NInject 3泄漏（有一个示例项目），是否可以强制移除对象？

Question

I created a sample project to model what I faced in my real project. The problem is that when I query some external data in a cycle (in the real life my project queries windows to find match(es), and stops querying on success or on timeout expiration). It seems to me that NInject does not dispose created objects and consider the cycle as one long call. How to work around this situation? Maybe, cut out the code that fills list and put it into another class? Or simply, could you make my sample project better?

The link on Github or its code below:

public interface IMyObj : IDisposable
{
    string Name { get; set; }
}

public class MyObj : IMyObj
{
    public virtual string Name { get; set; }

    public virtual void Dispose()
    {
        Name = string.Empty;
        GC.SuppressFinalize(this);
    }
}

public class NjModule : NinjectModule
{
    public override void Load()
    {
        Bind<IMyObj>()
            .To<MyObj>()
            .InCallScope();

        Bind<Requester>()
            .ToSelf()
            .InSingletonScope();
    }
}

public class Requester
{
    public List<IMyObj> RequestObjects()
    {
        List<IMyObj> list = new List<IMyObj>();

        for(int i = 0; i < 10; i++) {
            var myObj = Program.Kernel.Get<IMyObj>();
            myObj.Name = "abcdefghijklmnopqrstuvwxyz";
            list.Add(myObj);
        }

        return list;
    }
}

class Program
{
    public static IKernel Kernel;

    public static void Main(string[] args)
    {
        Console.WriteLine("Hello NInject!");

        // TODO: Implement Functionality Here

        Kernel = new StandardKernel(new NjModule());
        Kernel.Settings.ActivationCacheDisabled = true;

        var requester = Kernel.Get<Requester>();

        for (int i = 0; i < 100000000; i++) {

            List<IMyObj> list =
                requester.RequestObjects();

            foreach (MyObj listItem in list) {
                listItem.Dispose();
            }
            list.Clear();
            list = null;

        }

        Console.Write("Press any key to continue . . . ");
        Console.ReadKey(true);
    }
}

Answer 1

I fixed the problem with memory by using ChildKernel. At the moment, I can't say anything about performance, however the memory leak is definitely fixed: the project started at 10MB and works on 15-25MB. Anyway, I'd be glad to consider other alternatives to my solution if you, the stackoverflowers, have such. My solution is here ( Github ) and the below:

public interface IMyObj : IDisposable
{
    string Name { get; set; }
}

public class MyObj : IMyObj
{
    public virtual string Name { get; set; }

    public virtual void Dispose()
    {
        Name = string.Empty;
        GC.SuppressFinalize(this);
    }
}

public class NjModule : NinjectModule
{
    public override void Load()
    {
        Bind<Requester>()
            .ToSelf()
            .InSingletonScope();

        Bind<IChildKernel>().ToSelf().InSingletonScope();
    }
}

public class NjChildKernelModule : NinjectModule
{
    public override void Load()
    {
        Bind<IMyObj>()
            .To<MyObj>()
            .InCallScope();
    }
}

public class Requester
{
    public List<IMyObj> RequestObjects(IChildKernel childKernel)
    {
        List<IMyObj> list = new List<IMyObj>();

        for(int i = 0; i < 10; i++) {
            var myObj = childKernel.Get<IMyObj>();
            myObj.Name = "abcdefghijklmnopqrstuvwxyz";
            list.Add(myObj);
        }

        return list;
    }
}

class Program
{
    public static IKernel Kernel;

    public static void Main(string[] args)
    {
        Console.WriteLine("Hello NInject!");

        // TODO: Implement Functionality Here

        Kernel = new StandardKernel(new NjModule());
        Kernel.Settings.ActivationCacheDisabled = true;

        var requester = Kernel.Get<Requester>();

        for (int i = 0; i < 100000000; i++) {

            var childKernel = new ChildKernel(Kernel, new NjChildKernelModule());
            childKernel.Settings.ActivationCacheDisabled = true;

            List<IMyObj> list =
                requester.RequestObjects(childKernel);

            foreach (MyObj listItem in list) {
                listItem.Dispose();
            }
            list.Clear();
            list = null;

            childKernel.Dispose();
        }

        Console.Write("Press any key to continue . . . ");
        Console.ReadKey(true);
    }
}

Answer 2

If think there is a misconception here. I think InCallScope is not doing what you think it is. Have a look at the following integration test for InCallScope :

this.kernel.Bind<Parent>().ToSelf();
this.kernel.Bind<Child>().ToSelf().InCallScope();
this.kernel.Bind<IGrandChild>().To<GrandChild>().InCallScope();

var parent1 = this.kernel.Get<Parent>();
var parent2 = this.kernel.Get<Parent>();
parent1.Dispose();

parent1.FirstChild.Should().BeSameAs(parent1.SecondChild);
parent1.GrandChild.Should().BeSameAs(parent1.FirstChild.GrandChild);
parent1.FirstChild.Should().NotBeSameAs(parent2.FirstChild);
parent1.GrandChild.Should().NotBeSameAs(parent2.GrandChild);

parent1.FirstChild.IsDisposed.Should().BeTrue();
parent1.FirstChild.GrandChild.IsDisposed.Should().BeTrue();
parent2.FirstChild.IsDisposed.Should().BeFalse();
parent2.FirstChild.GrandChild.IsDisposed.Should().BeFalse();

parent2.Dispose();
parent2.FirstChild.IsDisposed.Should().BeTrue();
parent2.FirstChild.GrandChild.IsDisposed.Should().BeTrue();

(Source: https://github.com/ninject/ninject.extensions.namedscope/blob/master/src/Ninject.Extensions.NamedScope.Test/NamedScopeIntegrationTest.cs )

As you can see the IChild is instantiated in the scope of Parent . IChild is disposed as soon as Parent is disposed.

In your example, Requester is bound InSingletonScope . Everything which is instantiated for / by Requester in its InChildScope will only be disposed once Requester is disposed. However, since you don't seem to be using ContextPreservation in your original Requester there is actually not even a scope for your IMyObj .

How would you like it to work?