PHP preg_match to find whole words

php preg-match
tintix picture tintix · Jan 18, 2011 · Viewed 44.1k times · Source

I'm quite new to regular expressions. Could you help me to create a pattern, which matches whole words, containing specific part? For example, if I have a text string "Perform a regular expression match" and if I search for express, it shuld give me expression, if I search for form, it should give me Perform and so on. Got the idea?

Answer

Linus Kleen picture Linus Kleen · Jan 18, 2011 
preg_match('/\b(express\w+)\b/', $string, $matches); // matches expression
preg_match('/\b(\w*form\w*)\b/', $string, $matches); // matches perform,
                                                     // formation, unformatted

Where:

  • \b is a word boundary
  • \w+ is one or more "word" character*
  • \w* is zero or more "word" characters

See the manual on escape sequences for PCRE.

* Note: although not really a "word character", the underscore _ is also included int the character class \w.

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