Consider the following string and Regex:
$string = 'xxx-zzzzzz-xxx';
preg_match('/(?<=xxx-)(.*)(?=-xxx)/', $string, $extract);
var_dump($extract);
This outputs:
array (size=2)
0 => string 'zzzzzz' (length=6)
1 => string 'zzzzzz' (length=6)
Why do I get an array size of 2 since the matched string only appears once? And how would I do to get only a string or an array with 1 string? Thanks in advance.
index=0 is whole match and index=1 (and onwards) is first captured group. If you don't want captured group then just use:
/(?<=xxx-).*(?=-xxx)/
i.e.
preg_match('/(?<=xxx-).*(?=-xxx)/', $string, $extract);
print_r($extract);
From the PHP Manual:
If
$matchesis provided, then it is filled with the results of search.$matches[0]will contain the text that matched the full pattern,$matches[1]will have the text that matched the first captured parenthesized subpattern, and so on.
In other words, matches[0] returns the full match, with other keys in the array returning only partial matches (equal to the number of () used in your regular expression).
Keep in mind that preg_match will only ever match one complete result; if you want to return all matches in a given string, have a look at preg_match_all() instead.
