(PHP 4, PHP 5, PHP 7, PHP 8)
preg_split — Split string by a regular expression
Split the given string by a regular expression.
patternThe pattern to search for, as a string.
subjectThe 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 or 0 means "no limit".
flags
flags can be any combination of the following
flags (combined with the | bitwise operator):
PREG_SPLIT_NO_EMPTYPREG_SPLIT_DELIM_CAPTUREPREG_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, or false on failure.
If the regex pattern passed does not compile to a valid regex, an E_WARNING is emitted.
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.