确保控制器有一个无参数的公共构造函数

我已经研究了一些基于消息的错误"确保控制器有一个无参数的公共构造函数"和这些答案似乎没有帮助。(见底)

构建一个ASP。. NET WEB API 2应用程序使用Ninject。我想要一个applicationController，它将从Angular服务中轮询，以允许跨会话共享一些信息。为了实现这一点，我构建了一个applicationService，设计成作为一个单例运行，这样每个web api会话将共享相同的服务。我正在使用Ninject 3.2.0.0并已安装(根据这些说明使用NPM)

• Ninject
• Ninject.Web。常见的
• Ninject.Web.WebApi
• Ninject.Web.WebApi.WebHost

按照设计，创建了我添加(我相信)必要绑定的NinjectWebCommon。在初始请求期间，applicationService被实例化(如预期的那样)，但是当调用applicationController的GET方法时，我得到:

创建类型为的控制器时发生错误"控制器"。确保控制器有无参数公共构造函数。

堆栈跟踪显示:

在System.Linq.Expressions.Expression

。新(类型类型)在System.Web.Http.Internal.TypeActivator.Create [TBase](类型instanceType)System.Web.Http.Dispatcher.DefaultHttpControllerActivator.GetInstanceOrActivator (HttpRequestMessage请求，类型controllerType, Func ' 1&激活)System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create (HttpRequestMessageHttpControllerDescriptor, TypecontrollerType)

它调用DefaultHttpControllerActivator的事实使我认为Ninject绑定是不正确的，但是applicationService可以实例化的唯一方法是由于Ninject。

NinjectWebCommon

    private static void RegisterServices(IKernel kernel)
   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<ScfProvider>().ToSelf().InSingletonScope();
            kernel.Bind<ApplicationService>().ToSelf().InSingletonScope().WithConstructorArgument(kernel.Get<ScfProvider>());
            kernel.Bind<ApplicationController>().ToSelf().InRequestScope().WithConstructorArgument(kernel.Get<ApplicationService>());
        }        
    }

ApplicationService :

    public sealed class ApplicationService
    {
        private readonly ICommand _scfUpdater;
        private Timer _timer;
        public ApplicationService(ScfProvider scfUpdater)
        {
            if (scfUpdater == null) throw new ArgumentNullException(nameof(scfUpdater));
            _scfUpdater = scfUpdater;
            _activeUsers = new Dictionary<string, string>();
            int scfInterval = int.Parse(ConfigurationManager.AppSettings["SCFUpdateInterval"]);
            _timer = new Timer(SCFTick, this, 0, scfInterval);
        }
#if DEBUG
        public ICommand SCFUpdater => _scfUpdater;
#endif

        private void SCFTick(object state)
        {
            _scfUpdater.Execute();
        }
        private readonly Dictionary<string, string> _activeUsers;
        public Dictionary<string, string> ActiveUsers => _activeUsers;
        public void UpdateUser(string userName, string status)
        {
            if (_activeUsers.ContainsKey(userName))
            {
                _activeUsers[userName] = status;
            }
            else
            {
                _activeUsers.Add(userName, status);
            }
        }
}

最后是applicationController:

public class ApplicationController : ApiController

 {
        private readonly ApplicationService _applicationService;
        public ApplicationController(ApplicationService applicationService)
        {
            _applicationService = applicationService;
        }
        // GET: api/application
        public IHttpActionResult Get()
        {
            _applicationService.UpdateUser(User.Identity.Name, "online");
            return Ok(_applicationService.ActiveUsers);
        }
...
}

(注意:一旦我有这个工作更复杂的功能将被添加…但我需要这个先工作…)

其他研究:.NET Web Api 2.1中使用Ninject绑定的无参数构造函数错误(我有正确的引用和公共c'tor)

Ninject Web Api "确保控制器有一个无参数的公共构造函数"(,几个类似的)(据我所知，WebActivatorEx和NinjectWebCommon解决了这个问题)