public function shuffle_assoc($list) {   
	if (!is_array($list)) return $list;   
	$keys = array_keys($list);   
	shuffle($keys);   
	$random = array();   
	foreach ($keys as $key)   
	    $random[$key] = $list[$key];   
	    return $random;   
	} 

函数：二维数组打乱顺序