System.Xml.UTF16Decoder.GetChars C# (CSharp) Méthode

        public override int GetChars( byte[] bytes, int byteIndex, int byteCount, char[] chars, int charIndex ) {
            int charCount = GetCharCount( bytes, byteIndex, byteCount );

            if ( lastByte >= 0 ) {
                if ( byteCount == 0 ) {
                    return charCount;
                }
                int nextByte = bytes[byteIndex++];
                byteCount--;

                chars[charIndex++] = bigEndian
                    ? (char)( lastByte << 8 | nextByte )
                    : (char)( nextByte << 8 | lastByte );
                lastByte = -1;
            }

            if ( ( byteCount & 1 ) != 0 ) {
                lastByte = bytes[byteIndex + --byteCount];
            }

            // use the fast BlockCopy if possible
            if ( bigEndian == BitConverter.IsLittleEndian ) {
                int byteEnd = byteIndex + byteCount;
                if ( bigEndian ) {
                    while ( byteIndex < byteEnd ) {
                        int hi = bytes[byteIndex++];
                        int lo = bytes[byteIndex++];
                        chars[charIndex++] = (char)( hi << 8 | lo );
                    }                    
                }
                else {
                    while ( byteIndex < byteEnd ) {
                        int lo = bytes[byteIndex++];
                        int hi = bytes[byteIndex++];
                        chars[charIndex++] = (char)( hi << 8 | lo );
                    }
                }
            }
            else {
                Buffer.BlockCopy( bytes, byteIndex, chars, charIndex * CharSize, byteCount );
            }
            return charCount;
        }