C# 如何在构造函数中正确注入服务？

我有一个简单的界面和一个简单的控制台应用程序

public interface ICustomerService
{
    string Operation();
}

以及一个实现上述接口的服务

现在我声明了一个unity容器，以便使用依赖注入模式和一个名为

CustomerController

的类

var container = new UnityContainer();
container.RegisterType<ICustomerService, CustomerService>();
CustomerController c = new CustomerController();
c.Operation();

我知道对于

webapi

和

MVC

应用程序，它使用了

dependencysolver

public class CustomerController
{
    private readonly ICustomerService _customerService;

    public CustomerController()
    {

    }
    [InjectionConstructor]
    public CustomerController(ICustomerService customerService)
    {
        _customerService = customerService;
    }

    public void Operation()
    {
        Console.WriteLine(_customerService.Operation());
    }
}

DependencyResolver.SetResolver(new UnityDependencyResolver(container)); 

---

但是如何在一个简单的控制台应用程序中正确地注入

服务

也向容器注册

CustomerController

public static void Main(string[] args) {

    var container = new UnityContainer()
        .RegisterType<ICustomerService, CustomerService>()
        .RegisterType<CustomerController>();

    CustomerController c = container.Resolve<CustomerController>();
    c.Operation();

    //...
}

---

同时向容器注册

CustomerController

。在解析控制器时，容器将注入依赖项。使用Core 2，所有内容都是控制台应用程序，包括Web API和Web应用程序。服务是从构造函数的参数自动注入的。您不需要空的默认构造函数。

public static void Main(string[] args) {

    var container = new UnityContainer()
        .RegisterType<ICustomerService, CustomerService>()
        .RegisterType<CustomerController>();

    CustomerController c = container.Resolve<CustomerController>();
    c.Operation();

    //...
}

public class CustomerController {
    private readonly ICustomerService _customerService;

    [InjectionConstructor]
    public CustomerController(ICustomerService customerService) {
        _customerService = customerService;
    }

    public void Operation() {
        Console.WriteLine(_customerService.Operation());
    }
}