Comparing two strings using preg_match

Question

I would like to search $string for occurrences of the contents of $array but am having trouble with the implode function returning the following:

preg_match(): Delimiter must not be alphanumeric or backslash

So in the example below $string will be searched for 'Empire' or 'Jedi'.

This is almost certainly something to do with escaping but I can't get my head round it.

Many thanks

$string = 'The Empire Strikes back';
$array = array (
        0 => 'Empire',
        1 => 'Jedi'
);

if (preg_match( implode(" ", $array), $string )) {
    echo "A match was found.";
} else {
    echo "A match was not found.";
}

possible duplicate of [Delimiter must not be alphanumeric or backslash and preg\_match](http://stackoverflow.com/questions/7660545/delimiter-must-not-be-alphanumeric-or-backslash-and-preg-match) — Toto, Sep 09 '14 at 07:36

score 1 · Answer 1 · answered Sep 08 '14 at 17:32

1

The correct : implode("|", $array)

Cause | = OR

answered Sep 08 '14 at 17:32

Cleiton Souza

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score 1 · Accepted Answer · answered Sep 08 '14 at 17:32

1

A regex must have delimiters. What you want is /Empire|Jedi/i (read: “search for Empire or Jedi, case insensitive”).

Therefore, you must use it as follows:

...
preg_match('/' . implode("|", $array) . '/', $string)
...

answered Sep 08 '14 at 17:32

lxg

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score 1 · Answer 3 · answered Sep 08 '14 at 17:32

1

$string = 'The Empire Strikes back';
$array = array (
        0 => 'Empire',
        1 => 'Jedi'
);

$re = join ('|', array_map('preg_quote', $array));
var_dump (preg_match ("/$re/", $string));

answered Sep 08 '14 at 17:32

akond

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anik4e · Answer 4 · 2014-09-08T17:41:12.030

0

You Can use this:

 $Words = array('Empire', 'Jedi');
 $strings = 'The Empire Strikes back';
 foreach ($Words as $Word) {
 if (preg_match("/\b$Word\b/", $strings)) {
     echo "A match was found.";
   }
  else{
    echo "A match was not found.";
   }
  }

edited Sep 08 '14 at 17:41

answered Sep 08 '14 at 17:35

anik4e

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Comparing two strings using preg_match

4 Answers4