在PHP中获取两个字符之间的字符串

Question

I have a string in php say

$string = 'All I want to say is that <#they dont really care#> about us.
    I am wasted away <#I made a million mistake#>, am I too late. 
    Theres a storm in my head and a race on my bed, <#when you are not near#>' ;


$expected_output = array(
    'they dont really care',
    'I made a million mistake',
    'when you are not near'
);

How can I acheive this using PHP regex ? Thanks for reading :)

Answer 1

This code will do what you want

<?php

$string = 'All I want to say is that <#they dont really care#> about us.
    I am wasted away <#I made a million mistake#>, am I too late. 
    Theres a storm in my head and a race on my bed, <#when you are not near#>' ;


preg_match_all('/<#(.*)#>/isU', $string, $matches);

var_dump($matches[1]);

Answer 2

You can use this regex:

'/<#(.*?)#>/s'

in preg_match_all function call.

I don't want to give you full code but this should be good enough to get you going.

Answer 3

Through lookahead and lookbehind,

(?<=<#).*?(?=#>)

Finally call preg_match_all function to print the matched strings.

Your PHP code would be,

<?php
$data = 'All I want to say is that <#they dont really care#> about us.
    I am wasted away <#I made a million mistake#>, am I too late. 
    Theres a storm in my head and a race on my bed, <#when you are not near#>' ;
$regex =  '~(?<=<#).*?(?=#>)~';
preg_match_all($regex, $data, $matches);
var_dump($matches);
?>

Output:

array(1) {
  [0]=>
  array(3) {
    [0]=>
    string(21) "they dont really care"
    [1]=>
    string(24) "I made a million mistake"
    [2]=>
    string(21) "when you are not near"
  }
}

Answer 4

A more compact version:

$regex = '~<#\K.*?(?=#>)~';
preg_match_all($regex, $string, $matches);
print_r($matches[0]);

See the matches in the regex demo .

Matches

they dont really care
I made a million mistake
when you are not near

Explanation

• The ^ anchor asserts that we are at the beginning of the string
• <# matches the left delimiter
• The \\K tells the engine to drop what was matched so far from the final match it returns
• .*? lazily matches chars up to the point where...
• The lookahead (?=#>) can assert that what follows is #>
• The $ anchor asserts that we are at the end of the string

Reference

• Lookahead and Lookbehind Zero-Length Assertions
• Mastering Lookahead and Lookbehind