5/27/2018 Php Regex Cheat Sheet

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PHP PCRE Cheat Sheet

Functions

preg_match(pattern, subject[, submatches])

preg_match_all(pattern, subject[, submatches])

preg_replace(pattern, replacement, subject)

preg_replace_callback(pattern, callback, subject)preg_grep(pattern, array)

preg_split(pattern, subject)

Base Character Classes

\w Any word character (a!" #!$ _)

\% Any non word character

\s %hitespace (space, tab &')

\* Any non whitepsace character

\d +igits (#!$)

\+ Any non digit character (-eriod) . Any character e/cept newlin

Meta Characters0 *tart o1 subject (or line in multiline mode)

2 3nd o1 subject (or line in multiline mode)

[ *tart character class de1inition

] 3nd character class de1inition

4 Alternates, eg (a4b) matches a or b( *tart subpattern) 3nd subpattern\ 3scape character

Quantifiers

n5 6ero or more o1 n

n7 8ne or more o1 n

n9 6ero or one occurrences o1 n

:n; n occurrences e/actly

:n,; At least n occurrences

:,m; At most m occurrences

:n,m; ultiline mode ! 0 and 2 match start andend o1 lines

s +otall ! class includes newline

/ 3/tended. comments ? whitespacee preg_replace only . enables e=aluation o1

replacement as -@- code* 3/tra analysis o1 pattern -attern is ungreedyu -attern is treated as B!C

Point based assertions

\b %ord boundary

\< Dot a word boundary

\A *tart o1 subject

\6 3nd o1 subject or newline at end

\" 3nd o1 subject\E irst matching position in subject

Subpattern Modifiers & Assertions

(9F) Don capturing subpattern ((9F1oo41u)bar) matches 1oobar or 1ubar without 1oo or 1uappearing as a captured subpattern

(9G) -ositi=e look ahead assertion 1oo(9Gbar) matches 1oo when 1ollowed by bar

(9H) Degati=e look ahead assertion 1oo(9Hbar) matches 1oo when not1ollowed by bar(9IG) -ositi=e look behind assertion (9IG1oo)bar matches bar when preceded by 1oo(9IH) Degati=e look behind assertion (9IH1oo)bar matches bar when notpreceded by 1oo(9J) 8nce!only subpatterns (9J\d7)bar -er1ormance enhancing when bar not present(9(/)) &onditional subpatterns (9(K)1oo41u)bar >atches 1oo i1 Krdsubpattern has matched, 1u (9L) &omment (9L -attern does / y or ")

5/27/2018 Php Regex Cheat Sheet

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