WordPress WP_User_Query Transient Array Search

gistfile1.php

<?php
/*
 * WordPress WP_User_Query Transient Array Search
 *
 * Purpose: To search array of relevant user fields
 * stored as an array in a transient
 *
 * Example Array:
 * [userid] => array (
      '0' => 'first_name',
      '1' => 'last_name',
      '2' => 'custom_id'
      )
 *
 * @param array $array Input array to search for values
 * @param array $search Passed array is created prior to function by an explode(' ', $user_entered_term)
 *
 * @return array userid for each match
 */
 
function sd_student_search($array, $search) {
	// Est. array with dummy value (better way??)
	// Otherwise WP_User_Query will include everyone instead of no one when no values found
	$found = array('prevent_show_all');
	
	// Define $search as array if input as string
	if(!is_array($search))
		$search = array($search);
	
	foreach($search as $term) {
		$term = strtolower($term);
		
		foreach($array as $key => $values) {
			foreach($values as $index => $data) {
				$data = strtolower($data);
				if( strpos($data, $term) !== FALSE )  {
					$found[] = $key;
				}
			}
		}
	}
	
	return $found;
}
?>