Exemple #1
0
        /// <summary>
        /// Attempts to parse a field format specifier from the format string.
        /// </summary>
        protected bool ParseFormatSpecifier(TextParser format, FormatSpecifier spec)
        {
            // Return if not a field format specifier
            if (format.Peek() != '%')
            {
                return(false);
            }
            format.MoveAhead();

            // Return if "%%" (treat as '%' literal)
            if (format.Peek() == '%')
            {
                return(false);
            }

            // Test for asterisk, which indicates result is not stored
            if (format.Peek() == '*')
            {
                spec.NoResult = true;
                format.MoveAhead();
            }
            else
            {
                spec.NoResult = false;
            }

            // Parse width
            int start = format.Position;

            while (Char.IsDigit(format.Peek()))
            {
                format.MoveAhead();
            }
            if (format.Position > start)
            {
                spec.Width = int.Parse(format.Extract(start, format.Position));
            }
            else
            {
                spec.Width = 0;
            }

            // Parse modifier
            if (format.Peek() == 'h')
            {
                format.MoveAhead();
                if (format.Peek() == 'h')
                {
                    format.MoveAhead();
                    spec.Modifier = Modifiers.ShortShort;
                }
                else
                {
                    spec.Modifier = Modifiers.Short;
                }
            }
            else if (Char.ToLower(format.Peek()) == 'l')
            {
                format.MoveAhead();
                if (format.Peek() == 'l')
                {
                    format.MoveAhead();
                    spec.Modifier = Modifiers.LongLong;
                }
                else
                {
                    spec.Modifier = Modifiers.Long;
                }
            }
            else
            {
                spec.Modifier = Modifiers.None;
            }

            // Parse type
            switch (format.Peek())
            {
            case 'c':
                spec.Type = Types.Character;
                break;

            case 'd':
            case 'i':
                spec.Type = Types.Decimal;
                break;

            case 'a':
            case 'A':
            case 'e':
            case 'E':
            case 'f':
            case 'F':
            case 'g':
            case 'G':
                spec.Type = Types.Float;
                break;

            case 'o':
                spec.Type = Types.Octal;
                break;

            case 's':
                spec.Type = Types.String;
                break;

            case 'u':
                spec.Type = Types.Unsigned;
                break;

            case 'x':
            case 'X':
                spec.Type = Types.Hexadecimal;
                break;

            case '[':
                spec.Type = Types.ScanSet;
                format.MoveAhead();
                // Parse scan set characters
                if (format.Peek() == '^')
                {
                    spec.ScanSetExclude = true;
                    format.MoveAhead();
                }
                else
                {
                    spec.ScanSetExclude = false;
                }
                start = format.Position;
                // Treat immediate ']' as literal
                if (format.Peek() == ']')
                {
                    format.MoveAhead();
                }
                format.MoveTo(']');
                if (format.EndOfText)
                {
                    throw new Exception("Type specifier expected character : ']'");
                }
                spec.ScanSet = format.Extract(start, format.Position);
                break;

            default:
                string msg = String.Format("Unknown format type specified : '{0}'", format.Peek());
                throw new Exception(msg);
            }
            format.MoveAhead();
            return(true);
        }