Online PHP editor | refs for YFpZc

<?php class MenuElement { public $id; public $children = array(); public function __construct($id) { $this->id = $id; } public function addChild(MenuElement $menuElement) { array_push($this->children, $menuElement); } } $menuElement1 = new MenuElement(1); $menuElement11 = new MenuElement(11); $menuElement12 = new MenuElement(12); $menuElement121 = new MenuElement(121); $menuElement122 = new MenuElement(122); $menuElement123 = new MenuElement(123); $menuElement1211 = new MenuElement(1211); $menuElement121->addChild($menuElement1211); $menuElement12->addChild($menuElement121); $menuElement12->addChild($menuElement122); $menuElement12->addChild($menuElement123); $menuElement1->addChild($menuElement11); $menuElement1->addChild($menuElement12); function foo(MenuElement $elt, $level = 0) { if (0 == $level) echo '<ul>'.PHP_EOL; echo str_repeat(' ', $level+1).'<li>'.$elt->id; if (!count($elt->children)) { echo '</li>'.PHP_EOL; return; } echo PHP_EOL.str_repeat(' ', $level+2).'<ul>'.PHP_EOL; foreach($elt->children as $child) foo($child, $level+2); echo str_repeat(' ', $level+2).'</ul>'.PHP_EOL; echo str_repeat(' ', $level+1).'</li>'.PHP_EOL; if (0 == $level) echo '</ul>'.PHP_EOL; } foo($menuElement1);