CSL.BEncoding.decode_string C# (CSharp) Метод

        public static string decode_string(byte[] x, ref int f)
        {
            string s = "";
            while (x[f] != ':')
            {
                s += (char)x[f];
                f++;
            }
            f++;

            Regex r = new Regex("^(0|[1-9][0-9]*)$", RegexOptions.Compiled);

            //if (!r.IsMatch(s))
                //throw new BitTorrentException("Integer value is invalid");

            int l = int.Parse(s);
            string temp = "";
            if (l > 0)
            {
                StringBuilder sb = new StringBuilder(l);
                int i = f;
                f += l;
                while (i < f)
                    sb.Append((char)x[i++]);
                return sb.ToString();
            }
            return temp;
        }