How To Create Login Page In Javascript With Database

Web Development Software

Creating a login page in JavaScript with a database can be an exciting and challenging task. In this article, I will guide you through the process of creating a login page with JavaScript and storing user data in a database. I will also share my personal insights and commentary along the way to make this journey even more interesting.

Setting Up the Database

The first step in creating a login page with a database is to set up the database itself. For this tutorial, we will be using a MySQL database. To get started, make sure you have a MySQL server installed on your machine. If not, you can easily download and install it from the MySQL website.

Once the MySQL server is installed, open up your preferred database management tool and create a new database. You can give it a name that is relevant to your project. In this example, let’s call it “usersdb”.

Next, create a table within the “usersdb” database to store user information. The table should have columns for username and password. You can also include additional columns for other user data such as email, name, or profile picture. Let’s create a table called “users” with columns “username” and “password”.

CREATE TABLE users (
username VARCHAR(255) NOT NULL,
password VARCHAR(255) NOT NULL
);

Creating the Login Form

Now that we have our database set up, let’s move on to creating the login form. In this example, we will be using HTML and JavaScript to create the login page.

Start by creating a new HTML file and add the necessary form elements for the login page. You can include fields for username and password, along with a submit button. Don’t forget to add the necessary styling to make it visually appealing.

Next, add a JavaScript function that will be triggered when the user submits the form. This function will handle the login logic by checking the entered username and password against the database.

function login() {
var username = document.getElementById("username").value;
var password = document.getElementById("password").value;

// Code to check username and password against the database
}

Connecting to the Database

In order to check the user’s credentials against the database, we need to establish a connection. For this, we will be using server-side scripting, specifically PHP.

Create a new PHP file and add code to establish a connection to the MySQL database. You will need to provide the appropriate hostname, username, password, and database name in the connection parameters.

<?php
$hostname = "localhost";
$username = "your_username";
$password = "your_password";
$database = "usersdb";

$conn = mysqli_connect($hostname, $username, $password, $database);

if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
?>

Validating User Credentials

Now that we have established a connection to the database, let’s move on to validating the user’s credentials. Modify the JavaScript login function to make an AJAX request to the server-side script for authentication.

function login() {
var username = document.getElementById("username").value;
var password = document.getElementById("password").value;

// Make an AJAX request to the server-side script for authentication
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
var response = JSON.parse(this.responseText);

if (response.success) {
// User authentication successful, redirect to home page
window.location.href = "home.html";
} else {
// User authentication failed, display error message
document.getElementById("error-message").textContent = response.message;
}
}
};

xhr.open("POST", "authenticate.php", true);
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send("username=" + username + "&password=" + password);
}

Handling Authentication on the Server

In the PHP file, add code to receive the username and password sent from the JavaScript function. Perform a database query to check if the entered credentials match any records in the “users” table.

<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$username = $_POST["username"];
$password = $_POST["password"];

$sql = "SELECT * FROM users WHERE username = '$username' AND password = '$password'";
$result = mysqli_query($conn, $sql);

if (mysqli_num_rows($result) > 0) {
$response = array("success" => true);
} else {
$response = array("success" => false, "message" => "Invalid username or password");
}

echo json_encode($response);
}
?>

Conclusion

Creating a login page in JavaScript with a database is a complex task that requires a combination of HTML, JavaScript, and server-side scripting. With the steps outlined in this article, you should have a good starting point for implementing a secure login system for your web application. Remember to always follow best practices for secure password storage and user authentication.

Feel free to explore additional features such as password hashing, user registration, or password recovery to enhance the functionality of your login page. Happy coding!