当超出范围时，Ninject 不会对对象调用 Dispose [英] Ninject doesn't call Dispose on objects when out of scope

问题描述

我惊讶地发现，当 Ninject 创建的对象被定义为 InRequestScope 时，至少有一个我的对象在请求结束时没有被处理

I was surprised to find that at least one of my objects created by Ninject is not disposed of at the end of the request, when it has been defined to be InRequestScope

这是我要处理的对象:

界面:

public interface IDataContext : IDisposable
{
    MessengerEntities context { get; set; }
}

MessengerEntities 是实体框架对 ObjectContext 的实现——我的上下文对象.

MessengerEntities is Entity Framework's implementation of ObjectContext -- my context object.

然后我像这样创建一个具体的类:

Then I create a concrete class like so:

public class DataContext : IDataContext
{
    private MessengerEntities _context = new MessengerEntities();
    public MessengerEntities context
    {
        get
        {
            return _context;
        }
        set
        {
            _context = value;
        }
    }
    #region IDisposable Members

    public void Dispose()
    {
        context.Dispose();
    }

    #endregion
}

然后我有一个像这样的 Ninject 控制器工厂(这是模仿 Steve Sanderson MVC 2 的书):

And then I have a Ninject controller factory like so (this is modeled on the Steve Sanderson MVC 2 book):

public class NinjectControllerFactory : DefaultControllerFactory
{
    // a Ninject "kernel" is the thing that can supply object instances
    private IKernel kernel = new StandardKernel(new MessengerServices());

    // ASP.NET MVC calls this to get the controller for each request
    protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
    {
        if (controllerType == null)
            return null;
        return (IController)kernel.Get(controllerType);
    }

    private class MessengerServices : NinjectModule
    {
        public override void Load()
        {
            Bind<IDataContext>().To<DataContext>().InRequestScope();
            Bind<IArchivesRepository>().To<ArchivesRepository>().InRequestScope();
            Bind<IMessagesRepository>().To<MessagesRepository>().InRequestScope();
        }
    }
}

现在，当我在 DataContext 对象中对 context.Dispose() 的调用处设置断点并运行调试器时，该代码永远不会被执行.

Now, when I put a breakpoint at the call to context.Dispose() in the DataContext object and run the debugger, that code never gets executed.

因此，有证据表明，当对象超出范围时，Ninject 不会处理它们，而是简单地创建新对象并依靠垃圾收集器在其选择的时间清除它们.

So, the evidence suggests that Ninject does not dispose of objects when they go out of scope, but simply creates new objects and relies on the garbage collector to get rid of them at a time of its choosing.

我的问题是:我应该关心这个吗?因为我 - 我认为 Ninject 会处理任何实现 IDisposable 的对象.

My question is: should I be concerned about this? Because I am -- I would think Ninject would dispose of any object that implements IDisposable.

更新:我下载了 Ninject Mvc 扩展(用于 MVC 3)，这就是我现在如何进行 MvcApplication 和绑定，它似乎正在处理我的上下文对象.

UPDATE: I downloaded the Ninject Mvc extensions (for MVC 3) and this is now how I'm doing the MvcApplication and the binding, and it does seem to be disposing of my context object.

在 global.asax 中:

In global.asax:

public class MvcApplication : NinjectHttpApplication
{
    public static void RegisterGlobalFilters(GlobalFilterCollection filters)
    {
        filters.Add(new HandleErrorAttribute());
    }

    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

        routes.MapRoute(
            "Default", // Route name
            "{controller}/{action}/{id}", // URL with parameters
            new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
        );

    }

    protected override Ninject.IKernel CreateKernel()
    {
        var kernel = new StandardKernel();
        kernel.Load(Assembly.GetExecutingAssembly());
        return kernel;
    }

    protected override void OnApplicationStarted()
    {
        base.OnApplicationStarted();
        AreaRegistration.RegisterAllAreas();
        RegisterGlobalFilters(GlobalFilters.Filters);
        RegisterRoutes(RouteTable.Routes);
    }
}

和

public class EFBindingModule : NinjectModule
{
    public override void Load()
    {
        Bind<IDataContext>().To<DataContext>().InRequestScope();
        Bind<IArchivesRepository>().To<ArchivesRepository>().InRequestScope();
        Bind<IMessagesRepository>().To<MessagesRepository>().InRequestScope();
    }
}

其他一切都保持不变.

推荐答案

Ninject 将在 GC 收集到请求对象后立即处理您的对象.但通常这需要一些时间.但是有一种方法可以在请求结束后强制提前处理.最好的方法是使用 Ninject.Web.MVC http://www.planetgeek.ch/2010/11/13/official-ninject-mvc-extension-gets-support-for-mvc3/ 而不是实现您自己的 ControllerFactory.另一种方法是将您的应用程序配置为使用 OnePerRequestModule.

Ninject will dispose your objects as soon as the request object is collected by the GC. But normally this takes some time. But there is a way to force early disposal after the request ended. The best way is to use Ninject.Web.MVC http://www.planetgeek.ch/2010/11/13/official-ninject-mvc-extension-gets-support-for-mvc3/ instead of implementing your own ControllerFactory. The other way is to configure your application to use the OnePerRequestModule.

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