internal static int GetKeyValuePair(string connectionString, int currentPosition, StringBuilder buffer, bool useOdbcRules, out string keyname, out string keyvalue)
{
    char chr;
    int num = currentPosition;
    buffer.Length = 0;
    keyname = null;
    keyvalue = null;
    ParserState parserState = ParserState.NothingYet;
    int length = connectionString.Length;
Label8:
    while (currentPosition < length)
    {
        chr = connectionString[currentPosition];
        ParserState parserState1 = parserState;
        if (parserState1 == ParserState.NothingYet)
        {
            if (59 == chr || char.IsWhiteSpace(chr))
            {
                goto Label2;
            }
            if (chr != 0)
            {
                if (!char.IsControl(chr))
                {
                    num = currentPosition;
                    if (61 == chr)
                    {
                        parserState = ParserState.KeyEqual;
                        goto Label2;
                    }
                    else
                    {
                        parserState = ParserState.Key;
                    }
                }
                else
                {
                    throw ADP.ConnectionStringSyntax(num);
                }
            }
            else
            {
                parserState = ParserState.NullTermination;
                goto Label2;
            }
        }
        else if (parserState1 == ParserState.Key)
        {
            if (61 != chr)
            {
                if (char.IsWhiteSpace(chr) || !char.IsControl(chr))
                {
                    goto Label4;
                }
                throw ADP.ConnectionStringSyntax(num);
            }
            else
            {
                parserState = ParserState.KeyEqual;
                goto Label2;
            }
        }
        else if (parserState1 == ParserState.KeyEqual)
        {
            if (useOdbcRules || 61 != chr)
            {
                keyname = DbConnectionOptions.GetKeyName(buffer);
                if (!ADP.IsEmpty(ref keyname))
                {
                    buffer.Length = 0;
                    parserState = ParserState.KeyEnd;
                    goto Label0;
                }
                else
                {
                    throw ADP.ConnectionStringSyntax(num);
                }
            }
            else
            {
                parserState = ParserState.Key;
            }
        }
        else if (parserState1 == ParserState.KeyEnd)
        {
            goto Label0;
        }
        else if (parserState1 == ParserState.UnquotedValue)
        {
            if (char.IsWhiteSpace(chr))
            {
                goto Label4;
            }
            if (char.IsControl(chr))
            {
                break;
            }
            if (59 != chr)
            {
                goto Label4;
            }
            break;
        }
        else if (parserState1 == ParserState.DoubleQuoteValue)
        {
            if (34 != chr)
            {
                if (chr != 0)
                {
                    goto Label4;
                }
                throw ADP.ConnectionStringSyntax(num);
            }
            else
            {
                parserState = ParserState.DoubleQuoteValueQuote;
                goto Label2;
            }
        }
        else if (parserState1 == ParserState.DoubleQuoteValueQuote)
        {
            if (34 != chr)
            {
                keyvalue = DbConnectionOptions.GetKeyValue(buffer, false);
                parserState = ParserState.QuotedValueEnd;
                goto Label1;
            }
            else
            {
                parserState = ParserState.DoubleQuoteValue;
            }
        }
        else if (parserState1 == ParserState.SingleQuoteValue)
        {
            if (39 != chr)
            {
                if (chr != 0)
                {
                    goto Label4;
                }
                throw ADP.ConnectionStringSyntax(num);
            }
            else
            {
                parserState = ParserState.SingleQuoteValueQuote;
                goto Label2;
            }
        }
        else if (parserState1 == ParserState.SingleQuoteValueQuote)
        {
            if (39 != chr)
            {
                keyvalue = DbConnectionOptions.GetKeyValue(buffer, false);
                parserState = ParserState.QuotedValueEnd;
                goto Label1;
            }
            else
            {
                parserState = ParserState.SingleQuoteValue;
            }
        }
        else if (parserState1 == ParserState.BraceQuoteValue)
        {
            if (125 != chr)
            {
                if (chr != 0)
                {
                    goto Label4;
                }
                throw ADP.ConnectionStringSyntax(num);
            }
            else
            {
                parserState = ParserState.BraceQuoteValueQuote;
            }
        }
        else if (parserState1 == ParserState.BraceQuoteValueQuote)
        {
            if (125 != chr)
            {
                keyvalue = DbConnectionOptions.GetKeyValue(buffer, false);
                parserState = ParserState.QuotedValueEnd;
                goto Label1;
            }
            else
            {
                parserState = ParserState.BraceQuoteValue;
            }
        }
        else if (parserState1 == ParserState.QuotedValueEnd)
        {
            goto Label1;
        }
        else if (parserState1 == ParserState.NullTermination)
        {
            if (chr == 0 || char.IsWhiteSpace(chr))
            {
                goto Label2;
            }
            throw ADP.ConnectionStringSyntax(currentPosition);
        }
        else
        {
            throw ADP.InternalError(InternalErrorCode.InvalidParserState1);
        }
    Label4:
        buffer.Append(chr);
        goto Label2;
    }
    ParserState parserState2 = parserState;
    switch (parserState2)
    {
        case ParserState.KeyEqual:
        case ParserState.DoubleQuoteValue:
        case ParserState.NothingYet | ParserState.Key | ParserState.KeyEqual | ParserState.KeyEnd | ParserState.UnquotedValue | ParserState.DoubleQuoteValue | ParserState.DoubleQuoteValueQuote | ParserState.SingleQuoteValue | ParserState.SingleQuoteValueQuote | ParserState.BraceQuoteValue | ParserState.BraceQuoteValueQuote | ParserState.QuotedValueEnd | ParserState.NullTermination:
        {
            if (59 == chr && currentPosition < connectionString.Length)
            {
                currentPosition++;
            }
            return currentPosition;
        }
        case ParserState.KeyEnd:
        case ParserState.SingleQuoteValue:
        case ParserState.BraceQuoteValue:
        case ParserState.QuotedValueEnd:
        {
            throw ADP.ConnectionStringSyntax(num);
        }
        case ParserState.UnquotedValue:
        {
            keyname = DbConnectionOptions.GetKeyName(buffer);
            if (!ADP.IsEmpty(ref keyname))
            {
                if (59 == chr && currentPosition < connectionString.Length)
                {
                    currentPosition++;
                }
                return currentPosition;
            }
            throw ADP.ConnectionStringSyntax(num);
        }
        case ParserState.DoubleQuoteValueQuote:
        {
            keyvalue = DbConnectionOptions.GetKeyValue(buffer, true);
            char chars = keyvalue.Chars;
            if (useOdbcRules || 39 != chars && 34 != chars)
            {
                if (59 == chr && currentPosition < connectionString.Length)
                {
                    currentPosition++;
                }
                return currentPosition;
            }
            throw ADP.ConnectionStringSyntax(num);
        }
        case ParserState.SingleQuoteValueQuote:
        case ParserState.BraceQuoteValueQuote:
        case ParserState.NullTermination:
        case ParserState.Key | ParserState.KeyEnd | ParserState.DoubleQuoteValue | ParserState.SingleQuoteValue | ParserState.BraceQuoteValue | ParserState.QuotedValueEnd:
        {
            keyvalue = DbConnectionOptions.GetKeyValue(buffer, false);
            if (59 == chr && currentPosition < connectionString.Length)
            {
                currentPosition++;
            }
            return currentPosition;
        }
    }
    throw ADP.InternalError(InternalErrorCode.InvalidParserState2);
Label0:
    if (!char.IsWhiteSpace(chr))
    {
        if (!useOdbcRules)
        {
            if (39 != chr)
            {
                if (34 != chr)
                {
                    goto Label7;
                }
                parserState = ParserState.DoubleQuoteValue;
                goto Label2;
            }
            else
            {
                parserState = ParserState.SingleQuoteValue;
                goto Label2;
            }
        }
        else
        {
            if (123 != chr)
            {
                goto Label7;
            }
            parserState = ParserState.BraceQuoteValue;
            goto Label4;
        }
    Label7:
        if (59 == chr || chr == 0)
        {
            parserState2 = parserState;
            switch (parserState2)
            {
                case ParserState.KeyEqual:
                case ParserState.DoubleQuoteValue:
                case ParserState.NothingYet | ParserState.Key | ParserState.KeyEqual | ParserState.KeyEnd | ParserState.UnquotedValue | ParserState.DoubleQuoteValue | ParserState.DoubleQuoteValueQuote | ParserState.SingleQuoteValue | ParserState.SingleQuoteValueQuote | ParserState.BraceQuoteValue | ParserState.BraceQuoteValueQuote | ParserState.QuotedValueEnd | ParserState.NullTermination:
                {
                    if (59 == chr && currentPosition < connectionString.Length)
                    {
                        currentPosition++;
                    }
                    return currentPosition;
                }
                case ParserState.KeyEnd:
                case ParserState.SingleQuoteValue:
                case ParserState.BraceQuoteValue:
                case ParserState.QuotedValueEnd:
                {
                    throw ADP.ConnectionStringSyntax(num);
                }
                case ParserState.UnquotedValue:
                {
                    keyname = DbConnectionOptions.GetKeyName(buffer);
                    if (!ADP.IsEmpty(ref keyname))
                    {
                        if (59 == chr && currentPosition < connectionString.Length)
                        {
                            currentPosition++;
                        }
                        return currentPosition;
                    }
                    throw ADP.ConnectionStringSyntax(num);
                }
                case ParserState.DoubleQuoteValueQuote:
                {
                    keyvalue = DbConnectionOptions.GetKeyValue(buffer, true);
                    char chars = keyvalue.Chars;
                    if (useOdbcRules || 39 != chars && 34 != chars)
                    {
                        if (59 == chr && currentPosition < connectionString.Length)
                        {
                            currentPosition++;
                        }
                        return currentPosition;
                    }
                    throw ADP.ConnectionStringSyntax(num);
                }
                case ParserState.SingleQuoteValueQuote:
                case ParserState.BraceQuoteValueQuote:
                case ParserState.NullTermination:
                case ParserState.Key | ParserState.KeyEnd | ParserState.DoubleQuoteValue | ParserState.SingleQuoteValue | ParserState.BraceQuoteValue | ParserState.QuotedValueEnd:
                {
                    keyvalue = DbConnectionOptions.GetKeyValue(buffer, false);
                    if (59 == chr && currentPosition < connectionString.Length)
                    {
                        currentPosition++;
                    }
                    return currentPosition;
                }
            }
            throw ADP.InternalError(InternalErrorCode.InvalidParserState2);
        }
        if (!char.IsControl(chr))
        {
            parserState = ParserState.UnquotedValue;
            goto Label4;
        }
        else
        {
            throw ADP.ConnectionStringSyntax(num);
        }
    }
Label2:
    currentPosition++;
    goto Label8;
Label1:
    if (!char.IsWhiteSpace(chr))
    {
        if (59 == chr)
        {
            parserState2 = parserState;
            switch (parserState2)
            {
                case ParserState.KeyEqual:
                case ParserState.DoubleQuoteValue:
                case ParserState.NothingYet | ParserState.Key | ParserState.KeyEqual | ParserState.KeyEnd | ParserState.UnquotedValue | ParserState.DoubleQuoteValue | ParserState.DoubleQuoteValueQuote | ParserState.SingleQuoteValue | ParserState.SingleQuoteValueQuote | ParserState.BraceQuoteValue | ParserState.BraceQuoteValueQuote | ParserState.QuotedValueEnd | ParserState.NullTermination:
                {
                    if (59 == chr && currentPosition < connectionString.Length)
                    {
                        currentPosition++;
                    }
                    return currentPosition;
                }
                case ParserState.KeyEnd:
                case ParserState.SingleQuoteValue:
                case ParserState.BraceQuoteValue:
                case ParserState.QuotedValueEnd:
                {
                    throw ADP.ConnectionStringSyntax(num);
                }
                case ParserState.UnquotedValue:
                {
                    keyname = DbConnectionOptions.GetKeyName(buffer);
                    if (!ADP.IsEmpty(ref keyname))
                    {
                        if (59 == chr && currentPosition < connectionString.Length)
                        {
                            currentPosition++;
                        }
                        return currentPosition;
                    }
                    throw ADP.ConnectionStringSyntax(num);
                }
                case ParserState.DoubleQuoteValueQuote:
                {
                    keyvalue = DbConnectionOptions.GetKeyValue(buffer, true);
                    char chars = keyvalue.Chars;
                    if (useOdbcRules || 39 != chars && 34 != chars)
                    {
                        if (59 == chr && currentPosition < connectionString.Length)
                        {
                            currentPosition++;
                        }
                        return currentPosition;
                    }
                    throw ADP.ConnectionStringSyntax(num);
                }
                case ParserState.SingleQuoteValueQuote:
                case ParserState.BraceQuoteValueQuote:
                case ParserState.NullTermination:
                case ParserState.Key | ParserState.KeyEnd | ParserState.DoubleQuoteValue | ParserState.SingleQuoteValue | ParserState.BraceQuoteValue | ParserState.QuotedValueEnd:
                {
                    keyvalue = DbConnectionOptions.GetKeyValue(buffer, false);
                    if (59 == chr && currentPosition < connectionString.Length)
                    {
                        currentPosition++;
                    }
                    return currentPosition;
                }
            }
            throw ADP.InternalError(InternalErrorCode.InvalidParserState2);
        }
        if (chr != 0)
        {
            throw ADP.ConnectionStringSyntax(num);
        }
        else
        {
            parserState = ParserState.NullTermination;
            goto Label2;
        }
    }
    else
    {
        goto Label2;
    }
}