Hour 16. Working with User Sessions

In Hour 15, "Restricting Access to Your Applications," we looked at using cookies to store user-related values, but once again, PHP is one step ahead of us. PHP contains numerous functions for managing user sessions, which can be stored in the $_SESSION superglobal. Sessions use techniques similar to those explored in the preceding hour but build them into the language; thus, saving state is as easy as calling a function.

In this hour, you will learn

What session variables are and how they work
How to start or resume a session
How to store variables in a session
How to destroy a session
How to unset session variables

Part II: Basic Language Elements

Part III: Getting Involved with the Code

Hour 9. Working with Forms

Hour 10. Working with Files

Hour 11. Working with Dates and Times

Hour 12. Creating a Simple Calendar

Hour 13. Working with Strings

Hour 14. Creating a Simple Discussion Forum

Hour 15. Restricting Access to Your Applications

Hour 16. Working with User Sessions

Session Function Overview

Starting a Session

Working with Session Variables

Passing Session IDs in the Query String

Destroying Sessions and Unsetting Variables

Hour 17. Logging and Monitoring Server Activity