Esempi in C# (CSharp) per System.Text.RegularExpressions RegexBoyerMoore.Scan

Scan() private method

Scan uses the Boyer-Moore algorithm to find the first occurrence of the specified string within text, beginning at index, and constrained within beglimit and endlimit. The direction and case-sensitivity of the match is determined by the arguments to the RegexBoyerMoore constructor.

private Scan ( string text, int index, int beglimit, int endlimit ) : int
text	string
index	int
beglimit	int
endlimit	int
return	int

Esempio n. 1

        protected override bool FindFirstChar()
        {
            int    i;
            String set;

            if (0 != (runanchors & (RegexFCD.Beginning | RegexFCD.Start | RegexFCD.EndZ | RegexFCD.End)))
            {
                if (!runcode._rightToLeft)
                {
                    if ((0 != (runanchors & RegexFCD.Beginning) && runtextpos > runtextbeg) ||
                        (0 != (runanchors & RegexFCD.Start) && runtextpos > runtextstart))
                    {
                        runtextpos = runtextend;
                        return(false);
                    }
                    if (0 != (runanchors & RegexFCD.EndZ) && runtextpos < runtextend - 1)
                    {
                        runtextpos = runtextend - 1;
                    }
                    else if (0 != (runanchors & RegexFCD.End) && runtextpos < runtextend)
                    {
                        runtextpos = runtextend;
                    }
                }
                else
                {
                    if ((0 != (runanchors & RegexFCD.End) && runtextpos < runtextend) ||
                        (0 != (runanchors & RegexFCD.EndZ) && (runtextpos < runtextend - 1 ||
                                                               (runtextpos == runtextend - 1 && CharAt(runtextpos) != '\n'))) ||
                        (0 != (runanchors & RegexFCD.Start) && runtextpos < runtextstart))
                    {
                        runtextpos = runtextbeg;
                        return(false);
                    }
                    if (0 != (runanchors & RegexFCD.Beginning) && runtextpos > runtextbeg)
                    {
                        runtextpos = runtextbeg;
                    }
                }

                if (runbmPrefix != null)
                {
                    return(runbmPrefix.IsMatch(runtext, runtextpos, runtextbeg, runtextend));
                }
            }
            else if (runbmPrefix != null)
            {
                runtextpos = runbmPrefix.Scan(runtext, runtextpos, runtextbeg, runtextend);

                if (runtextpos == -1)
                {
                    runtextpos = (runcode._rightToLeft ? runtextbeg : runtextend);
                    return(false);
                }

                return(true);
            }

            if (runfcPrefix == null)
            {
                return(true);
            }

            runrtl = runcode._rightToLeft;
            runci  = runfcPrefix.CaseInsensitive;
            set    = runfcPrefix.Prefix;

            if (RegexCharClass.IsSingleton(set))
            {
                char ch = RegexCharClass.SingletonChar(set);

                for (i = Forwardchars(); i > 0; i--)
                {
                    if (ch == Forwardcharnext())
                    {
                        Backwardnext();
                        return(true);
                    }
                }
            }
            else
            {
                for (i = Forwardchars(); i > 0; i--)
                {
                    if (RegexCharClass.CharInSet(Forwardcharnext(), set, String.Empty))
                    {
                        Backwardnext();
                        return(true);
                    }
                }
            }
            return(false);
        }

Esempio n. 2

        protected override bool FindFirstChar()
        {
            int    i;
            String set;

            if (0 != (_runanchors & (RegexFCD.Beginning | RegexFCD.Start | RegexFCD.EndZ | RegexFCD.End)))
            {
                if (!_runcode._rightToLeft)
                {
                    if ((0 != (_runanchors & RegexFCD.Beginning) && _runtextpos > _runtextbeg) ||
                        (0 != (_runanchors & RegexFCD.Start) && _runtextpos > _runtextstart))
                    {
                        _runtextpos = _runtextend;
                        return(false);
                    }
                    if (0 != (_runanchors & RegexFCD.EndZ) && _runtextpos < _runtextend - 1)
                    {
                        _runtextpos = _runtextend - 1;
                    }
                    else if (0 != (_runanchors & RegexFCD.End) && _runtextpos < _runtextend)
                    {
                        _runtextpos = _runtextend;
                    }
                }
                else
                {
                    if ((0 != (_runanchors & RegexFCD.End) && _runtextpos < _runtextend) ||
                        (0 != (_runanchors & RegexFCD.EndZ) && (_runtextpos < _runtextend - 1 ||
                                                                (_runtextpos == _runtextend - 1 && CharAt(_runtextpos) != '\n'))) ||
                        (0 != (_runanchors & RegexFCD.Start) && _runtextpos < _runtextstart))
                    {
                        _runtextpos = _runtextbeg;
                        return(false);
                    }
                    if (0 != (_runanchors & RegexFCD.Beginning) && _runtextpos > _runtextbeg)
                    {
                        _runtextpos = _runtextbeg;
                    }
                }

                if (_runbmPrefix != null)
                {
                    return(_runbmPrefix.IsMatch(_runtext, _runtextpos, _runtextbeg, _runtextend));
                }

                return(true); // found a valid start or end anchor
            }
            else if (_runbmPrefix != null)
            {
                _runtextpos = _runbmPrefix.Scan(_runtext, _runtextpos, _runtextbeg, _runtextend);

                if (_runtextpos == -1)
                {
                    _runtextpos = (_runcode._rightToLeft ? _runtextbeg : _runtextend);
                    return(false);
                }

                return(true);
            }
            else if (_runfcPrefix == null)
            {
                return(true);
            }

            _runrtl = _runcode._rightToLeft;
            _runci  = _runfcPrefix.CaseInsensitive;
            set     = _runfcPrefix.Prefix;

            if (RegexCharClass.IsSingleton(set))
            {
                char ch = RegexCharClass.SingletonChar(set);

                for (i = Forwardchars(); i > 0; i--)
                {
                    if (ch == Forwardcharnext())
                    {
                        Backwardnext();
                        return(true);
                    }
                }
            }
            else
            {
                for (i = Forwardchars(); i > 0; i--)
                {
                    if (RegexCharClass.CharInClass(Forwardcharnext(), set))
                    {
                        Backwardnext();
                        return(true);
                    }
                }
            }
            return(false);
        }