php使用amf3与flex通讯，所有内容都要写在类和类的函数中么，require(/includes/sq_init.php)不支持么？全局变量也不可以用？

<?phprequire('/includes/init.php');    //这行好像不行class HelloWorld{  public function sayHelloWorld($value) {   $GLOBALS['db'] ;     //这行好像也不行啊  echo $value;  return " AMF-RPC for PHP".$value;  }}?>

<?phpdefine('ROOT_PATH', str_replace('amfphp-2.1.1/Amfphp/Services/HelloWorld.php', '', str_replace('\\', '/', __FILE__)));require(ROOT_PATH . '/includes/sq_init.php'); class HelloWorld{  public function sayHelloWorld($value)  {   GLOBALS $db ;   echo $value;   return " AMF-RPC for PHP".$value;  }}?>

<?php/**2013-12-01 */if (!defined('IN_ECS')){    die('Hacking attempt');}/* 取得当前ecshop所在的根目录 */define('ROOT_PATH', str_replace('includes/sq_init.php', '', str_replace('\\', '/', __FILE__)));/* 初始化设置 */@ini_set('memory_limit',          '64M');@ini_set('session.cache_expire',  180);@ini_set('session.use_trans_sid', 0);@ini_set('session.use_cookies',   1);@ini_set('session.auto_start',    0);@ini_set('display_errors',        1);if (DIRECTORY_SEPARATOR == '\\'){    @ini_set('include_path', '.;' . ROOT_PATH);}else{    @ini_set('include_path', '.:' . ROOT_PATH);}require(ROOT_PATH . 'data/config.php');require(ROOT_PATH . 'includes/inc_constant.php');require(ROOT_PATH . 'includes/cls_ecshop.php');require(ROOT_PATH . 'includes/lib_base.php');/* 创建 ECSHOP 对象 */$ecs = new ECS($db_name, $prefix);define('DATA_DIR', $ecs->data_dir());define('IMAGE_DIR', $ecs->image_dir());/* 初始化数据库类 */require(ROOT_PATH . 'includes/cls_mysql.php');$db = new cls_mysql($db_host, $db_user, $db_pass, $db_name);$db->set_disable_cache_tables(array($ecs->table('sessions'), $ecs->table('sessions_data'), $ecs->table('cart')));$db_host = $db_user = $db_pass = $db_name = NULL;?>