Setting up a login and logout system in PHP is straightforward, making it an ideal project for beginners. This guide will walk you through the steps to create a basic authentication system. We will create four files and a MySQL table to handle the user login and logout functionality.<\/p>\n\n\n\n
login.php<\/code><\/li>\n\n\n\nauthenticate.php<\/code><\/li>\n\n\n\nindex.php<\/code><\/li>\n\n\n\nlogout.php<\/code><\/li>\n<\/ul>\n\n\n\nMySQL Table Creation<\/h2>\n\n\n\n
First, we need to create a MySQL table to store user data. Use the following SQL script to create a users<\/code> table:<\/p>\n\n\n\nCREATE TABLE IF NOT EXISTS `users` (\n `id` int(11) NOT NULL AUTO_INCREMENT,\n `username` varchar(50) NOT NULL,\n `password` varchar(150) NOT NULL,\n `name` varchar(50) NOT NULL,\n `active` int(11) NOT NULL,\n PRIMARY KEY (`id`)\n) ENGINE=MyISAM;\n<\/code><\/pre>\n\n\n\nStep 1: Creating the Login Form (login.php<\/code>)<\/h2>\n\n\n\nWe start by creating a login form where users can input their username and password.<\/p>\n\n\n\n
<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n <meta charset=\"UTF-8\">\n <title>Login<\/title>\n<\/head>\n<body>\n <form action=\"authenticate.php\" method=\"post\">\n <table width=\"100%\" cellpadding=\"4\" cellspacing=\"0\" border=\"0\">\n <tr>\n <td>Username:<\/td>\n <td><input type=\"text\" name=\"username\" required><\/td>\n <\/tr>\n <tr>\n <td>Password:<\/td>\n <td><input type=\"password\" name=\"password\" required><\/td>\n <\/tr>\n <tr>\n <td><\/td>\n <td><input type=\"submit\" value=\"Login\"><\/td>\n <\/tr>\n <\/table>\n <\/form>\n<\/body>\n<\/html>\n<\/code><\/pre>\n\n\n\nExplanation<\/h3>\n\n\n\n\n- Form Action<\/strong>: The form’s action is set to
authenticate.php<\/code>, which means the data will be submitted to authenticate.php<\/code> for processing.<\/li>\n\n\n\n- Input Fields<\/strong>: Two fields are created for username and password. Both fields are required for submission.<\/li>\n\n\n\n
- Submit Button<\/strong>: A submit button is provided to send the form data.<\/li>\n<\/ul>\n\n\n\n
Step 2: Authenticating the User (authenticate.php<\/code>)<\/h2>\n\n\n\nThis file will handle the authentication logic.<\/p>\n\n\n\n
<?php\nsession_start();\n$conn = new mysqli('localhost', 'root', 'pass', 'test');\n\nif ($conn->connect_error) {\n die('Connection failed: ' . $conn->connect_error);\n}\n\nif ($_SERVER['REQUEST_METHOD'] == 'POST') {\n $username = trim($_POST['username']);\n $password = trim($_POST['password']);\n\n if ($username != '') {\n $stmt = $conn->prepare(\"SELECT * FROM users WHERE username = ? AND active = 1\");\n $stmt->bind_param('s', $username);\n $stmt->execute();\n $result = $stmt->get_result();\n $user = $result->fetch_assoc();\n\n if ($user && password_verify($password, $user['password'])) {\n $_SESSION['user_id'] = $user['id'];\n $_SESSION['username'] = $user['username'];\n header('Location: index.php');\n exit;\n } else {\n header('Location: login.php?err=1');\n exit;\n }\n }\n}\n?>\n<\/code><\/pre>\n\n\n\nExplanation<\/h3>\n\n\n\n\n- Session Start<\/strong>: We start a session to store user data upon successful login.<\/li>\n\n\n\n
- Database Connection<\/strong>: A connection to the MySQL database is established.<\/li>\n\n\n\n
- POST Check<\/strong>: We check if the form was submitted via POST.<\/li>\n\n\n\n
- User Validation<\/strong>: We retrieve the user record from the database and verify the password using
password_verify()<\/code>.<\/li>\n\n\n\n- Session Variables<\/strong>: If the user is authenticated, their ID and username are stored in session variables.<\/li>\n\n\n\n
- Redirection<\/strong>: Upon successful authentication, the user is redirected to
index.php<\/code>. If authentication fails, the user is redirected back to the login page with an error.<\/li>\n<\/ul>\n\n\n\nStep 3: Creating the Index Page (index.php<\/code>)<\/h2>\n\n\n\nThis page is accessible only to logged-in users.<\/p>\n\n\n\n
<?php\nsession_start();\nif (!isset($_SESSION['user_id'])) {\n header('Location: login.php');\n exit;\n}\n?>\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n <meta charset=\"UTF-8\">\n <title>Home<\/title>\n<\/head>\n<body>\n <p>You are now logged in<\/p>\n <a href=\"logout.php\">Logout<\/a>\n<\/body>\n<\/html>\n<\/code><\/pre>\n\n\n\nExplanation<\/h3>\n\n\n\n\n- Session Check<\/strong>: We check if the user ID is set in the session. If not, the user is redirected to the login page.<\/li>\n\n\n\n
- Logged In Message<\/strong>: A simple message is displayed indicating that the user is logged in.<\/li>\n\n\n\n
- Logout Link<\/strong>: A link is provided to log out.<\/li>\n<\/ul>\n\n\n\n
Step 4: Creating the Logout Script (logout.php<\/code>)<\/h2>\n\n\n\nThis script handles the user logout process.<\/p>\n\n\n\n
<?php\nsession_start();\nsession_unset();\nsession_destroy();\nheader('Location: login.php');\nexit;\n?>\n<\/code><\/pre>\n\n\n\nExplanation<\/h3>\n\n\n\n\n- Session Handling<\/strong>: The session is started, and then all session variables are unset, and the session is destroyed.<\/li>\n\n\n\n
- Redirection<\/strong>: The user is redirected to the login page after logging out.<\/li>\n<\/ul>\n\n\n\n
Conclusion<\/h3>\n\n\n\n
With these steps, you have created a basic login\/logout system in PHP. This system includes:<\/p>\n\n\n\n
\n- A login form for user input.<\/li>\n\n\n\n
- An authentication script to verify user credentials.<\/li>\n\n\n\n
- A protected page accessible only to authenticated users.<\/li>\n\n\n\n
- A logout script to end the user session.<\/li>\n<\/ul>\n\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
Learn how to create a simple and secure login\/logout system in PHP with this step-by-step guide for beginners. This tutorial covers creating a user login form, authenticating users, managing sessions, and handling logout functionality using PHP and MySQL.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[10,7,8,6,9],"class_list":["post-4","post","type-post","status-publish","format-standard","hentry","category-php","tag-global-variables","tag-login","tag-logout","tag-php-2","tag-session-data"],"_links":{"self":[{"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/posts\/4","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/comments?post=4"}],"version-history":[{"count":3,"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/posts\/4\/revisions"}],"predecessor-version":[{"id":397,"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/posts\/4\/revisions\/397"}],"wp:attachment":[{"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/media?parent=4"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/categories?post=4"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scriptut.com\/wp-json\/wp\/v2\/tags?post=4"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}