PHP设置PHPSESSID

Question

I am trying to set the PHPSESSID from a value I received from a CURL POST. However, it is not setting when I assign it to the session_id(). The first echo statement is the correct PHPSESSID from the curl post. However, the second echo returns empty. Any thoughts?

PHP

//set current session id
session_id($sessID[1]);
echo "current SessID: " . session_id();

//start session
session_start();
echo "PHPSESSID: " . $_COOKIE['PHPSESSID'];

Answer 1

PHP's superglobals are populated with data when the script starts up, and then they are NOT touched again by PHP for the life of the script. Your new session ID will only show up on the NEXT request, after the new session cookie's had a chance to round-trip through the client's browser.

Answer 2

You cannot echo anything before doing session_start() . Per the docs:

Note: To use cookie-based sessions, session_start() must be called before outputing anything to the browser.

http://us3.php.net//manual/en/function.session-start.php

The way you have it now is messing up the cookie. And you don't want to be messing up the cookies. :) The end result is the client never recognizes a session id cookie.