BaseNcoding.Base128.Encode C# (CSharp) Метод

        public override string Encode(byte[] data)
        {
            int dataLength = data.Length;
            StringBuilder result = new StringBuilder((dataLength + 6) / 7 * 8);

            byte x1, x2;
            int i;

            int length7 = (dataLength / 7) * 7;
            for (i = 0; i < length7; i += 7)
            {
                x1 = data[i];
                result.Append(Alphabet[x1 >> 1]);

                x2 = data[i + 1];
                result.Append(Alphabet[((x1 << 6) & 0x40) | (x2 >> 2)]);

                x1 = data[i + 2];
                result.Append(Alphabet[((x2 << 5) & 0x60) | (x1 >> 3)]);

                x2 = data[i + 3];
                result.Append(Alphabet[((x1 << 4) & 0x70) | (x2 >> 4)]);

                x1 = data[i + 4];
                result.Append(Alphabet[((x2 << 3) & 0x78) | (x1 >> 5)]);

                x2 = data[i + 5];
                result.Append(Alphabet[((x1 << 2) & 0x7C) | (x2 >> 6)]);

                x1 = data[i + 6];
                result.Append(Alphabet[((x2 << 1) & 0x7E) | (x1 >> 7)]);
                result.Append(Alphabet[x1 & 0x7F]);
            }

            switch (dataLength - length7)
            {
                case 1:
                    x1 = data[i];
                    result.Append(Alphabet[x1 >> 1]);
                    result.Append(Alphabet[(x1 << 6) & 0x40]);

                    result.Append(Special, 6);
                    break;
                case 2:
                    x1 = data[i];
                    result.Append(Alphabet[x1 >> 1]);
                    x2 = data[i + 1];
                    result.Append(Alphabet[((x1 << 6) & 0x40) | (x2 >> 2)]);
                    result.Append(Alphabet[((x2 << 5) & 0x60)]);

                    result.Append(Special, 5);
                    break;
                case 3:
                    x1 = data[i];
                    result.Append(Alphabet[x1 >> 1]);
                    x2 = data[i + 1];
                    result.Append(Alphabet[((x1 << 6) & 0x40) | (x2 >> 2)]);
                    x1 = data[i + 2];
                    result.Append(Alphabet[((x2 << 5) & 0x60) | (x1 >> 3)]);
                    result.Append(Alphabet[(x1 << 4) & 0x70]);

                    result.Append(Special, 4);
                    break;
                case 4:
                    x1 = data[i];
                    result.Append(Alphabet[x1 >> 1]);
                    x2 = data[i + 1];
                    result.Append(Alphabet[((x1 << 6) & 0x40) | (x2 >> 2)]);
                    x1 = data[i + 2];
                    result.Append(Alphabet[((x2 << 5) & 0x60) | (x1 >> 3)]);
                    x2 = data[i + 3];
                    result.Append(Alphabet[((x1 << 4) & 0x70) | (x2 >> 4)]);
                    result.Append(Alphabet[(x2 << 3) & 0x78]);

                    result.Append(Special, 3);
                    break;
                case 5:
                    x1 = data[i];
                    result.Append(Alphabet[x1 >> 1]);
                    x2 = data[i + 1];
                    result.Append(Alphabet[((x1 << 6) & 0x40) | (x2 >> 2)]);
                    x1 = data[i + 2];
                    result.Append(Alphabet[((x2 << 5) & 0x60) | (x1 >> 3)]);
                    x2 = data[i + 3];
                    result.Append(Alphabet[((x1 << 4) & 0x70) | (x2 >> 4)]);
                    x1 = data[i + 4];
                    result.Append(Alphabet[((x2 << 3) & 0x78) | (x1 >> 5)]);
                    result.Append(Alphabet[(x1 << 2) & 0x7C]);

                    result.Append(Special, 2);
                    break;
                case 6:
                    x1 = data[i];
                    result.Append(Alphabet[x1 >> 1]);
                    x2 = data[i + 1];
                    result.Append(Alphabet[((x1 << 6) & 0x40) | (x2 >> 2)]);
                    x1 = data[i + 2];
                    result.Append(Alphabet[((x2 << 5) & 0x60) | (x1 >> 3)]);
                    x2 = data[i + 3];
                    result.Append(Alphabet[((x1 << 4) & 0x70) | (x2 >> 4)]);
                    x1 = data[i + 4];
                    result.Append(Alphabet[((x2 << 3) & 0x78) | (x1 >> 5)]);
                    x2 = data[i + 5];
                    result.Append(Alphabet[((x1 << 2) & 0x7C) | (x2 >> 6)]);
                    result.Append(Alphabet[(x2 << 1) & 0x7E]);

                    result.Append(Special);
                    break;
            }

            return result.ToString();
        }