Regex match entire words only

regex word-boundary
Aaron picture Aaron · Nov 17, 2009 · Viewed 288k times · Source

I have a regex expression that I'm using to find all the words in a given block of content, case insensitive, that are contained in a glossary stored in a database. Here's my pattern:

/($word)/i

The problem is, if I use /(Foo)/i then words like Food get matched. There needs to be whitespace or a word boundary on both sides of the word.

How can I modify my expression to match only the word Foo when it is a word at the beginning, middle, or end of a sentence?

Answer

Richard Simões picture Richard Simões · Nov 17, 2009

Use word boundaries:

/\b($word)\b/i

Or if you're searching for "S.P.E.C.T.R.E." like in Sinan Ünür's example:

/(?:\W|^)(\Q$word\E)(?:\W|$)/i

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