C#自动判断Excel版本使用不同的连接字符串

  /// <summary>  /// 把数据从Excel装载到DataTable  /// </summary>  /// <param name="pathName">带路径的Excel文件名</param>  /// <param name="sheetName">工作表名</param>  /// <param name="tbContainer">将数据存入的DataTable</param>  /// <returns></returns>  public DataTable ExcelToDataTable(string pathName, string sheetName)  {    DataTable tbContainer = new DataTable();    string strConn = string.Empty;    if (string.IsNullOrEmpty(sheetName)) { sheetName = "Sheet1"; }    FileInfo file = new FileInfo(pathName);    if (!file.Exists) { throw new Exception("文件不存在"); }    string extension = file.Extension;    switch (extension)    {      case ".xls":        strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1;'";        break;      case ".xlsx":        strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + pathName + ";Extended Properties='Excel 12.0;HDR=Yes;IMEX=1;'";        break;      default:        strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathName + ";Extended Properties='Excel 8.0;HDR=Yes;IMEX=1;'";        break;    }    //链接Excel    OleDbConnection cnnxls = new OleDbConnection(strConn);    //读取Excel里面有 表Sheet1    OleDbDataAdapter oda = new OleDbDataAdapter(string.Format("select * from [{0}$]", sheetName), cnnxls);    DataSet ds = new DataSet();    //将Excel里面有表内容装载到内存表中！    oda.Fill(tbContainer);    return tbContainer;  }