How to check if multiple array keys exists

Question

I have a variety of arrays that will either contain

story & message

or just

story

How would I check

Answer 1

If you only have 2 keys to check (like in the original question), it's probably easy enough to just call array_key_exists() twice to check if the keys exists.

if (array_key_exists("story", $arr) && array_key_exists("message", $arr)) {
    // Both keys exist.
}

However this obviously doesn't scale up well to many keys. In that situation a custom function would help.

function array_keys_exists(array $keys, array $arr) {
   return !array_diff_key(array_flip($keys), $arr);
}