PHP Session

What is PHP session

• Session allows the system to store information for later use.
• Session use for checking user authentications.
• Session and Cookie can use together for user authentications or store user information.

start a session

• You are always need to call the session_start() in order to use the session.

<?php
    session_start();
?>

to delete or destroy session

• This only delete the session variable
• Use to unset or delete each individual session.

<?php
    session_start();  
    if(isset($_SESSION['name'])){
       unset($_SESSION['name']); 
    }
?>

destroy all the session

• All everything will be destroy.
• Use this when you want destroy all the user session namely when user logout of the website.

<?php
     session_start(); 
     session_destroy();
?>

session example 1

• Set the session.
• call the session.
• assign the session value to the variable.
• Display Result: John

<?php
session_start();
$_SESSION['name'] = 'John';

$name = "";
if (isset($_SESSION['name'])) {
	$name = $_SESSION['name'];
}
?>

<h3><?php echo $name; ?></h3>

using session to count page

• Using session to count page for every page load.
• Display the total page count according to the page load.

<?php

session_start();
// assign session value
$_SESSION['id'] = 3232423;
$_SESSION['name'] = 'w3cyberlearning';
if(isset($_SESSION['count'])) {
     $_SESSION['count'] =  $_SESSION['count'] + 1;
}
else {
     $_SESSION['count'] =   1;
}
echo 'Name: '. $_SESSION['name'] . '<br/>';
echo 'Id: '. $_SESSION['id'] . '<br/>';
echo 'Total visit this page: '. $_SESSION['count'] . '<br/>';

?>

pass session value to other pages

• You can assess session information on other page.

first page (page1.php)

<?php

session_start();
$_SESSION['id'] = 3232423;
$_SESSION['name'] = 'w3cyberlearning';
if(isset($_SESSION['count'])) {
     $_SESSION['count'] =  $_SESSION['count'] + 1;
}
else {
     $_SESSION['count'] =   1;
}

echo 'Name: '. $_SESSION['name'] . '<br/>';
echo 'Id: '. $_SESSION['id'] . '<br/>';
echo 'Total visit this page: '. $_SESSION['count'] . '<br/>';

echo '<a href="page2.php">Second Page</a>';
?>

second page(page2.php)

• The second page, we assign the session values from the first page

to the variables.

<?php

session_start();

$id = 'undefine';
$name = 'undefine';
$count = 'undefine';

if(isset($_SESSION['id'])) {
      $id = $_SESSION['id'];
}
if(isset($_SESSION['name'])) {
      $name = $_SESSION['name'];
}
if(isset($_SESSION['count'])) {
      $count = $_SESSION['count'];
}

echo "This is the second page..<br/>" ;
echo 'Name: '. $_SESSION['name'] . '<br/>';
echo 'Id: '. $_SESSION['id'] . '<br/>';
echo 'Total visit this page: '. $_SESSION['count'] . '<br/>';

?>