Ninject Lazy Load问题

参考：

http://stackoverflow.com/questions/2538132/lazy-loading-with-ninject 

方案一：

public class Module : NinjectModule
{
    public override void Load()
    {
        Bind(typeof(Lazy<>)).ToMethod(ctx => 
                GetType()
                    .GetMethod("GetLazyProvider", BindingFlags.Instance | BindingFlags.NonPublic)
                    .MakeGenericMethod(ctx.GenericArguments[0])
                    .Invoke(this, new object[] { ctx.Kernel }));
    }

    protected Lazy<T> GetLazyProvider<T>(IKernel kernel)
    {
        return new Lazy<T>(() => kernel.Get<T>());
    }
}

 

方案二：

Ninject Lazy Load

namespace LayzyLoadTest
{
    [TestClass]
    public class UnitTest1
    {


        private IKernel InitKernel()
        {
            Ninject.IKernel kernel = new Ninject.StandardKernel(new LazyBinding());

            //kernel.Load<LazyBinding>();

            kernel.Bind<IPerson>().To<Father>();
            kernel.Bind<IVehicle>().To<Car>();

            kernel.Bind<IPlace>().To<Road>().Named("comm");
            kernel.Bind<IPlace>().To<LazyRoad>().Named("lazy");

            return kernel;
        }

        [TestMethod]
        public void TestMethod1()
        {



            var comm = InitKernel().Get<IPlace>("comm");

            comm.CurSpeed();
            comm.ShowSpeed();

            //Console.WriteLine("------------------------------------------------");

            //var lazy = kernel.Get<IPlace>("lazy");

            ////lazy.CurSpeed();
            ////lazy.ShowSpeed();



        }

        [TestMethod]
        public void Lazy()
        {


            var lazy = InitKernel().Get<IPlace>("lazy");

            lazy.CurSpeed();

            Console.WriteLine("----over curspeed--------------------");

            lazy.ShowSpeed();
        }
    }
}

 

namespace LayzyLoadTest.LayzyClasses
{
    #region Persons

    interface IPerson
    {
        int RunSpeed();
    }



    class Child : IPerson
    {
        public Child()
        {
            Console.WriteLine("Ctor Child");
        }
        public int RunSpeed()
        {
            Console.WriteLine("Child's Speed");

            return 100;
        }
    }

    class Father : IPerson
    {
        public Father()
        {
            Console.WriteLine("Ctor Father");
        }
        public int RunSpeed()
        {
            Console.WriteLine("Father's Speed");
            return 1000;
        }
    }

    interface IVehicle
    {
        int Improve();
    }

    class Car : IVehicle
    {
        public Car()
        {
            Console.WriteLine("Car's Ctor");
        }
        public int Improve()
        {
            Console.WriteLine("Car Improve");
            return 1000;
        }
    }

    class Bicycle : IVehicle
    {
        public Bicycle()
        {
            Console.WriteLine("Bicycle's Ctor");
        }
        public int Improve()
        {
            Console.WriteLine("Bicycle Improve");
            return 100;
        }
    }

    #endregion

    #region Place

    interface IPlace
    {
        int CurSpeed();
        int ShowSpeed();
    }

    class Road : IPlace
    {
        private readonly IPerson _person;
        private readonly IVehicle _vehicle;

        public Road(IPerson person, IVehicle vehicle)
        {
            Console.WriteLine(" Road's Ctor ");
            _person = person;
            _vehicle = vehicle;
        }

        public int CurSpeed()
        {
            Console.WriteLine("Road CurSpeed");
            return _person.RunSpeed();
        }

        public int ShowSpeed()
        {
            Console.WriteLine("Road ShowSpeed");
            return _person.RunSpeed() * _vehicle.Improve();
        }
    }

    class LazyRoad : IPlace
    {
        private readonly Lazy<IPerson> _person;
        private readonly Lazy<IVehicle> _vehicle;

        public LazyRoad(Lazy<IPerson> person, Lazy<IVehicle> vehicle)
        {
            Console.WriteLine(" LazyRoad's Ctor ");
            _person = person;
            _vehicle = vehicle;
        }

        public int CurSpeed()
        {
            Console.WriteLine("LazyRoad CurSpeed");
            return _person.Value.RunSpeed();
        }

        public int ShowSpeed()
        {
            Console.WriteLine("LazyRoad ShowSpeed");
            return _person.Value.RunSpeed() * _vehicle.Value.Improve();
        }
    }

    #endregion


}

namespace LayzyLoadTest
{
    public class LazyBinding : NinjectModule
    {
        public override void Load()
        {
            this.Bind(typeof(Lazy<>))
                .ToMethod(
                    context =>
                    ((ILazyLoader)Activator.CreateInstance(typeof(LazyLoader<>).MakeGenericType(context.GenericArguments),
                                                           new object[] { context.Kernel })).Loader);
        }

        public interface ILazyLoader
        {
            object Loader { get; }
        }

        public class LazyLoader<T> : ILazyLoader
        {
            private readonly IKernel _kernel;
            private static readonly Func<IKernel, Lazy<T>> _lazyLoader = k => new Lazy<T>(() => k.Get<T>());

            public LazyLoader(IKernel kernel)
            {
                if (kernel == null)
                    throw new ArgumentNullException("kernel");

                this._kernel = kernel;
            }

            public object Loader { get { return _lazyLoader(this._kernel); } }
        }
    }
}