php实现注册登陆
注册功能实现
使用PHP和MySQL实现用户注册功能,需要创建数据库表和处理表单提交。
创建用户表SQL语句:
CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
username VARCHAR(50) NOT NULL UNIQUE,
password VARCHAR(255) NOT NULL,
email VARCHAR(100) NOT NULL UNIQUE,
created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);
注册表单HTML(register.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>
注册处理逻辑(register.php):
<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$username = trim($_POST['username']);
$email = trim($_POST['email']);
$password = trim($_POST['password']);
$confirm_password = trim($_POST['confirm_password']);
if ($password !== $confirm_password) {
die("两次密码输入不一致");
}
$hashed_password = password_hash($password, PASSWORD_DEFAULT);
$dsn = 'mysql:host=localhost;dbname=your_database';
$db = new PDO($dsn, 'username', 'password');
$stmt = $db->prepare("INSERT INTO users (username, email, password) VALUES (?, ?, ?)");
$stmt->execute([$username, $email, $hashed_password]);
header("Location: login.php");
exit;
}
?>
登录功能实现
登录表单HTML(login.html):
<form action="login.php" method="post">
<input type="text" name="username" placeholder="用户名" required>
<input type="password" name="password" placeholder="密码" required>
<button type="submit">登录</button>
</form>
登录处理逻辑(login.php):
<?php
session_start();
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$username = trim($_POST['username']);
$password = trim($_POST['password']);
$dsn = 'mysql:host=localhost;dbname=your_database';
$db = new PDO($dsn, 'username', 'password');
$stmt = $db->prepare("SELECT * FROM users WHERE username = ?");
$stmt->execute([$username]);
$user = $stmt->fetch();
if ($user && password_verify($password, $user['password'])) {
$_SESSION['user_id'] = $user['id'];
$_SESSION['username'] = $user['username'];
header("Location: dashboard.php");
exit;
} else {
echo "用户名或密码错误";
}
}
?>
会话管理和登出
创建受保护页面(dashboard.php):
<?php
session_start();
if (!isset($_SESSION['user_id'])) {
header("Location: login.php");
exit;
}
echo "欢迎, " . htmlspecialchars($_SESSION['username']);
?>
<a href="logout.php">登出</a>
登出处理(logout.php):
<?php
session_start();
session_destroy();
header("Location: login.php");
exit;
?>
安全增强措施
密码哈希使用PHP的password_hash函数,验证使用password_verify函数。SQL查询使用预处理语句防止注入攻击。
添加CSRF防护:
// 在登录和注册页面生成token
$_SESSION['token'] = bin2hex(random_bytes(32));
// 在表单中添加隐藏字段
<input type="hidden" name="token" value="<?php echo $_SESSION['token']; ?>">
// 在处理脚本中验证token
if (!isset($_POST['token']) || $_POST['token'] !== $_SESSION['token']) {
die("无效的CSRF令牌");
}
实现输入验证:

// 验证用户名格式
if (!preg_match('/^[a-zA-Z0-9_]{3,20}$/', $username)) {
die("用户名只能包含字母、数字和下划线,长度3-20个字符");
}
// 验证邮箱格式
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
die("无效的邮箱地址");
}
// 验证密码强度
if (strlen($password) < 8) {
die("密码至少需要8个字符");
}






