MSQL到PDO

Question

我收到此错误：

  

不推荐使用：mysql_connect（）：不推荐使用mysql扩展，将来会删除它：使用mysqli或PDO代替。

我现在还没有使用PDO。

感谢您提供有关如何将MySQL迁移到PDO的任何帮助。

我的PHP代码如下：

//Set the database connection
mysql_connect('localhost','root','chethan');
mysql_select_db('menu');
//select all rows from the main_menu table
$result = mysql_query("select id,title,parentid,link from main_menu");

//create a multidimensional array to hold a list of menu and parent menu
$menu = array(
    'menus' => array(),
    'parent_menus' => array()
);

//build the array lists with data from the menu table
while ($row = mysql_fetch_assoc($result)) {
    //creates entry into menus array with current menu id ie. $menus['menus'][1]
    $menu['menus'][$row['id']] = $row;
    //creates entry into parent_menus array. parent_menus array contains a list of all menus with children
    $menu['parent_menus'][$row['parentid']][] = $row['id'];
}

// Create the main function to build milti-level menu. It is a recursive function.  
function buildMenu($parent, $menu) {
$html = "";
if (isset($menu['parent_menus'][$parent])) {
    $html .= "<ul>";
    foreach ($menu['parent_menus'][$parent] as $menu_id) {
        if (!isset($menu['parent_menus'][$menu_id])) {
            $html .= "<li><a href='" . $menu['menus'][$menu_id]['link'] . "'>" . $menu['menus'][$menu_id]['title'] . "</a></li>";
        }
        if (isset($menu['parent_menus'][$menu_id])) {
            $html .= "<li><a href='" . $menu['menus'][$menu_id]['link'] . "'>" . $menu['menus'][$menu_id]['title'] . "</a>";
            $html .= buildMenu($menu_id, $menu);
            $html .= "</li>";
        }
    }
    $html .= "</ul>";
}
return $html;

}