<?php
class test {
	var $filter = 'hello'; 
	var $array = array('hello', 'hello world', 'hey there');
	
	function test() {
		array_filter($this->array, array($this, 'filter'));
	}
	
	function filter ($value) {
		return preg_match("/{$this->filter}/i", $value);
	}
}
$t = new test;
var_dump($t->filter('hello world'));
?>