Ninject 单例未作为单例注入依赖 Class

Question

我正在创建一个 PersonalityConfiguration class，我希望它成为一个单例，并且在大多数情况下，单例绑定工作正常。除非此 "Singleton" 通过 Class 的构造函数中的 IPersonalityProvider 接口绑定。注入绑定时，它不是单例，不是 PersonalityConfiguration 的同一个实例，而是每次都是一个新实例。我如何通过 IPersonalityProvider 接口将同一个单例绑定到依赖的 classes？

我有以下界面和 Class 定义

接口 IPersonalityProvider

interface IPersonalityProvider
{
    void BeHappy();
}

Class个性配置

class PersonalityConfiguration : IPersonalityProvider
{
    private int m_personalityScale = 0;
    public PersonalityConfiguration()
    {
        m_personalityScale = 0;
    }

    public void BeHappy()
    {
        throw new NotImplementedException();
    }
}

Class 人

class Person
{
    public Person(IPersonalityProvider personality)
    {
        Personality = personality;
    }

    public IPersonalityProvider Personality { get; set; }
}

我的Ninject模块如下

class ProgramNinjectModule : NinjectModule
{
    public override void Load()
    {
        Bind<PersonalityConfiguration>().ToSelf().InSingletonScope();
        Bind<IPersonalityProvider>().To<PersonalityConfiguration>();
    }
}

这是我的主要内容

   static void Main(string[] args)
    {
        using (var nKernel = new StandardKernel(new ProgramNinjectModule()))
        {

            //Singleton works here
            PersonalityConfiguration crazy1 = nKernel.Get<PersonalityConfiguration>();  
            PersonalityConfiguration crazy2 = nKernel.Get<PersonalityConfiguration>();  
            Assert.AreEqual(crazy1, crazy2); //True as Expected

            //Expecting PersonalityConfig Singleton to bind to Person1 and 2, does not
            Person person1 = nKernel.Get<Person>();  
            Person person2 = nKernel.Get<Person>();
            Assert.AreEqual(person1.Personality, person2.Personality);  //False, Bombs

            //Obviously this works
            Person person3 = new Person(crazy1);
            Person person4 = new Person(crazy1);
            Assert.AreEqual(person3.Personality, person4.Personality);  //True as Expected
        }

    }

Answer 1

看来我使用了以下绑定并且有效

class ProgramNinjectModule : NinjectModule
{
    public override void Load()
    {
        Bind<PersonalityConfiguration>().ToSelf().InSingletonScope();
        Bind<IPersonalityProvider>().ToMethod(n => n.Kernel.Get<PersonalityConfiguration>()).WhenInjectedInto<Person>();
    }
}

Answer 2

实现您想要的目标的简洁方法是通过一个绑定：

Bind<IPersonalityProvider, PersonalityConfiguration>()
    .To<PersonalityConfiguration>()
    .InSingletonScope();

这意味着每当 ninject 被请求 return 一个 IPersonalityProvider 或一个 PersonalityConfiguration 它会 return PersonalityConfiguration.

的相同（单例）实例

我已经使用以下代码验证它可以正常工作：

using System;
using FluentAssertions;
using Ninject;
using Ninject.Modules;
using Xunit;

namespace NinjectTest.SingletonBoundToMultipleTypes
{
    interface IPersonalityProvider
    {
        void BeHappy();
    }

    class PersonalityConfiguration : IPersonalityProvider
    {
        private int m_personalityScale = 0;
        public PersonalityConfiguration()
        {
            m_personalityScale = 0;
        }

        public void BeHappy()
        {
            throw new NotImplementedException();
        }
    }

    class Person
    {
        public Person(IPersonalityProvider personality)
        {
            Personality = personality;
        }

        public IPersonalityProvider Personality { get; set; }
    }

    class ProgramNinjectModule : NinjectModule
    {
        public override void Load()
        {
            Bind<IPersonalityProvider, PersonalityConfiguration>()
                .To<PersonalityConfiguration>()
                .InSingletonScope();
        }
    }

    public class Test
    {
        [Fact]
        public void PerformTest()
        {
            using (var nKernel = new StandardKernel(new ProgramNinjectModule()))
            {
                //Singleton works here
                PersonalityConfiguration crazy1 = nKernel.Get<PersonalityConfiguration>();
                PersonalityConfiguration crazy2 = nKernel.Get<PersonalityConfiguration>();
                ReferenceEquals(crazy1, crazy2).Should().BeTrue();

                //Expecting PersonalityConfig Singleton to bind to Person1 and 2, does not
                Person person1 = nKernel.Get<Person>();
                Person person2 = nKernel.Get<Person>();
                ReferenceEquals(person1.Personality, person2.Personality)
                    .Should().BeTrue();

                //Obviously this works
                Person person3 = new Person(crazy1);
                Person person4 = new Person(crazy1);
                ReferenceEquals(person3.Personality, person4.Personality)
                    .Should().BeTrue();
            }
        }
    }
}

Ninject 单例未作为单例注入依赖 Class

Ninject Singleton not being injected as Singleton into Dependent Class

c#

binding

dependency-injection

singleton

ninject