How can use session in php

This data will be available to all pages on the site during that visit. The location of the temporary file is determined by a setting in the php. Before using any session variable make sure you have setup this path. PHP first creates a unique identifier for that particular session which is a random string of 32 hexadecimal numbers such as 3c7foj34c3jjhjkop2fce When a PHP script wants to retrieve the value from a session variable, PHP automatically gets the unique session identifier string from the PHPSESSID cookie and then looks in its temporary directory for the file bearing that name and a validation can be done by comparing both values.

A session ends when the user loses the browser or after leaving the site, the server will terminate the session after a predetermined period of time, commonly 30 minutes duration.

This function first checks if a session is already started and if none is started then it starts one. These variables can be accessed during lifetime of a session. If there is a match, it accesses that session, if not, it starts a new session.

We just launched W3Schools videos. Get certified by completing a course today! If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail:. Exercise: Create a session variable named "favcolor". Report Error. Your message has been sent to W3Schools.

W3Schools is optimized for learning and training. Examples might be simplified to improve reading and learning. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. This function does not need any argument and a single call destroys all the session data. Every PHP session has a timeout value — a duration, measured in seconds — which determines how long a session should remain alive in the absence of any user activity.

You can adjust this timeout duration by changing the value of session. Is this website helpful to you? Please give us a like , or share your feedback to help us improve. Connect with us on Facebook and Twitter for the latest updates. Example Download. Previous Page Next Page.