Encoding files with UTF8 BOM

gistfile1.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace UTF8BOM
{
    class Program
    {
        static void Main(string[] args)
        {
            var isForce = args.Any(arg => arg == "-f");
            var dir = args.FirstOrDefault(arg => !arg.StartsWith("-")) ?? ".";
            var path = Path.GetFullPath(dir);
            var pathUri = new Uri(path, UriKind.Absolute);
            var replaceCRLF = args.Any(arg => arg == "--crlf");

            EncodeFiles(isForce, path, pathUri);
            if (replaceCRLF)
            {
                ReplaceCRLF(path, pathUri);
            }
        }

        private static void EncodeFiles(bool isForce, string path, Uri pathUri)
        {
            var dirEnumerable = Directory.EnumerateFiles(path, "*.js", SearchOption.AllDirectories);
            var files = DetectNoBom(dirEnumerable).ToList();

            if (files.Count == 0)
            {
                Console.WriteLine("All js files were encoded with BOM already.");
                return;
            }

            foreach (var file in files)
            {
                Console.WriteLine(file);
            }

            if (!isForce)
            {
                Console.Write("Encode these files? [y/N]: ");
                var yN = Console.ReadLine();
                if (!Regex.IsMatch(yN, "(y|yes)", RegexOptions.IgnoreCase))
                {
                    return;
                }
            }

            foreach (var file in files)
            {
                var uri = new Uri(file, UriKind.Absolute);
                var relative = pathUri.MakeRelativeUri(uri);
                Console.WriteLine("Encoding " + relative);

                var text = File.ReadAllText(file);
                File.WriteAllText(file, text, new UTF8Encoding(true));
            }
        }

        private static void ReplaceCRLF(string path, Uri pathUri)
        {
            const string pattern = @"((?<!\r)\n|\r(?!\n))";
            var dirEnumerable = Directory.EnumerateFiles(path, "*.js", SearchOption.AllDirectories);
            foreach (var file in dirEnumerable)
            {
                var text = File.ReadAllText(file);
                if (Regex.IsMatch(text, pattern, RegexOptions.Multiline))
                {
                    var uri = new Uri(file, UriKind.Absolute);
                    var relative = pathUri.MakeRelativeUri(uri);
                    Console.WriteLine("Normalizing Line " + relative);

                    text = Regex.Replace(text, pattern, "\r\n", RegexOptions.Multiline); // CRLF
                    File.WriteAllText(file, text, new UTF8Encoding(true));
                }
            }
        }

        private static IEnumerable<string> DetectNoBom(IEnumerable<string> files)
        {
            // http://unicode.org/faq/utf_bom.html#bom4
            var bytes = new byte[] { 0xef, 0xbb, 0xbf };
            foreach (var file in files)
            {
                using (var stream = File.OpenRead(file))
                {
                    var readBytes = new byte[3];
                    stream.Read(readBytes, 0, 3);
                    if (!bytes.SequenceEqual(readBytes))
                    {
                        yield return file;
                    }
                }
            }
        }
    }
}