PHP function to check whether all elements from one array are present in another array.

array_in_array.php

<?php
/**
 * Check whether all elements from $needle array are present in $haystack array.
 * Works for single-dimentional arrays only.
 * If you use multi-dimentional arrays, result could be misterious.
 * @param array $needle
 * @param array $haystack
 * @return boolean true if all elements in $needle are found in $haystack. false otherwise.
 */
function array_in_array($needle, $haystack) {
	return (count($needle) == count(array_intersect($needle, $haystack)));
}

// example
$needle = array(1, 2, null, "abc", 4.5);
$haystack = array(null, null, 4, 5, "a", "b", "c", 6, 3, 8, 2, 1, 0, "bca", "abc", 9/2);
var_dump(array_in_array($needle, $haystack));
?>