The following article explains How to Create a Login Application in PHP.
In order to create a login application in PHP, you need to follow the steps below.
- Create a database to store user credentials (username and password) and connect it to your PHP script.
- Then, create a login form in HTML with input fields for username and password.
- After that, write a PHP script to validate the user’s input against the credentials stored in the database.
- If the validation is successful, start a session and redirect the user to their profile page.
- Otherwise, if the validation fails, display an error message and ask the user to try again.
The following code shows an example of how you can create a login application in PHP.
HTML code for login form
<form action="login.php" method="post">
<label for="username">Username:</label>
<input type="text" id="username" name="username"><br><br>
<label for="password">Password:</label>
<input type="password" id="password" name="password"><br><br>
<input type="submit" value="Login">
</form>
PHP code for login script
<?php
session_start();
if(isset($_POST['username']) && isset($_POST['password'])) {
//connect to database
$conn = mysqli_connect("localhost", "username", "password", "database_name");
//sanitize user input
$username = mysqli_real_escape_string($conn, $_POST['username']);
$password = mysqli_real_escape_string($conn, $_POST['password']);
//query to check user credentials
$query = "SELECT * FROM users WHERE username='$username' AND password='$password'";
$result = mysqli_query($conn, $query);
if(mysqli_num_rows($result) > 0) {
//user authentication successful
$_SESSION['username'] = $username;
header("Location: profile.php");
}
else {
//user authentication failed
echo "Invalid username or password. Please try again.";
}
mysqli_close($conn);
}
?>
In the code above, replace “username”, “password”, and “database_name” with your actual credentials and database name.
The code checks if the username and password fields are filled in the HTML form. Then it connects to the database, sanitizes the user input to prevent SQL injection, and queries the database to check if the user credentials match. If the validation is successful, it starts a session with the username and redirects the user to their profile page. If the validation fails, it displays an error message asking the user to try again.
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