TLD Regex Generator for PiHole and AdGuard

TLDGenerator.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using System.Net.Http;

internal class Program
{
    private static async Task Main(string[] args)
    {
        using (HttpClient client = new HttpClient())
        {
            var response = await client.GetAsync("https://data.iana.org/TLD/tlds-alpha-by-domain.txt");
            var data = await response.Content.ReadAsStreamAsync();

            StreamReader reader = new StreamReader(data);
            var text = await reader.ReadLineAsync();

            List<string> tlds = new List<string>();

            while (text != null)
            {
                tlds.Add(text.ToLower());
                text = await reader.ReadLineAsync();
            }

            reader.Close();
            reader.Dispose();

            Console.WriteLine($"Total Number of TLDs: {tlds.Count}");

            Console.WriteLine("Removing WhiteListed TLDs...");
            //Use this to whitelist TLDs
            string[] tldsToRemove = { "youtube", "us", "uk", "tv", "sbi", "org", "net", "ms", "kr", "jp", "io", "info", "in", "hk", "gov", "fr", "eu", "edu", "dk", "de", "com", "co", "ch", "ca", "biz", "azure", "aws", "au", "nz", "nl", "arpa", "dev","to","me" };

            foreach (var tld in tldsToRemove)
            {
                tlds.Remove(tld);
            }

            tlds.RemoveAt(0); //Removing # Version

            Console.WriteLine($"Total Number of TLDs after whitelisting: {tlds.Count}");

            while (true)
            {
                Console.WriteLine("Menu:");
                Console.WriteLine("TLD Blocking Generator for PiHole and AdGuard Home:");
                Console.WriteLine("1. PiHole TLD List");
                Console.WriteLine("2. AdGuard TLD List");
                Console.WriteLine("3. Exit");

                Console.WriteLine("Please enter 1(PiHole) or 2(AdGuard Home): ");

                //1. PiHole
                //2. AdGuard home
                int input = int.Parse(Console.ReadLine());

                Console.WriteLine("-----------------------------------");

                switch (input)
                {
                    case 1:
                        Console.WriteLine("Generating TLD List for PiHole...");

                        StreamWriter writerPiHole = new StreamWriter($@"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}\tldsForPihole.txt");

                        foreach (var item in tlds)
                        {
                            //using Pihole Regex Format
                            //(\.|^)ad$
                            await writerPiHole.WriteLineAsync($"(\\.|^){item}$");
                        }

                        writerPiHole.Close();
                        writerPiHole.Dispose();
                        Console.WriteLine("PiHole TLD List Generated Successfully..");
                        Console.WriteLine($"Pihole TLD List Available at: {Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}\\tldsForPihole.txt\"");
                        break;
                    case 2:
                        Console.WriteLine("Generating TLD List for AdGuard Home...");

                        StreamWriter writerAdGuard = new StreamWriter($@"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}\tldsForAdGuard.txt");

                        foreach (var item in tlds)
                        {
                            //using AdGuard Home Regex Format
                            //await writerAdGuard.WriteLineAsync($"||{item}^");
                            await writerAdGuard.WriteLineAsync($"||*.{item}^");
                        }

                        writerAdGuard.Close();
                        writerAdGuard.Dispose();
                        Console.WriteLine("AdGuard Home TLD List Generated Successfully..");
                        Console.WriteLine($"AdGuard Home TLD List Available at: {Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}\\tldsForAdGuard.txt\"");
                        break;
                    case 3:
                        Environment.Exit(0);
                        break;
                }
            }
        }          
    }
}

This TLD Regex Generator code is also available on .NET Fiddle.

https://dotnetfiddle.net/OaKKqD