Manually updating code blocks without lang idents.

Program.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Text.RegularExpressions;
using static System.IO.SearchOption;

namespace AddLanguageIdentifiers
{
    class Program
    {
        enum langIdents
        {
            csharp, fsharp, vb, xml, console, html, javascript, json, xaml, powershell, azurecli, azcopy, cpp, nodejs, objc, php, python, ruby, sql, swift, skip, stop
        };

        static void Main()
        {
            //string path = @"C:\Users\XXXXXXXXXX\Documents\GitHub\docs-1\docs\";
            string path = @"C:\Users\XXXXXXXXXX\Documents\GitHub\docs-1\docs\csharp\language-reference\compiler-options\";
            //string path = @"C:\_DOCS_SCRIPTS\add-lang-ids\";

            var files = Directory.EnumerateFiles(path, "*.md", AllDirectories);

            Regex regExp = new Regex(@"^(csharp|fsharp|vb|xml|console|html|javascript|json|xaml|powershell|azurecli|azcopy|cpp|nodejs|objc|php|python|ruby|sql|swift)", RegexOptions.Compiled);

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

                var changed = false;
                var fileText = File.ReadAllText(file);
                var brokenText = fileText.Split("```");
                var joinedText = new StringBuilder();
                var code = false;
                var continueProcessingFiles = true;

                foreach (var segment in brokenText)
                {
                    if (code)
                    {
                        if (regExp.IsMatch(segment))
                        {
                            joinedText.Append($"```{segment}```");
                        }
                        else
                        {
                            Console.Clear();
                            Console.WriteLine(file);
                            Console.WriteLine();
                            Console.WriteLine(segment);
                            Console.WriteLine();
                            Console.WriteLine("csharp=0 fsharp=1 vb=2 xml=3 console=4 html=5 javascript=6 json=7 xaml=8 powershell=9 azurecli=10 azcopy=11 cpp=12 nodejs=13 objc=14 php=15 python=16 ruby=17 sql=18 swift=19 skip=20 stop=21");

                            int x;
                            do
                            {
                                x = ReadLine();
                            } while (!Enum.IsDefined(typeof(langIdents), x));

                            if (x == 21)
                            {
                                changed = false;
                                continueProcessingFiles = false;
                                break;
                            }

                            if (x == 20)
                            {
                                joinedText.Append($"```{segment}```");
                            }
                            else
                            {
                                joinedText.Append($"```{(langIdents)x}{segment}```");
                                changed = true;
                            }
                        }
                    }
                    else
                    {
                        joinedText.Append($"{segment}");
                    }
                    code = !code;
                }
                if (changed)
                {
                    File.WriteAllText(file, joinedText.ToString());
                }
                if (!continueProcessingFiles)
                {
                    break;
                }
                Console.WriteLine();
            }
        }

        static int ReadLine()
        {
            while (true)
            {
                var ch = Console.ReadLine();
                int result;
                if (int.TryParse(ch, out result))
                {
                    return result;
                }
            }
        }
    }
}