CODEWITHSUNDEEP
phppreg-match
Michalis
Michalis

Reputation: 6926

How to Exclude Phrases to preg_match

I have this text and I want to search the word "job" except the phrase "on the job training" or a list of phrases. If I use this preg_match http://regexr.com/3dlo7

I get 3 results... but I want only the 1st and the 3rd

This is a good job and this is on the job training. Nice job

Any ideas for the preg_match?

Upvotes: 0

Views: 1202

Answers (3)

Ravi Hirani
Ravi Hirani

Reputation: 6539

Use this regex:-

\bjob(?!\straining)\b

http://regexr.com/3dloj

After your comment you also want to exclude word before your word then use below regex:-

\b(?<!Nice\s)job(?!\straining)\b  // exclude Nice word

http://www.phpliveregex.com/p/g8h

(?<!Nice\s)job matches Nice "job" that is not preceded by an "Nice ", using negative lookbehind.

Upvotes: 0

Casimir et Hippolyte
Casimir et Hippolyte

Reputation: 89547

First, when you want to test a regex for PHP, don't use RegExr that is designed for Javascript, you can use instead regex101.com or regex.larsolavtorvik.com

You can design your pattern like this:

\bjob\b(?!(?<=\bon the job) training\b)

and if you want to exclude other cases:

\bjob\b(?!(?<=\bon the job) training\b|(?<=\bthe job) I hate\b)

You can also use a (*SKIP)(*F) pattern (that makes the subpattern to fail and forces characters already matched to be skipped), it can be more easy to write but it's less efficient (due to the fact that the pattern has an alternation at the beginning):

\b(?:on the job training\b(*SKIP)(*F)|the job I hate\b(*SKIP)(*F)|job\b)

You can improve it a little using the first character discrimination trick to quickly fail on non-interesting positions:

\b(?=[otj])(?:on the job training\b(*SKIP)(*F)|the job I hate\b(*SKIP)(*F)|job\b)

Upvotes: 3

Toto
Toto

Reputation: 91385

How about using lookaround:

$str = 'This is a good job and this is on the job training. Nice job';
preg_match_all('/(?<!on the )\bjob\b(?! training)/', $str, $m);
print_r($m);

Output:

Array
(
    [0] => Array
        (
            [0] => job
            [1] => job
        )

)

Upvotes: 1

Related Questions