Ninject:将多个类型绑定到同一个单例实例 [英] Ninject: Bind multiple types to the same singleton instance

问题描述

interface IService<T> {}

class ConcreteServiceA<T> : IService<T> {}

我需要:

IService<string> stringServices = kernel.Get<IService<string>>();
ConcreteServiceA<string> concreteStringServiceA = kernel.Get<ConcreteServiceA<string>>();

Assert.IsSameReference(stringService, concreteStringServiceA);

到目前为止，我尝试创建绑定:

Up to now, I've tried to create bindings:

this.Bind(typeof(IService<>))
    .To(typeof(ConcreteServiceA<>))
    .InSingletonScope();

this.Bind(typeof(ConcreteServiceA<>)).ToSelf().InSingletonScope();

不过，使用此绑定，当我请求IService<string>和ConcreteServiceA<string>时，我得到了两个不同的实例:

Nevertheless, using this binding I'm getting two different instances when i request for a IService<string> and for a ConcreteServiceA<string>:

kernel.Get<IService<string>>() instance is different of kernel.Get<ConcreteService<string>>()

有什么想法吗?

推荐答案

您可以指定多个类型以同时绑定，例如:

You can specify multiple types to bind at the same time, e.g.:

this.Bind(typeof(IService<>), typeof(ConcreteServiceA<>))
    .To(typeof(ConcreteServiceA<>))
    .InSingletonScope();

我进行了一些测试以确认这一点:

Some tests I made to confirm this:

kernel.Bind(typeof(IList<>)).To(typeof(List<>)).InSingletonScope();
kernel.Bind(typeof(List<>)).ToSelf().InSingletonScope();

var list1 = kernel.Get<IList<string>>();
var list2 = kernel.Get<List<string>>();

Assert.IsTrue(list1.Equals(list2)); // fails as per your question


kernel.Bind(typeof(IList<>), typeof(List<>)).To(typeof(List<>)).InSingletonScope();

var list1 = kernel.Get<IList<string>>();
var list2 = kernel.Get<List<string>>();

Assert.IsTrue(list1.Equals(list2)); // passes

这篇关于Ninject:将多个类型绑定到同一个单例实例的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！