How Can I Use PHP Sessions to Manage User Login State?

Implementing Sessions in a PHP Login Script to Maintain User State

Your inquiry showcases your interest in leveraging sessions in a PHP login script. Sessions are crucial for preserving user state across multiple page requests, allowing you to identify and track logged-in users.

Initiating a Session

To initiate a session, incorporate the following code at the commencement of your script:

session_start();

This initializes a session and enables you to store and retrieve session variables.

Storing and Retrieving User ID in the Session

To identify logged-in users, store their user ID in the session:

$_SESSION['user'] = $user_id;

This assigns the user ID to the session variable 'user'.

Checking for Logged-in Users

To verify if a user is currently logged in, use this conditional statement:

if (isset($_SESSION['user'])) {
   // logged in
} else {
   // not logged in
}

The isset() function ensures the 'user' session variable exists before proceeding.

Retrieving the Logged-in User's ID

You can retrieve the current logged-in user's ID using:

$_SESSION['user']

Returning to your webpage, you can now implement a conditional display based on user login status:

<?php session_start();


if (isset($_SESSION['user'])) {
?>
   <!-- Display HTML and code for logged-in users -->
<?php } else {
?>
   <!-- Display HTML and code for non-logged-in users -->
<?php }
?>

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