动态菜单不会在线显示，但它在netbeans中显示

this is a piece of the php file

 <div id='cssmenu' >

                <?php
                include '/include/functions.php';
               echo BuildMenu(0, Menu());
                ?>
            </div>    

And these or the two functions in the functions.php

    function Menu() {

    $con = getConnection();

    $menu = array(
        'items' => array(),
        'parents' => array()
    );$result = mysqli_query($con, "SELECT id,title,link,parentid FROM dyn_menu ORDER BY id;");
          while ($items = mysqli_fetch_assoc($result)) {

            $menu['items'][$items['id']] = $items;

            $menu['parents'][$items['parentid']][] = $items['id'];
        }
        mysqli_free_result($result);

    mysqli_close($con);

    return $menu;
}

    function BuildMenu($begin, $menu) {
    $html = "";
    if (isset($menu['parents'][$begin])) {
        $html .= "<ul>
";
        foreach ($menu['parents'][$begin] as $itemId) {


            if (!isset($menu['parents'][$itemId])) {
                $html .= "<li>
  <a href='" . $menu['items'][$itemId]['link'] . "'>" . $menu['items'][$itemId]['title'] . "</a>
</li> 
";
            } 

            if (isset($menu['parents'][$itemId])) {

                $html .= "<li>
  <a href='" . $menu['items'][$itemId]['link'] . "'>" . $menu['items'][$itemId]['title'] . "</a> 
";
                $html .= BuildMenu($itemId, $menu);
                $html .= "</li> 
";
            } 

        }
        $html .= "</ul> 
";
    }
    return $html;
}

The php file doesn't show the generated html that the php script should provide, in a live enviroment, but it does in netbeans. And i don't know why or how i can resolve this issue.