[PHP錯誤訊息] Notice: A session had already been started - ignoring session_st

JDP

錯誤訊息:
Notice: A session had already been started - ignoring session_start() in D:\httpd\www\xxxx.php on line x

解決辦法:
將原本的
session_start();
改成
if (!isset($_SESSION)) {<br />     session_start();<br /> }