PHP开发实践：使用PHP和MySQL实现邮箱验证功能

<form action="register.php" method="POST">
  <label for="email">邮箱地址：</label>
  <input type="email" id="email" name="email" required>
  <br>
  <label for="password">密码：</label>
  <input type="password" id="password" name="password" required>
  <br>
  <input type="submit" value="注册">
</form>

<?php
// 连接到MySQL数据库
$mysqli = new mysqli("localhost", "username", "password", "database_name");
if ($mysqli->connect_error) {
    die("连接数据库失败: " . $mysqli->connect_error);
}

// 获取用户提交的表单数据
$email = $_POST['email'];
$password = $_POST['password'];

// 检查邮箱地址是否有效
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
    die("无效的邮箱地址");
}

// 检查邮箱地址是否已被注册
$sql = "SELECT * FROM users WHERE email = '$email'";
$result = $mysqli->query($sql);
if ($result->num_rows > 0) {
    die("该邮箱地址已被注册");
}

// 生成验证码
$verificationCode = uniqid();

// 将新用户的数据插入数据库
$sql = "INSERT INTO users (email, password, verification_code) VALUES ('$email', '$password', '$verificationCode')";
if ($mysqli->query($sql) === TRUE) {
    echo "注册成功";
} else {
    echo "注册失败: " . $mysqli->error;
}

// 发送验证邮件（需要使用你自己的SMTP服务器配置）
$to = $email;
$subject = "账户激活";
$message = "请点击以下链接激活您的账户：" . "http://example.com/activate.php?code=".urlencode($verificationCode);
$headers = "From: noreply@example.com
" . "Reply-To: noreply@example.com
";
mail($to, $subject, $message, $headers);

$mysqli->close();
?>

<?php
// 连接到MySQL数据库
$mysqli = new mysqli("localhost", "username", "password", "database_name");
if ($mysqli->connect_error) {
    die("连接数据库失败: " . $mysqli->connect_error);
}

// 获取用户提交的验证码
$verificationCode = $_GET['code'];

// 更新数据库中对应用户的激活状态
$sql = "UPDATE users SET is_activated = 1 WHERE verification_code = '$verificationCode'";
if ($mysqli->query($sql) === TRUE) {
    echo "账户激活成功";
} else {
    echo "账户激活失败: " . $mysqli->error;
}

$mysqli->close();
?>