PHP将对象转换成数组的方法,兼容多维数组类型

/** 
* @author gayayang 
* @date 2012-8-21 
* @todo 将对象转换成数组 
* @param unknown_type $obj 
* @return unknown 
*/ 
function object_to_array($obj){ 
    $_arr = is_object($obj) ? get_object_vars($obj) :$obj; 
    foreach ($_arr as $key=>$val){ 
      $val = (is_array($val) || is_object($val)) ? $this->object_to_array($val):$val; 
      $arr[$key] = $val; 
  } 
    return $arr; 
}