// Get the file infoString fileName = @"C:Users ingwangDesktopprocmon.exe";FileInfo info = new FileInfo( fileName );Console.WriteLine( info.Length );FileSecurity security = info.GetAccessControl( AccessControlActions.View ); // Owner SID:Type owenerType = Type.GetType("System.Security.Principal.SecurityIdentifier");IdentityReference ownerId = info.GetAccessControl().GetOwner(owenerType);Console.WriteLine("File Owner SID is : {0}", ownerId.Value); // Account Name:NTAccount account = ( NTAccount )( ownerId.Translate( Type.GetType( "System.Security.Principal.NTAccount" ) ) );Console.WriteLine( account.Value );