confusion in if else logic condition in c# :     
            if (filesxt.Extension.ToString()==".rar")
            {
                NUnrar.Archive.RarArchive.WriteToDirectory(Sourcepath, Destination, NUnrar.Common.ExtractOptions.ExtractFullPath | NUnrar.Common.ExtractOptions.Overwrite);

            }
            else if (filesxt.Extension.ToString() == ".zip") 
            {
                UnZipFromMTAThread(Sourcepath, Destination);
            }

but if it is .rar and the above method gives error then it should perform this method

    ExtractFile(Sourcepath, Destination);

What would be the logic? Can anyone help?
Thanks