PHP中封装性的代码复用和组件化

class Database {
    private $conn;
    
    public function __construct($host, $username, $passWord, $database) {
        $this->conn = new Mysqli($host, $username, $password, $database);
        
        if ($this->conn->connect_error) {
            die("Connection failed: " . $this->conn->connect_error);
        }
    }
    
    public function query($sql) {
        $result = $this->conn->query($sql);
        
        if ($result === false) {
            die("Query failed: " . $this->conn->error);
        }
        
        return $result;
    }
    
    public function insert($table, $data) {
        $fields = implode(', ', array_keys($data));
        $values = "'" . implode("', '", array_values($data)) . "'";
        
        $sql = "INSERT INTO $table ($fields) VALUES ($values)";
        
        return $this->query($sql);
    }
    
    // 其他的操作方法，如更新和删除
}

$db = new Database('localhost', 'root', 'password', 'mydb');
$data = array('name' => 'John Doe', 'email' => 'john@example.com');
$db->insert('users', $data);

class Carousel {
    private $images;
    
    public function __construct($images) {
        $this->images = $images;
    }
    
    public function render() {
        echo '<div class="carousel">';
        
        foreach ($this->images as $image) {
            echo '<img src="' . $image . '" alt="Slide">';
        }
        
        echo '</div>';
    }
}

$images = array('image1.jpg', 'image2.jpg', 'image3.jpg');
$carousel = new Carousel($images);
$carousel->render();