con.Close(); ds.Clear(); Econ.Close(); Ecom.Parameters.Clear(); objbulk.Close(); } catch (Exception ex) { Response.Write(ex.ToString()); } }