phpweb授权帐号

<?php
// 示例代码：用户登录验证
$username = $_POST['username'];
$password = $_POST['password'];

// 连接数据库
$conn = new mysqli("localhost", "username", "password", "database");

if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 查询用户信息
$sql = "SELECT * FROM users WHERE username = '$username' AND password = '$password'";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    echo "登录成功";
} else {
    echo "用户名或密码错误";
}

$conn->close();
?>

<?php
// 示例代码：权限检查
$user_id = $_SESSION['user_id'];

// 查询用户角色和权限
$sql = "SELECT role, permissions FROM users WHERE id = $user_id";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    $row = $result->fetch_assoc();
    $role = $row['role'];
    $permissions = json_decode($row['permissions'], true);

    // 检查权限
    if (in_array('admin', $permissions)) {
        echo "权限足够";
    } else {
        echo "权限不足";
    }
}
?>