Answer by Casper Wilkes for How to check if multiple array keys exists

This is old and will probably get buried, but this is my attempt.

I had an issue similar to @Ryan. In some cases, I needed to only check if at least 1 key was in an array, and in some cases, all needed to be present.

So I wrote this function:

/** * A key check of an array of keys * @param array $keys_to_check An array of keys to check * @param array $array_to_check The array to check against * @param bool $strict Checks that all $keys_to_check are in $array_to_check | Default: false * @return bool */function array_keys_exist(array $keys_to_check, array $array_to_check, $strict = false) {    // Results to pass back //    $results = false;    // If all keys are expected //    if ($strict) {        // Strict check //        // Keys to check count //        $ktc = count($keys_to_check);        // Array to check count //        $atc = count(array_intersect($keys_to_check, array_keys($array_to_check)));        // Compare all //        if ($ktc === $atc) {            $results = true;        }    } else {        // Loose check - to see if some keys exist //        // Loop through all keys to check //        foreach ($keys_to_check as $ktc) {            // Check if key exists in array to check //            if (array_key_exists($ktc, $array_to_check)) {                $results = true;                // We found at least one, break loop //                break;            }        }    }    return $results;}

This was a lot easier than having to write multiple || and && blocks.