private static IList <IOccurrence> StringOccurrences(string text, string pattern)
{
// Loop through all instances of the string 'text'.
IList <IOccurrence> occurrences = new Occurrences();
int i = 0;
while ((i = text.IndexOf(pattern, i)) != -1)
{
occurrences.Add(new Occurrence(i, i + pattern.Length));
i += pattern.Length;
}
return(occurrences);
}
private static Occurrences ExceptionMatches(string input, IList <Expression> exceptions)
{
Occurrences exceptionMatches = new Occurrences();
if (exceptions == null || (exceptions.Count == 0))
{
return(exceptionMatches);
}
foreach (Expression exception in exceptions)
{
foreach (Occurrence pointer in exception.Occurrences(input))
{
exceptionMatches.Add(pointer);
}
}
return(exceptionMatches);
}
/// <summary>
/// Pointers to start indexes in the input, where patterns starts.
/// </summary>
/// <param name="input">Input text in which the pattern is searched.</param>
/// <returns>List of integers. If there is no pattern match, empty list is returned.</returns>
// při porovnánání výjimky se pak zjišťuje, jestli výskyt je mezi těmito krajními body
public IList <IOccurrence> Occurrences(string input)
{
IList <IOccurrence> occurences = new Occurrences();
switch (Format)
{
case ChangeFormat.String:
occurences = StringOccurrences(input, Pattern);
break;
case ChangeFormat.RegularExpression:
MatchCollection matches = _regex.Matches(input);
foreach (Match match in matches)
{
occurences.Add(new Occurrence(match.Index, match.Index + match.Length));
}
break;
default:
throw new ArgumentOutOfRangeException();
}
return(occurences);
}
