不使用框架的PHP开发模式

<?php

//模型
class Model {
    protected $db;

    public function __construct() {
        $this->db = new PDO("mysql:host=localhost;dbname=mydatabase", "username", "password");
    }
}

//视图
class View {
    protected $data;

    public function render($template) {
        include($template);
    }

    public function assign($key, $value) {
        $this->data[$key] = $value;
    }
}

//控制器
class Controller {
    protected $model;
    protected $view;

    public function __construct($model, $view) {
        $this->model = $model;
        $this->view = $view;
    }

    public function index() {
        $result = $this->model->get_data();
        $this->view->assign('data', $result);
        $this->view->render('template.php');
    }
}

//实例化控制器
$model = new Model();
$view = new View();
$controller = new Controller($model, $view);

//处理请求
$controller->index();

<?php

//路由规则
$routes = array(
    '/' => 'home.php',
    '/about' => 'about.php'
);

//获取请求路径
$url = parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH);

//查找路由规则
$file = $routes[$url];

//加载对应的控制器
if ($file) {
    include($file);
}

<?php

//数据访问类
class DataAccess {
    private $connection; 

    public function __construct($host, $username, $password, $database) {
        $this->connection = new PDO("mysql:host=$host;dbname=$database", $username, $password);
    }

    public function query($query) {
        return $this->connection->query($query);
    }

    public function prepare($query) {
        return $this->connection->prepare($query);
    }

    public function lastInsertId() {
        return $this->connection->lastInsertId();
    }

    public function beginTransaction() {
        return $this->connection->beginTransaction();
    }

    public function commit() {
        return $this->connection->commit();
    }

    public function rollBack() {
        return $this->connection->rollBack();
    }
}

//实例化数据访问类
$database = new DataAccess('localhost', 'username', 'password', 'mydatabase');

//使用数据访问类执行查询操作
$result = $database->query('SELECT * FROM users');

//使用数据访问类执行预处理操作
$stmt = $database->prepare('INSERT INTO users (username, password) VALUES (:username, :password)');
$stmt->execute(array('username' => 'john', 'password' => 'password123'));