Write a program to create a login form. On submitting the form, the user
should navigate to profile page.
Here’s a simple PHP program to create a login form that redirects to a profile page upon successful login. This example demonstrates basic authentication by verifying a hardcoded username and password for demonstration purposes.
Step 1: Create the Login Form (login.php)
<!DOCTYPE html>
<html lang=”en”>
<head>
<meta charset=”UTF-8″>
<meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
<title>Login</title>
</head>
<body>
<h2>Login Form</h2>
<form action=”authenticate.php” method=”post”>
<label for=”username”>Username:</label>
<input type=”text” id=”username” name=”username” required><br><br>
<label for=”password”>Password:</label>
<input type=”password” id=”password” name=”password” required><br><br>
<button type=”submit”>Login</button>
</form>
</body>
</html>
This form sends the entered username and password to authenticate.php for processing.
Step 2: Authenticate the User (authenticate.php)
In authenticate.php, verify the user’s credentials. If the login is successful, start a session and redirect to the profile page; otherwise, show an error message.
<?php
session_start();
// Hardcoded credentials for demonstration
$validUsername = “user”;
$validPassword = “password”;
// Retrieve form data
$username = $_POST[‘username’];
$password = $_POST[‘password’];
// Check credentials
if ($username === $validUsername && $password === $validPassword) {
// Successful login, set session variables
$_SESSION[‘username’] = $username;
// Redirect to profile page
header(“Location: profile.php”);
exit();
} else {
// Invalid credentials
echo “Invalid username or password. <a href=’login.php’>Try again</a>.”;
}
?>
Note: This example uses hardcoded credentials for simplicity. In a real application, retrieve and verify user credentials from a database.
Step 3: Create the Profile Page (profile.php)
In profile.php, check if the user is logged in by verifying the session variable. If not, redirect them back to the login page.
<?php
session_start();
// Check if the user is logged in
if (!isset($_SESSION[‘username’])) {
// Redirect to login page if not logged in
header(“Location: login.php”);
exit();
}
?>
<!DOCTYPE html>
<html lang=”en”>
<head>
<meta charset=”UTF-8″>
<meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
<title>Profile Page</title>
</head>
<body>
<h2>Welcome to Your Profile Page, <?php echo htmlspecialchars($_SESSION[‘username’]); ?>!</h2>
<p>This is a protected page that only logged-in users can access.</p>
<a href=”logout.php”>Logout</a>
</body>
</html>
Step 4: Logout Functionality (logout.php)
Add a logout.php page to destroy the session and log out the user.
<?php
session_start();
session_unset();
session_destroy();
// Redirect to login page after logout
header(“Location: login.php”);
exit();
?>
Summary of Files
- login.php: The login form.
- authenticate.php: Verifies credentials and starts a session.
- profile.php: Protected page, accessible only when logged in.
- logout.php: Logs out the user by destroying the session.