MaxKey | Access Management System-Single Sign | Authentication library

  public class program
  {  
        private static void Main()
                {
                    string table = "T_CONSIGNACION";
                    string directory = @"C:\Users\Documents\Excel"; // Put your test root here.
        
                    var dir = new DirectoryInfo(directory);
                    var file= GetNewestFile(dir);
        
                    while (file!=null)
                    {
                        if (!File.Exists(file))
                        {
                            createLog("directory: " + dir + " \nfile: " + fichero + " don't exist");
                        }
                        else
                        {
                            importFile(file, table);
                        }
                    }
                 
                }
        
        
        
        public static FileInfo GetNewestFile(DirectoryInfo directory)
                {
                    return directory.EnumerateFiles("*.*", SearchOption.AllDirectories)
                        .MaxBy(f => (f == null ? DateTime.MinValue : f.LastWriteTime));
                }
        
        public static void createLog(string logMessage)
                { 
                     ....... 
               }
        
         public static string importFile(string file, string table)
                {
                 ........
               }
           }
    
    public static class EnumerableMaxMinExt
        {
            public static TSource MaxBy(this IEnumerable source, Func selector)
            {
                return source.MaxBy(selector, Comparer.Default);
            }
    
            public static TSource MaxBy(this IEnumerable source, Func selector, IComparer comparer)
            {
                using (IEnumerator sourceIterator = source.GetEnumerator())
                {
                    if (!sourceIterator.MoveNext())
                    {
                        throw new InvalidOperationException("Sequence was empty");
                    }
    
                    TSource max = sourceIterator.Current;
                    TKey maxKey = selector(max);
    
                    while (sourceIterator.MoveNext())
                    {
                        TSource candidate = sourceIterator.Current;
                        TKey candidateProjected = selector(candidate);
    
                        if (comparer.Compare(candidateProjected, maxKey) > 0)
                        {
                            max = candidate;
                            maxKey = candidateProjected;
                        }
                    }
    
                    return max;
                }
            }
        }