Note: preg_split(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to split().
Returns an array of strings, each of which is a substring of string formed by splitting it on boundaries formed by the regular expression pattern. If limit is set, the returned array will contain a maximum of limit elements with the last element containing the whole rest of string. If an error occurs, split() returns FALSE.
To split off the first four fields from a line from /etc/passwd:
Tip: If there are n occurences of pattern, the returned array will contain n+1 items. For example, if there is no occurence of pattern, an array with only one element will be returned. Of course, this is also true if string is emply.
To parse a date which may be delimited with slashes, dots, or hyphens:
Note that pattern is case-sensitive.
Note that 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.
For users looking for a way to emulate Perl's $chars = split('', $str) behaviour, please see the examples for preg_split().
Please note that pattern is a 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.
See also: preg_split(), spliti(), explode(), implode(), chunk_split() and wordwrap().