System.Text.EncoderNLS.GetBytes C# (CSharp) Method

        public unsafe override int GetBytes(char[] chars, int charIndex, int charCount,
                                              byte[] bytes, int byteIndex, bool flush)
        {
            // Validate parameters
            if (chars == null || bytes == null)
                throw new ArgumentNullException((chars == null ? nameof(chars): nameof(bytes)), SR.ArgumentNull_Array);

            if (charIndex < 0 || charCount < 0)
                throw new ArgumentOutOfRangeException((charIndex < 0 ? nameof(charIndex): nameof(charCount)), SR.ArgumentOutOfRange_NeedNonNegNum);

            if (chars.Length - charIndex < charCount)
                throw new ArgumentOutOfRangeException(nameof(chars), SR.ArgumentOutOfRange_IndexCountBuffer);

            if (byteIndex < 0 || byteIndex > bytes.Length)
                throw new ArgumentOutOfRangeException(nameof(byteIndex), SR.ArgumentOutOfRange_Index);
            Contract.EndContractBlock();

            if (chars.Length == 0)
                chars = new char[1];

            int byteCount = bytes.Length - byteIndex;
            if (bytes.Length == 0)
                bytes = new byte[1];

            // Just call pointer version
            fixed (char* pChars = chars)
                fixed (byte* pBytes = bytes)

                    // Remember that charCount is # to decode, not size of array.
                    return GetBytes(pChars + charIndex, charCount,
                                    pBytes + byteIndex, byteCount, flush);
        }