System.Xml.XmlUTF8TextReader.ReadQualifiedName C# (CSharp) Méthode

        private void ReadQualifiedName(PrefixHandle prefix, StringHandle localName)
        {
            int offset;
            int offsetMax;
            byte[] buffer = BufferReader.GetBuffer(out offset, out offsetMax);

            int ch = 0;
            int anyChar = 0;
            int prefixChar = 0;
            int prefixOffset = offset;
            if (offset < offsetMax)
            {
                ch = buffer[offset];
                prefixChar = ch;
                if ((s_charType[ch] & CharType.FirstName) == 0)
                    anyChar |= 0x80;
                anyChar |= ch;
                offset++;
                while (offset < offsetMax)
                {
                    ch = buffer[offset];
                    if ((s_charType[ch] & CharType.Name) == 0)
                        break;
                    anyChar |= ch;
                    offset++;
                }
            }
            else
            {
                anyChar |= 0x80;
                ch = 0;
            }
            if (ch == ':')
            {
                int prefixLength = offset - prefixOffset;
                if (prefixLength == 1 && prefixChar >= 'a' && prefixChar <= 'z')
                    prefix.SetValue(PrefixHandle.GetAlphaPrefix(prefixChar - 'a'));
                else
                    prefix.SetValue(prefixOffset, prefixLength);

                offset++;
                int localNameOffset = offset;
                if (offset < offsetMax)
                {
                    ch = buffer[offset];
                    if ((s_charType[ch] & CharType.FirstName) == 0)
                        anyChar |= 0x80;
                    anyChar |= ch;
                    offset++;
                    while (offset < offsetMax)
                    {
                        ch = buffer[offset];
                        if ((s_charType[ch] & CharType.Name) == 0)
                            break;
                        anyChar |= ch;
                        offset++;
                    }
                }
                else
                {
                    anyChar |= 0x80;
                    ch = 0;
                }
                localName.SetValue(localNameOffset, offset - localNameOffset);
                if (anyChar >= 0x80)
                {
                    VerifyNCName(prefix.GetString());
                    VerifyNCName(localName.GetString());
                }
            }
            else
            {
                prefix.SetValue(PrefixHandleType.Empty);
                localName.SetValue(prefixOffset, offset - prefixOffset);
                if (anyChar >= 0x80)
                {
                    VerifyNCName(localName.GetString());
                }
            }
            BufferReader.Advance(offset - prefixOffset);
        }