preg_match_all()

preg_match_all() — Perform a global regular expression match.

Built-in function of PHP 8.5. The manual lists it as available in PHP 4, PHP 5, PHP 7, PHP 8. This page is the reference card: signature, parameters and return value, plus the changelog and the example the manual provides.

What it does

Searches subject for all matches to the regular expression given in pattern and puts them in matches in the order specified by flags.

Signature

preg_match_all(string $pattern, string $subject, array &$matches = null, int $flags = 0, int $offset = 0): int|false

Parameters

Parameter	Type	What it takes
$pattern	string	The pattern to search for, as a string.
$subject	string	The input string.
&$matches	array	Array of all matches in multi-dimensional array ordered according to flags.
$flags	int	Can be a combination of the following flags (note that it doesn't make sense to use PREG_PATTERN_ORDER together with PREG_SET_ORDER): PREG_PATTERN_ORDER Orders results so that $matches[0] is an array of full pattern matches, $matches[1] is an array of strings matched by the first parenthesized subpattern, and so on. <?php preg_match_all("\|<[^>]+>(.*)</[^>]+>\|U", "<b>example: </b><div align=left>this is a ...
$offset	int	Normally, the search starts from the beginning of the subject string. The optional parameter offset can be used to specify the alternate place from which to start the search (in bytes).

Return value

Returns the number of full pattern matches (which might be zero), or false on failure.

Example

A runnable snippet:

preg_match_all("/$? (\d{3})? $? (?(1) [\-\s] ) \d{3}-\d{4}/x", "Call 555-1212 or 1-800-555-1212", $phones);

Changelog

Version	Change
7.2.0	The PREG_UNMATCHED_AS_NULL is now supported for the flags parameter.