以下是登录网站异常的信息，还请高手给予快速解答原因：
Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\wp-content\themes\blog-moban\functions.php:13) in C:\xampp\htdocs\wp-includes\pluggable.php on line 1178
header之前不能有输出。。
