System.Data.SqlClient.TdsParser.TryProcessError C# (CSharp) Method

        internal bool TryProcessError(byte token, TdsParserStateObject stateObj, out SqlError error)
        {
            ushort shortLen;
            byte byteLen;
            int number;
            byte state;
            byte errorClass;

            error = null;

            if (!stateObj.TryReadInt32(out number))
            {
                return false;
            }
            if (!stateObj.TryReadByte(out state))
            {
                return false;
            }
            if (!stateObj.TryReadByte(out errorClass))
            {
                return false;
            }

            Debug.Assert(((errorClass >= TdsEnums.MIN_ERROR_CLASS) && token == TdsEnums.SQLERROR) ||
                          ((errorClass < TdsEnums.MIN_ERROR_CLASS) && token == TdsEnums.SQLINFO), "class and token don't match!");

            if (!stateObj.TryReadUInt16(out shortLen))
            {
                return false;
            }
            string message;
            if (!stateObj.TryReadString(shortLen, out message))
            {
                return false;
            }

            if (!stateObj.TryReadByte(out byteLen))
            {
                return false;
            }

            string server;

            // If the server field is not received use the locally cached value.
            if (byteLen == 0)
            {
                server = _server;
            }
            else
            {
                if (!stateObj.TryReadString(byteLen, out server))
                {
                    return false;
                }
            }

            if (!stateObj.TryReadByte(out byteLen))
            {
                return false;
            }
            string procedure;
            if (!stateObj.TryReadString(byteLen, out procedure))
            {
                return false;
            }

            int line;
            if (_isYukon)
            {
                if (!stateObj.TryReadInt32(out line))
                {
                    return false;
                }
            }
            else
            {
                ushort shortLine;
                if (!stateObj.TryReadUInt16(out shortLine))
                {
                    return false;
                }
                line = shortLine;
                // If we haven't yet completed processing login token stream yet, we may be talking to a Yukon server
                // In that case we still have to read another 2 bytes
                if (_state == TdsParserState.OpenNotLoggedIn)
                {
                    // Login incomplete
                    byte b;
                    if (!stateObj.TryPeekByte(out b))
                    {
                        return false;
                    }
                    if (b == 0)
                    {
                        // This is an invalid token value
                        ushort value;
                        if (!stateObj.TryReadUInt16(out value))
                        {
                            return false;
                        }
                        line = (line << 16) + value;
                    }
                }
            }

            error = new SqlError(number, state, errorClass, _server, message, procedure, line);
            return true;
        }