Regex for capturing specific values in PHP

Question

I trying to get the values from a string by a regular expression pattern, it works, but it will return all matched strings (I mean the string with {} too)

this is the string:

dashboard/admin/{content}/category/{category}/posts

Regex pattern:

/{(.*?)}/

and the PHP code is :

    preg_match_all('/{(.*?)}/', $url, $matches, PREG_SET_ORDER, 0);

and the content of $matches is:

array:2 [
  0 => array:2 [
    0 => "{content}"
    1 => "content"
  ]
  1 => array:2 [
    0 => "{category}"
    1 => "category"
  ]
]

but I want to have an array like this:

array:2 [
  0 => "content",
  1 => "category"
]

Answer 1

Use lookaround:

$url = 'dashboard/admin/{content}/category/{category}/posts';
preg_match_all('/(?<={).*?(?=})/', $url, $matches, PREG_SET_ORDER, 0);
print_r($matches);

Output:

Array
(
    [0] => Array
        (
            [0] => content
        )

    [1] => Array
        (
            [0] => category
        )

)