PHP Coding-PHP Interactive Coding

Example

$username = $_POST['username']; echo 'Welcome, ' . $username;

Scenario

In web forms where users input their data, PHP handles the input securely and displays or processes the data. This includes retrieving user data from forms, processing it, and outputting responses back to the user.

Example

$conn = new mysqli('localhost', 'user', 'password', 'database'); $result = $conn->query('SELECT * FROM users'); while ($row = $result->fetch_assoc()) { echo $row['username']; }

Scenario

PHP connects to a database to fetch, update, or delete data. This is crucial in applications like e-commerce sites or any system that requires data retrieval and manipulation, showcasing its utility in backend data management.

Example

session_start(); $_SESSION['user_id'] = 101; if (isset($_SESSION['user_id'])) { echo 'Session active'; }

Scenario

PHP manages user sessions, maintaining state over a stateless HTTP protocol. This is vital for ensuring that users are recognized across multiple pages of a website, such as in a shopping cart on an e-commerce site.

Example

mail('[email protected]', 'Welcome!', 'Thank you for registering with us!', 'From: [email protected]');

Scenario

PHP scripts can send emails to users directly from the server. This function is commonly used for registration confirmations, password resets, and promotional campaigns.