php实现注册登录

PHP 注册功能实现

创建数据库表结构（以MySQL为例）

CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) NOT NULL UNIQUE,
    email VARCHAR(100) NOT NULL UNIQUE,
    password VARCHAR(255) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

注册表单HTML

<form action="register.php" method="post">
    <input type="text" name="username" placeholder="用户名" required>
    <input type="email" name="email" placeholder="邮箱" required>
    <input type="password" name="password" placeholder="密码" required>
    <input type="password" name="confirm_password" placeholder="确认密码" required>
    <button type="submit">注册</button>
</form>

register.php处理逻辑

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

    // 验证输入
    if (empty($username) || empty($email) || empty($password)) {
        die("所有字段必须填写");
    }

    if ($password !== $confirm_password) {
        die("两次密码输入不一致");
    }

    if (strlen($password) < 8) {
        die("密码长度至少8位");
    }

    // 密码哈希
    $hashed_password = password_hash($password, PASSWORD_DEFAULT);

    // 数据库连接
    $db = new PDO('mysql:host=localhost;dbname=your_db', 'username', 'password');

    // 检查用户是否存在
    $stmt = $db->prepare("SELECT id FROM users WHERE username = ? OR email = ?");
    $stmt->execute([$username, $email]);

    if ($stmt->rowCount() > 0) {
        die("用户名或邮箱已存在");
    }

    // 插入新用户
    $stmt = $db->prepare("INSERT INTO users (username, email, password) VALUES (?, ?, ?)");
    $stmt->execute([$username, $email, $hashed_password]);

    echo "注册成功";
}
?>

PHP 登录功能实现

登录表单HTML

<form action="login.php" method="post">
    <input type="text" name="username" placeholder="用户名或邮箱" required>
    <input type="password" name="password" placeholder="密码" required>
    <button type="submit">登录</button>
</form>

login.php处理逻辑

<?php
session_start();

if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $username = trim($_POST['username']);
    $password = $_POST['password'];

    if (empty($username) || empty($password)) {
        die("所有字段必须填写");
    }

    // 数据库连接
    $db = new PDO('mysql:host=localhost;dbname=your_db', 'username', 'password');

    // 查询用户
    $stmt = $db->prepare("SELECT * FROM users WHERE username = ? OR email = ?");
    $stmt->execute([$username, $username]);
    $user = $stmt->fetch();

    if (!$user || !password_verify($password, $user['password'])) {
        die("用户名或密码错误");
    }

    // 设置会话
    $_SESSION['user_id'] = $user['id'];
    $_SESSION['username'] = $user['username'];

    header("Location: dashboard.php");
    exit();
}
?>

安全增强措施

密码哈希使用PHP内置的password_hash和password_verify函数

$hashed_password = password_hash($password, PASSWORD_DEFAULT);
$is_valid = password_verify($input_password, $hashed_password);

防止SQL注入使用预处理语句

$stmt = $db->prepare("INSERT INTO users (username, email) VALUES (?, ?)");
$stmt->execute([$username, $email]);

会话管理

session_start();
$_SESSION['user_id'] = $user_id;
session_destroy(); // 退出登录时使用

密码重置功能

生成重置令牌

$token = bin2hex(random_bytes(32));
$expires = date('Y-m-d H:i:s', strtotime('+1 hour'));

发送重置邮件

$reset_link = "https://example.com/reset_password.php?token=$token";
mail($email, "密码重置", "请点击链接重置密码: $reset_link");

验证重置令牌

$stmt = $db->prepare("SELECT * FROM password_resets WHERE token = ? AND expires > NOW()");
$stmt->execute([$token]);