(PHP 4, PHP 5)
preg_split — Split string by a regular expression
$pattern
, string $subject
[, int $limit
= -1
[, int $flags
= 0
]] )Split the given string by a regular expression.
pattern
The pattern to search for, as a string.
subject
The input string.
limit
If specified, then only substrings up to limit
are returned with the rest of the string being placed in the last
substring. A limit
of -1, 0 or NULL
means "no limit"
and, as is standard across PHP, you can use NULL
to skip to the
flags
parameter.
flags
flags
can be any combination of the following
flags (combined with the | bitwise operator):
PREG_SPLIT_NO_EMPTY
PREG_SPLIT_DELIM_CAPTURE
PREG_SPLIT_OFFSET_CAPTURE
If this flag is set, for every occurring match the appendant string
offset will also be returned. Note that this changes the return
value in an array where every element is an array consisting of the
matched string at offset 0 and its string offset
into subject
at offset 1.
Returns an array containing substrings of subject
split along boundaries matched by pattern
.
Example #1 preg_split() example : Get the parts of a search string
<?php
// split the phrase by any number of commas or space characters,
// which include " ", \r, \t, \n and \f
$keywords = preg_split("/[\s,]+/", "hypertext language, programming");
print_r($keywords);
?>
The above example will output:
Array ( [0] => hypertext [1] => language [2] => programming )
Example #2 Splitting a string into component characters
<?php
$str = 'string';
$chars = preg_split('//', $str, -1, PREG_SPLIT_NO_EMPTY);
print_r($chars);
?>
The above example will output:
Array ( [0] => s [1] => t [2] => r [3] => i [4] => n [5] => g )
Example #3 Splitting a string into matches and their offsets
<?php
$str = 'hypertext language programming';
$chars = preg_split('/ /', $str, -1, PREG_SPLIT_OFFSET_CAPTURE);
print_r($chars);
?>
The above example will output:
Array ( [0] => Array ( [0] => hypertext [1] => 0 ) [1] => Array ( [0] => language [1] => 10 ) [2] => Array ( [0] => programming [1] => 19 ) )
If you don't need the power of regular expressions, you can choose faster (albeit simpler) alternatives like explode() or str_split().
If matching fails, an array with a single element containing the input string will be returned.