PHP: preg_grep function - Return array entries that match the pattern

array preg_grep ( string $pattern , array $input [, int $flags ] )

Returns the array consisting of the elements of the input array that match the given pattern .

pattern: The pattern to search for, as a string.
input: The input array.
flags: If set to PREG_GREP_INVERT, this function returns the elements of the input array that do not match the given pattern .

Returns an array indexed using the keys from the input array.

Version Description

4.2.0 The flags parameter was added.

4.0.4

Prior to this version, the returned array was indexed regardless of the keys of the input array.

If you want to reproduce this old behavior, use array_values() on the returned array to reindex the values.

Example #1 preg_grep() example


<?php
// return all array elements
// containing floating point numbers
$fl_array = preg_grep("/^(\d+)?\.\d+$/", $array);
?>