Question

I would like to get strings inside [square] [brackets] and also those @like @this. The following works for the [tags] but not the @users.

$query = "[tag1] [tag2] @user1 @user2 ignoreme";

// check for tags e.g. [tag1] [tag2]
preg_match_all("/\[([^\]]+)\]/", $query, $tags);

// check for users e.g. @username
preg_match_all("/\B@[^\B]+/", $query, $users);

print_r($tags);
print_r($users);

Output:

(
    [0] => Array
        (
            [0] => [tag1]
            [1] => [tag2]
        )
        [1] => Array
        (
            [0] => tag1
            [1] => tag2
        )
    )
Array
(
    [0] => Array
        (
            [0] => @user1 @user2 ignoreme
        )
    )

The tag preg_match is working but the @user one just grabs everything after it (even ignoring the second @user2).

Answer 1

If you look at this explanation: http://regex101.com/r/fH4lG4 you’ll find out why your regex is broken.

You’re matching everything BUT the literal B.

What you should be doing is either [^@]+, [^@ ]+ or \S+

I hope this helps 🙂