Excel connection string

FileUpload1.SaveAs(fileLocation);

     //Check whether file extension is xls or xslx

        if (fileExtension == ".xls")
     {
          connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" fileLocation ";Extended Properties=\"Excel 8.0;HDR=Yes;IMEX=2\"";
       }
          else if (fileExtension == ".xlsx")
        {
            connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" fileLocation ";Extended Properties=\"Excel 12.0;HDR=Yes;IMEX=2\"";
           }