实现php登录功能实现
PHP登录功能实现
数据库准备
创建一个用户表存储用户名和密码(密码需加密存储):
CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
username VARCHAR(50) NOT NULL UNIQUE,
password VARCHAR(255) NOT NULL,
created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);
注册功能实现
使用PHP处理用户注册请求,密码使用password_hash加密:
<?php
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$username = $_POST['username'];
$password = password_hash($_POST['password'], PASSWORD_DEFAULT);
$stmt = $pdo->prepare("INSERT INTO users (username, password) VALUES (?, ?)");
$stmt->execute([$username, $password]);
}
?>
登录表单设计
创建HTML登录表单:

<form action="login.php" method="post">
<input type="text" name="username" placeholder="用户名" required>
<input type="password" name="password" placeholder="密码" required>
<button type="submit">登录</button>
</form>
登录验证逻辑
验证用户凭据并启动会话:
<?php
session_start();
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$username = $_POST['username'];
$password = $_POST['password'];
$stmt = $pdo->prepare("SELECT * FROM users WHERE username = ?");
$stmt->execute([$username]);
$user = $stmt->fetch();
if ($user && password_verify($password, $user['password'])) {
$_SESSION['user_id'] = $user['id'];
header('Location: dashboard.php');
} else {
echo "无效的用户名或密码";
}
}
?>
会话管理
检查用户是否已登录:

<?php
session_start();
if (!isset($_SESSION['user_id'])) {
header('Location: login.php');
exit;
}
?>
安全增强措施
- 使用预处理语句防止SQL注入
- 启用HTTPS传输数据
- 设置CSRF令牌
- 实现登录尝试限制
- 使用现代加密算法(如Argon2)
密码重置功能
实现密码重置流程:
// 生成重置令牌
$token = bin2hex(random_bytes(32));
$stmt = $pdo->prepare("UPDATE users SET reset_token = ?, token_expires = DATE_ADD(NOW(), INTERVAL 1 HOUR) WHERE email = ?");
$stmt->execute([$token, $email]);
// 发送包含重置链接的邮件
$resetLink = "https://example.com/reset-password.php?token=$token";
mail($email, "密码重置", "请访问此链接重置密码: $resetLink");
记住登录状态
使用持久化cookie实现记住登录:
if (isset($_POST['remember'])) {
$selector = bin2hex(random_bytes(8));
$validator = random_bytes(32);
$hashedValidator = password_hash($validator, PASSWORD_DEFAULT);
$expires = date('Y-m-d H:i:s', time() + 86400 * 30);
$stmt = $pdo->prepare("INSERT INTO auth_tokens (user_id, selector, hashed_validator, expires) VALUES (?, ?, ?, ?)");
$stmt->execute([$user['id'], $selector, $hashedValidator, $expires]);
setcookie('remember', $selector.':'.bin2hex($validator), time() + 86400 * 30, '/', '', true, true);
}






