Using array_diff for broad matches?

Question

What I'm trying to do is take items from one array, such as:

$array1 = array(
"google-com",
"youtube-com",
);

And remove items from a second array if the above items are included (but BROAD match, not exact).

$array2 = array(
"www-google-com",
"www-youtube-com",
"www-facebook-com",
"www-twitter-com",
);

Expected output:

 www-facebook-com
 www-twitter-com

Note: The first array would be with "example.com" style URLs and the second with "https://www.example.com/" URLs.

It seems array_diff only works with exact matches, and after much searching, I can't seem to find a way to make it work for broad matches.

Thanks for your help!

Answer 1

You're right, array_diff is not a solution here. One of the solutions is using a preg_grep to find records and then unset keys in $array2:

$array1 = array(
    "google-com",
    "youtube-com",
);

$array2 = array(
    "www-google-com",
    "www-youtube-com",
    "www-facebook-com",
    "www-twitter-com",
);

foreach ($array1 as $search) {
    foreach (preg_grep('/' . $search . '/', $array2) as $index => $value) {
        unset($array2[$index]);
    }
}

print_r($array2);