asp.net-mvc-5 - Ninject 不适用于 Asp.Net WebApi

Question

我见过很多人问这个问题，并尝试过他们接受的答案，但没有一个对我有用。

当我尝试将 Ninject 与我的 asp.net webapi 一起使用时，我不断收到此错误

 { "Message": "An error has occurred.", "ExceptionMessage": "An error
 occurred when trying to create a controller of type
 'SubjectPostsController'. Make sure that the controller has a
 parameterless public constructor.", "ExceptionType":
"System.InvalidOperationException", "StackTrace": " at
System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create
(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type
controllerType)\ \ at
System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage
request)\ \ at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext ()",
"InnerException": { "Message": "An error has occurred.",
"ExceptionMessage": "Type
'Analyzer.Controllers.SubjectPostsController' does not have a default
 constructor", "ExceptionType": "System.ArgumentException",
"StackTrace": " at System.Linq.Expressions.Expression.New(Type type)\
\ at System.Web.Http.Internal.TypeActivator.Create[TBase](Type
instanceType)\ \ atSystem.Web.Http.Dispatcher.DefaultHttpControllerActivator.GetInstanceOrActivator(HttpRequestMessage
request, Type controllerType, Func`1& activator)\ \ at  System.Web.Http.Dispatcher.DefaultHttpControllerActivator.CreateHttpRequestMessa ge
request, HttpControllerDescriptor controllerDescriptor, Type
controllerType)" } }

我的 Controller :

using Analyzer.Models.ModelsForApp;
using Analyzer.Repository;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;

namespace Analyzer.Controllers
{
    public class SubjectPostsController : ApiController
    {
        private IRepository _repo;
        public SubjectPostsController(IRepository repo)
        {
            _repo = repo;
        }
        public IEnumerable<SubjectPost> Get()
        {
            var posts = _repo.GetSubjectPosts()
           .OrderByDescending(p =>p.Created).ToList();
            return posts;

        }
    }
}

Ninject.WebCommon:

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

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

using Microsoft.Web.Infrastructure.DynamicModuleHelper;

using Ninject;
using Ninject.Web.Common;
using Analyzer.Database;
using Analyzer.Repository;
using System.Web.Http;


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();
        try
        {
            kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
            kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();

            RegisterServices(kernel);
            return kernel;
        }
        catch
        {
            kernel.Dispose();
            throw;
        }
    }

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

我安装的nuget包是:

Ninject version 3.2.2.0
Ninject integration for WepApi2 3.2.4.0
Ninject Web Host for WebApi2 3.2.4.0
Ninject.MVC3 3.2.1.0
Ninject.Web 3.2.1.0
Ninject.Web.Common 3.2.3.0
Ninject.Web.Common.WebHost 3.2.3.0
WebApiContrib.IoC.Ninject

到目前为止，我已经尝试了很多可能性，当我尝试该方法时，GlobalConfiguration.Configuration.DependencyResolver 抛出异常。

所以基本上，我的想法已经用完了。有谁知道如何解决这个问题？

更新:我尝试使用 Unity 解决这个问题并且成功了。虽然我不知道使用unity有什么弊端以及它得到的支持量(好像快一年没更新了)。正在研究更多关于 unity 的内容，但我仍然对使用 Ninject 的解决方案感兴趣。

更新 2:它也适用于 SimpleInjector...我开始认为问题出在 Ninject 上。谁能让 Ninject 与 WebApi 一起工作？

Answer 1

我使用以下内容:

    protected void Application_Start()
    {
        AreaRegistration.RegisterAllAreas();

        var dependencyInjectionProvider = new DependencyInjectionProvider();

        // Set MVC depencendy resolver for asp mvc web project
        DependencyResolver.SetResolver(dependencyInjectionProvider.GetMvcDependencyResolver());

        // Set MVC depencendy resolver for asp mvc web API project
        GlobalConfiguration.Configuration.DependencyResolver = dependencyInjectionProvider.GetHttpDependencyResolver();


        WebApiConfig.Register(GlobalConfiguration.Configuration);
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);
    }

DependencyInjectionProvider 有两个内部组件:

• HttpDependencyResolver 解决 ApiControlelrs 上的注入(inject)
• MvcDependencyResolver 解决 Mvc Controller 上的注入(inject)

您可以在 https://gist.github.com/remojansen/d907f8e2c2c4bfb7f65e 找到完整的实现