php实现注册登录
PHP 注册功能实现
创建数据库表(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) < 6) {
die('密码长度至少6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');
// 检查用户名/邮箱是否已存在
$stmt = $db->prepare("SELECT id FROM users WHERE username = ? OR email = ?");
$stmt->execute([$username, $email]);
if ($stmt->fetch()) {
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 (?, ?, ?)");
$result = $stmt->execute([$username, $email, $hashed_password]);
if ($result) {
header('Location: login.php');
exit;
} else {
die('注册失败');
}
}
?>
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'])) {
// 登录成功
$_SESSION['user_id'] = $user['id'];
$_SESSION['username'] = $user['username'];
header('Location: dashboard.php');
exit;
} else {
die('用户名或密码错误');
}
}
?>
安全增强措施
密码哈希使用 PHP 内置的 password_hash() 和 password_verify() 函数
防止 SQL 注入使用 PDO 预处理语句
登录后会话管理

// 检查是否登录
session_start();
if (!isset($_SESSION['user_id'])) {
header('Location: login.php');
exit;
}
// 登出功能
session_start();
session_destroy();
header('Location: login.php');
exit;
可选功能扩展
添加验证码防止暴力破解
实现记住我功能(使用安全cookie)
密码重置功能
电子邮件验证功能
用户资料管理功能






