Before reading this answer, you should be familiar with the mechanism of backtracking, atomic groups, and possessive quantifiers. You can find information about these notions and features in the Friedl book and following these links: www.regular-expressions.info, www.rexegg.com All the test has been made with a global search (with the preg_match_all() function). (*FAIL) (or the shorthand … Read more
PCRE does not support the \uXXXX syntax. Use \x{XXXX} instead. See here. Your \u2e80-\u9fff range is also equivalent to \p{InCJK_Radicals_Supplement}\p{InKangxi_Radicals}\p{InIdeographic_Description_Characters}\p{InCJK_Symbols_and_Punctuation}\p{InHiragana}\p{InKatakana}\p{InBopomofo}\p{InHangul_Compatibility_Jamo}\p{InKanbun}\p{InBopomofo_Extended}\p{InKatakana_Phonetic_Extensions}\p{InEnclosed_CJK_Letters_and_Months}\p{InCJK_Compatibility}\p{InCJK_Unified_Ideographs_Extension_A}\p{InYijing_Hexagram_Symbols}\p{InCJK_Unified_Ideographs} Don’t forget to add the u modifier (/regex here/u) if you’re dealing with UTF-8. If you’re dealing with another multi-byte encoding, you must first convert it to UTF-8.
Answer to question 1 To answer the first question one could use: (?xm) # ignore comments and whitespace, ^ matches beginning of line ^ # beginning of line (?: . # any character except \n (?= # lookahead .*+\n # go to next line ( \1?+ . ) # add a character to the 1st … Read more
You buy RegexBuddy and use its built in debug feature. If you work with regexes more than twice a year, you will make this money back in time saved in no time. RegexBuddy will also help you to create simple and complex regular expressions, and even generate the code for you in a variety of … Read more
You can use an assertion for that, as you just have to ensure that the searched words occur somewhen after an >, or before any <. The latter test is easier to accomplish as lookahead assertions can be variable length: /(asf|foo|barr)(?=[^>]*(<|$))/ See also http://www.regular-expressions.info/lookaround.html for a nice explanation of that assertion syntax.
Although the u modifier makes both the pattern and subject be interpreted as UTF-8, the captured offsets are still counted in bytes. You can use mb_strlen to get the length in UTF-8 characters rather than bytes: $str = “\xC2\xA1Hola!”; preg_match(‘/H/u’, $str, $a_matches, PREG_OFFSET_CAPTURE); echo mb_strlen(substr($str, 0, $a_matches[0][1]));
The biggest change in the syntax is the addition of delimiters. ereg(‘^hello’, $str); preg_match(‘/^hello/’, $str); Delimiters can be pretty much anything that is not alpha-numeric, a backslash or a whitespace character. The most used are generally ~, / and #. You can also use matching brackets: preg_match(‘[^hello]’, $str); preg_match(‘(^hello)’, $str); preg_match(‘{^hello}’, $str); // etc If … Read more
PHP regex strings need delimiters. Try: $numpattern=”/^([0-9]+)$/”; Also, note that you have a lower case o, not a zero. In addition, if you’re just validating, you don’t need the capturing group, and can simplify the regex to /^\d+$/. Example: http://ideone.com/Ec3zh See also: PHP – Delimiters
I think the problem is much simpler than that: You forgot to specify the u modifier. The Unicode character properties are only available in UTF-8 mode. Your regex should be: // unicode letters, apostrophe, hyphen, space $namePattern = ‘/^[-\’ \p{L}]+$/u’;
Neither basic nor extended Posix/GNU regex recognizes the non-greedy quantifier; you need a later regex. Fortunately, Perl regex for this context is pretty easy to get: perl -pe ‘s|(http://.*?/).*|\1|’