index.php

<?php
/* index.php */
class main_class
{
    private $test2;
    var $test = "Hello<br />";
    public function __construct()
    {
        echo "Construct of 'main_class' called!<br />";
        $this->test2 = array();
        include("./test1.php");
        $this->test = new test1();
    }

    protected function do_include()
    {
        echo "Function 'do_include' called!<br />";
        include("./test2.php");
        $this->test2["test2"] = new test2();
    }
}

$test = new main_class();

?>