Question

This is the first array:

$possible_combinations = array(
    1 => array(1),
    2 => array(2),
    3 => array(3),
    4 => array(4),

    5 => array(1, 2),
    6 => array(1, 3),
    7 => array(1, 4),       

    8 => array(2, 3),
    9 => array(2, 4),       

    10 => array(3, 4),

    11 => array(2, 3, 4),
    12 => array(1, 3, 4),
    13 => array(1, 2, 4),
    14 => array(1, 2, 3),

    15 => array(1, 2, 3, 4)
);

This is the second array:

$seeking = array(2, 3, 4);

As you can see $possible_combinations[11] matches $seeking.

The value of $seeking in this case is 2, 3, 4 but it may be different at other times. How can I run a check against the
$possible_combinations array to see if the $seeking array matches any of the values of that associative array.
It should return the key of the match if there is one.

Answer 1

You can use PHP’s built-in array_search() function for this.

$search = array_search($seeking,$possible_combinations);

if ($search !== FALSE) {
    echo 'Found at ' . $search;
} else {
    echo 'Not Found';
}

http://www.php.net/manual/en/function.array-search.php