Chapter 23 - PowerPoint Presentation

Slide1

Chapter 23

Using Session Control in PHPSlide2

HTTP is a stateless protocol

No built in way of maintaining a state between two transactionsSlide3

PHP Sessions

Unique session ID – random number

Generated by PHP

Stored on client for the lifetime of the session

Stored as a cookieSlide4

Page1.php

<h1>Page 1</h1>

<?

php

session_start

();

$_SESSION['

sess_var

'] = "Hello World";

echo 'The contents of $_SESSION[\'

sess_var

\'] is '

.$_SESSION['

sess_var

'].'<

br

/>';

?>

<a

href

="page2.php">Next page</a>Slide5

Start_session

Checks to see whether there is a current session.

If not, it not it will create one.Slide6

Session variables

Superglobal

array $_SESSION

To create a session variable:

$_SESSION[‘id’] = 99;

When finished

u

nset($_SESSION[‘id’]);Slide7

Finish the session

session_destroy

( );Slide8

Page1.php

<h1>Page 1</h1>

<?

php

session_start

();

$_SESSION['

sess_var

'] = "Hello World";

echo 'The contents of $_SESSION[\'

sess_var

\'] is '

.$_SESSION['

sess_var

'].'<

br

/>';

?>

<a

href

="page2.php">Next page</a>Slide9

Page1.php

http://

cscdb.nku.edu/csc301/frank/Chapter23/page1.php

Slide10

Page2.php

<h1>Page 2</h1>

<?

php

session_start

();

echo 'The contents of $_SESSION[\'

sess_var

\'] is '

.$_SESSION['

sess_var

'].'<

br

/>';

unset($_SESSION['

sess_var

']);

?>Slide11

Page3.php

<h1>Page 3</h1>

<?

php

session_start

();

echo 'The contents of $_SESSION[\'

sess_var

\'] is '

.$_SESSION['

sess_var

'].'<

br

/>';

session_destroy

();

?>