PHP: split function - Split string into array by regular expression

Description

array split ( string $pattern , string $string [, int $limit ] )

Splits a string into array by regular expression.

Parameters

pattern

Case sensitive regular expression.

If you want to split on any of the characters which are considered special by regular expressions, you'll need to escape them first. If you think split() (or any other regex function, for that matter) is doing something weird, please read the file regex.7, included in the regex/ subdirectory of the PHP distribution. It's in manpage format, so you'll want to do something along the lines of man /usr/local/src/regex/regex.7 in order to read it.

string

The input string.

limit

If limit is set, the returned array will contain a maximum of limit elements with the last element containing the whole rest of string .

Return Values

Returns an array of strings, each of which is a substring of string formed by splitting it on boundaries formed by the case-sensitive regular expression pattern .

If there are n occurrences of pattern , the returned array will contain n+1 items. For example, if there is no occurrence of pattern , an array with only one element will be returned. Of course, this is also true if string is empty. If an error occurs, split() returns FALSE.

Examples

Example #1 split() example

To split off the first four fields from a line from /etc/passwd:


<?php
list($user, $pass, $uid, $gid, $extra) =
    split(":", $passwd_line, 5);
?>

Example #2 split() example

To parse a date which may be delimited with slashes, dots, or hyphens:


<?php
// Delimiters may be slash, dot, or hyphen
$date = "04/30/1973";
list($month, $day, $year) = split('[/.-]', $date);
echo "Month: $month; Day: $day; Year: $year<br />\n";
?>

Notes

Tip

preg_split(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to split(). If you don't require the power of regular expressions, it is faster to use explode(), which doesn't incur the overhead of the regular expression engine.