Ninject InSingletonScope与网页API RC [英] Ninject InSingletonScope with Web Api RC

问题描述

我在使用Ninject的InSingletonScope与网页API RC结合一定的难度。无论我如何创建我的结合，看起来也许网页API正在处理，而不是Ninject范围/寿命。

I'm having some difficulty using Ninject's InSingletonScope binding with Web Api RC. No matter how I create my binding, it looks like perhaps Web Api is handling scope/lifetime instead of Ninject.

我试过在连接最多Ninject有一些变化。最常见的是与此处的答案：
mvc4 RC的WebAPI与ninject

I've tried a few variations on wiring up Ninject. The most common is identical to the answer here: mvc4 rc webapi binding with ninject

我也试过这个版本：
<一href=\"http://www.peterprovost.org/blog/2012/06/19/adding-ninject-to-web-api/\">http://www.peterprovost.org/blog/2012/06/19/adding-ninject-to-web-api/

在这两个，我硬是​​创造一个现成的Web API项目中，然后加入Ninject包中任一职位描述。最后，我添加了Resolver和范围类，如本作的StackOverflow的版本：

In both, I'm literally creating an out of the box Web Api project, then adding the Ninject packages as described in either post. Finally, I'm adding the Resolver and Scope classes, such as this for the StackOverflow version:

public class NinjectDependencyScope : IDependencyScope
{
    private IResolutionRoot resolver;

    internal NinjectDependencyScope(IResolutionRoot resolver)
    {
        Contract.Assert(resolver != null);

        this.resolver = resolver;
    }

    public void Dispose()
    {
        IDisposable disposable = resolver as IDisposable;
        if (disposable != null)
            disposable.Dispose();

        resolver = null;
    }
    public object GetService(Type serviceType)
    {
        if (resolver == null)
            throw new ObjectDisposedException("this", "This scope has already been disposed");
        return resolver.TryGet(serviceType);
    }

    public IEnumerable<object> GetServices(Type serviceType)
    {
        if (resolver == null)
            throw new ObjectDisposedException("this", "This scope has already been disposed");
        return resolver.GetAll(serviceType);
    }
}

和

 public class NinjectDependencyResolver : NinjectDependencyScope, IDependencyResolver
{
    private IKernel kernel;

    public NinjectDependencyResolver(IKernel kernel)
        : base(kernel)
    {
        this.kernel = kernel;
    }
    public IDependencyScope BeginScope()
    {
        return new NinjectDependencyScope(kernel.BeginBlock());
    }
}

然后，NinjectWebCommon看起来是这样的：

Then, NinjectWebCommon looks like this:

using System.Web.Http;
using MvcApplication2.Controllers;

[assembly: WebActivator.PreApplicationStartMethod(typeof(MvcApplication2.App_Start.NinjectWebCommon), "Start")]
[assembly: WebActivator.ApplicationShutdownMethodAttribute(typeof(MvcApplication2.App_Start.NinjectWebCommon), "Stop")]

namespace MvcApplication2.App_Start
{
    using System;
    using System.Web;

    using Microsoft.Web.Infrastructure.DynamicModuleHelper;

    using Ninject;
    using Ninject.Web.Common;

    public static class NinjectWebCommon
    {
        private static readonly Bootstrapper bootstrapper = new Bootstrapper();

        /// <summary>
        /// Starts the application
        /// </summary>
        public static void Start()
        {
            DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
            DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
            bootstrapper.Initialize(CreateKernel);
        }

        /// <summary>
        /// Stops the application.
        /// </summary>
        public static void Stop()
        {
            bootstrapper.ShutDown();
        }

        /// <summary>
        /// Creates the kernel that will manage your application.
        /// </summary>
        /// <returns>The created kernel.</returns>
        private static IKernel CreateKernel()
        {
            var kernel = new StandardKernel();
            kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
            kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();

            // Register Dependencies
            RegisterServices(kernel);

            // Set Web API Resolver
            GlobalConfiguration.Configuration.DependencyResolver = new NinjectDependencyResolver(kernel);

            return kernel;
        }

        /// <summary>
        /// Load your modules or register your services here!
        /// </summary>
        /// <param name="kernel">The kernel.</param>
        private static void RegisterServices(IKernel kernel)
        {
            kernel.Bind<ILogger>().To<Logger>().InSingletonScope();
        }
    }
}

该ILogger和Logger对象没有做任何事情，但说明问题。记录仪做的Debug.WriteLine，这样我可以看到，当它被实例化。和页面的每次刷新表明，它正在每次呼叫刷新，而不是我希望的单身。下面是使用记录器的控制器：

The ILogger and Logger objects don't do anything, but illustrate the issue. Logger does Debug.Writeline so that I can see when it was instantiated. And each refresh of the page shows that it's being refreshed per call, rather than the singleton I'd hoped for. Here is a controller using the Logger:

public class ValuesController : ApiController
{
    private readonly ILogger _logger;
    public ValuesController(ILogger logger)
    {
        _logger = logger;
        _logger.Log("Logger created at " + System.DateTime.Now.ToLongTimeString());
    }
    // GET api/values
    public IEnumerable<string> Get()
    {
        return new string[] { "value1", "value2" };
    }
    // GET api/values/5
    public string Get(int id)
    {
        return "value";
    }
    // POST api/values
    public void Post(string value)
    {
    }
    // PUT api/values/5
    public void Put(int id, string value)
    {
    }
    // DELETE api/values/5
    public void Delete(int id)
    {
    }
}

当我把跟踪信息到创作的内核，它似乎表明，内核只创建一次。所以......那我没有看到？为什么不坚持单身？

When I put trace information into the creation of the kernel, it seems to show that the kernel is only created once. So... what am I not seeing? Why isn't the singleton persisted?

推荐答案

使用

public IDependencyScope BeginScope()
{
    return new NinjectDependencyScope(kernel);
}

和不处理内核的 NinjectDependencyScope

这篇关于Ninject InSingletonScope与网页API RC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！