Superglobals as Concepts
Session Values
$_SESSION models server-side state associated with a visitor.
Session Values
session_values.php
<?php
$startCount = ;
$_SESSION["visits"] = $startCount;
$_SESSION["visits"] = $_SESSION["visits"] + 1;
$visits = $_SESSION["visits"];
$message = $visits > 1 ? "welcome back" : "first visit";
echo "visits=" . $visits . "\n";
echo "message=" . $message . "\n";
<?php
$startCount = ;
$_SESSION["visits"] = $startCount;
$_SESSION["visits"] = $_SESSION["visits"] + 1;
$visits = $_SESSION["visits"];
$message = $visits > 1 ? "welcome back" : "first visit";
echo "visits=" . $visits . "\n";
echo "message=" . $message . "\n";
<?php
$startCount = ;
$_SESSION["visits"] = $startCount;
$_SESSION["visits"] = $_SESSION["visits"] + 1;
$visits = $_SESSION["visits"];
$message = $visits > 1 ? "welcome back" : "first visit";
echo "visits=" . $visits . "\n";
echo "message=" . $message . "\n";
server-side memory
A session value can be read, updated, and used to choose a response label.