PHP Capture string between characters

Question

What is the best way to capture a string between 2 certain characters in PHP? Looking online some people say to explode it, some suggest using str_ functions, some suggest regex,

:>Test!1.221ddba.0_31df0888d4d13e9456a2bdafc93437ff@~127.0.0.1 JOIN UUNN :%#Test

I wish to capture the string between the : and the !, i.e. >Test. How can I do this with a regex, or is there a simpler way?

`or is there a simpler way?` - asking here I guess qualifies as the simpler way. — Professor Abronsius, Jan 31 '19 at 08:19
Is the string containing only one ":" and one "!", or can they occure multiple times? — Gizzmo, Jan 31 '19 at 08:26
Possibly related question https://stackoverflow.com/questions/14059747/regex-to-match-everything-between-the-first-and-last-occurrence-of-two-distinct — Eugene Anisiutkin, Jan 31 '19 at 08:45
Also possibly related, although it is Java code https://stackoverflow.com/questions/49452796/regex-match-everything-between-two — Eugene Anisiutkin, Jan 31 '19 at 09:02

score 0 · Answer 1 · answered Jan 31 '19 at 08:19

0

here is the PHP with RegEx. Maybe it helps :)

$re = '/(?<=:).*(?=!)/';
$str = ':>Test!1.221ddba.0_31df0888d4d13e9456a2bdafc93437ff@~127.0.0.1 JOIN UUNN :%#Test';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);

Link to Regex101.com

answered Jan 31 '19 at 08:19

Sascha Walzenbach

159
7

This looks Greedy. It will also return wrong results if a string contains un-expected `:` and `!` symbols – Eugene Anisiutkin Jan 31 '19 at 09:44

Eugene Anisiutkin · Answer 2 · 2019-01-31T10:02:04.887

After some modifying the answers that i already found I came up with this RegEx

/(?<=:)[^:!]*(?=!)/miu

Regex explanation:

(?<=:) - Positive lookbehind ensuring what precedes matches : literally
[^:!]* - Matches any character except : and ! any number of times.
(?=!) - Positive lookahead ensuring what follows is ! literally.

A bit basic explanation

The above regex actually not only grabs every symbol between : and !, but also ensures, that between these two sybols there are no other occurenses of either : or !.
Actuall, it only maches text that is strictly between : and !. Everything else is not matched. If there is no : followed by a ! at all then the result will be empty.

This was tested using https://regex101.com/.

Php code generated for the test is

<?php
$re = '/(?<=:)[^:!]*(?=!)/m';
$str = ':ssuguwuug!jsgejjgjj!yhjyt:feeeeeg!uuuuuuu:uuuuu:uuu!';

preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);

// Print the first match result, since it looks like OP only wanted a first match 
var_dump($matches[0]);

?>

EDIT

I really tried to make it as un-Greedy as I could, but * is a Greedy Quantifier

PHP Capture string between characters

2 Answers2