Why Is My PHP Login Form Failing to Connect to MySQL?

Why Can't My Login Form Connect to the MySQL Database?

Your login form is unable to connect to the MySQL database due to several reasons. The following responses provide comprehensive solutions to address the potential issues:

Secure Password Handling:

It is crucial to protect user passwords by using password hashing instead of storing them in plaintext. Utilize functions like password_hash() to encrypt passwords unidirectionally, ensuring their security.

SQL Injection Prevention:

Avoid using user-supplied data directly in your SQL queries. Employ prepared statements and bind parameters to prevent malicious SQL injection attacks, which can compromise your database.

mysqli Functionality with Code Examples:

register.php

// DB Credentials
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "user_accounts2";

// Secure Connection
mysqli_report(MYSQLI_REPORT_ALL);
error_reporting(E_ALL);
ini_set("display_errors", 1);

// Database Connection
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// User Registration
if (isset($_POST['register'])) {
    $email = mysqli_real_escape_string($conn, $_POST['email']);
    $password = mysqli_real_escape_string($conn, $_POST['password']);

    // Password Hashing
    $hashed_password = password_hash($password, PASSWORD_DEFAULT);

    // Prepared Statement and Parameter Binding
    $stmt = $conn->prepare("INSERT INTO user_accounts2 (email, password) VALUES (?, ?)");
    $stmt->bind_param("ss", $email, $hashed_password);

    // Query Execution
    $stmt->execute();
}

// Close Connection
$stmt->close();
$conn->close();

login.php

// DB Credentials and Secure Connection Same as register.php

// User Login
if (isset($_POST['login'])) {
    $email = mysqli_real_escape_string($conn, $_POST['email']);
    $password = mysqli_real_escape_string($conn, $_POST['password']);

    // Prepared Statement and Parameter Binding
    $stmt = $conn->prepare("SELECT * FROM user_accounts2 WHERE email = ?");
    $stmt->bind_param("s", $email);

    // Query Execution
    $stmt->execute();
    $result = $stmt->get_result();

    if ($row = $result->fetch_assoc()) {
        // Password Verification
        if (password_verify($password, $row['password'])) {
            echo "Logged in successfully!";
        } else {
            echo "Invalid credentials";
        }
    } else {
        echo "User not found";
    }

    // Close Statement and Connection
    $stmt->close();
    $conn->close();
}

pdo Functionality with Code Examples:

Refer to this resource for a detailed example of user authentication using PDO: [Answer: PDO User Authentication](https://stackoverflow.com/questions/5926241/php-pdo-user-authentication/5927236#5927236)

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