Patches Hosts file entities (add & update )

HostsFilePatcher.cs

 private static void PatchHosts()
        {
            string HostFileLocation = @"C:\Windows\System32\drivers\etc\hosts";
            Regex rgxHosts = new Regex(@"\b((\d{1,3}\.){3}\d{1,3})\b[	 ]+([a-zA-Z0-9.]+)", RegexOptions.ECMAScript | RegexOptions.Compiled);
            List<String> HostsFile = new List<string>(File.ReadAllLines(HostFileLocation));

            //Parse Entities into an easy <domain,ip> list
            var myDict = HostsFile
                .Select(m => m.Split("#")[0]).Where(m => m != "")
                .Select(m => rgxHosts.Match(m))
                .Where(m => m.Groups.Count >= 3)
                .ToDictionary(m => m.Groups[3].Value, m => m.Groups[1].Value);

            myDict["ffasx.de"] = "127.0.0.1";

            //Replace already existing entities
            for (int i = 0; i < HostsFile.Count; i++)
            {
                for (int a = myDict.Count - 1; a >= 0; a--)
                {
                    var item = myDict.ElementAt(a);
                    if (HostsFile[i].Contains(item.Key))
                    {
                        HostsFile[i] = item.Value + " " + item.Key;
                        myDict.Remove(item.Key);
                    }
                }
            }
            //Add remaining Items which werent in the dictionary in the first place
            foreach (var item in myDict)
            {
                HostsFile.Add(item.Value + " " + item.Key);
            }
            //Save changes
            File.WriteAllLines(HostFileLocation, HostsFile);
        }