告别PHP代码的“意大利面条”：如何使用topthink/think-container优雅解决依赖管理难题

// 假设这是你手动创建依赖的方式
$dbAdapter = new DatabaseAdapter();
$productRepo = new ProductRepository($dbAdapter);
$userRepo = new UserRepository($dbAdapter);
$orderService = new OrderService($productRepo, $userRepo);
$orderService->createOrder(...);

composer require topthink/think-container

use think\Container;

// 假设我们有这些类
class DatabaseAdapter { /* ... */ }
class ProductRepository {
    public function __construct(DatabaseAdapter $adapter) { /* ... */ }
}
class UserRepository {
    public function __construct(DatabaseAdapter $adapter) { /* ... */ }
}
class OrderService {
    public function __construct(ProductRepository $productRepo, UserRepository $userRepo) { /* ... */ }
}

$container = Container::getInstance();

// 1. 绑定类到容器
// 容器会自动解析 DatabaseAdapter 的依赖（如果它有的话，这里没有）
$container->bind(DatabaseAdapter::class);
$container->bind(ProductRepository::class);
$container->bind(UserRepository::class);
$container->bind(OrderService::class);

// 2. 从容器中获取对象
// 容器会自动实例化 OrderService 并注入 ProductRepository 和 UserRepository，
// 而这两个又会自动注入 DatabaseAdapter
$orderService = $container->make(OrderService::class);
$orderService->createOrder(...);

// 你也可以绑定接口到具体实现，实现更好的解耦
interface CacheInterface { public function get($key); }
class FileCache implements CacheInterface { public function get($key) { /* ... */ } }
$container->bind(CacheInterface::class, FileCache::class);
$cache = $container->make(CacheInterface::class); // 得到 FileCache 实例

// 获取容器实例
$container = \think\Container::getInstance();

// 绑定一个类、闭包、实例、接口实现到容器
$container->cache = '\app\common\Cache'; // 或者 CacheInterface::class

// 从容器中获取对象的唯一实例
$cacheInstance = $container->cache;

// 判断是否存在对象实例
isset($container->cache); // true

// 删除容器中的对象实例
unset($container->cache);

// think/App.php
namespace think;
class App
{
    public function name()
    {
        return 'My Application';
    }
}

// app/facade/App.php
namespace app\facade;

use think\Facade;

class App extends Facade
{
    protected static function getFacadeClass()
    {
        return \think\App::class; // 指向容器中实际的类名
    }
}

use app\facade\App;

echo App::name(); // 输出：My Application