错误 occurred.Type 'my api name controller' 在 System.Linq.Expressions.Expression 处没有默认值 constructorSystem.ArgumentException

Question

我正在尝试使用 angular 创建一个 mvc 项目。所以我创建了一个 api controller，如您在此处所见：

namespace MvcApplication3.Controllers
{
    public class TopicsController : ApiController
    {
        private IMessageBoardRepository _repo;
        public TopicsController(IMessageBoardRepository repo)
        {
            _repo = repo;
        }

        public IEnumerable<Topic> Get(bool includeReplies = false)
        {
            IQueryable<Topic> results;

            if (includeReplies == true)
            {
                results = _repo.GetTopicsIncludingReplies();
            }
            else
            {
                results = _repo.GetTopics();
            }

            var topics = results.OrderByDescending(t => t.Created)
                                .Take(25)
                                .ToList();

            return topics;
        }

        // I didn't show this, but this is common
        public HttpResponseMessage Get(int id, bool includeReplies = false)
        {
            IQueryable<Topic> results;

            if (includeReplies == true)
            {
                results = _repo.GetTopicsIncludingReplies();
            }
            else
            {
                results = _repo.GetTopics();
            }

            var topic = results.Where(t => t.Id == id).FirstOrDefault();

            if (topic != null) return Request.CreateResponse(HttpStatusCode.OK, topic);

            return Request.CreateResponse(HttpStatusCode.NotFound);
        }
}
}

我正在使用 ninject 3.2.1.0 将我的界面绑定到它的存储库。

   private static void RegisterServices(IKernel kernel)
        {
            kernel.Bind<MessageBoardContext>().To<MessageBoardContext>().InRequestScope();
            kernel.Bind<IMessageBoardRepository>().To<MessageBoardRepository>().InRequestScope();
        }

但是当我用这个 api 调用这个 url 时：http://localhost:53005/api/v1/topics 我收到这个错误：

    An error has occurred.Type 'MvcApplication3.Controllers.TopicsController' does not have a default constructorSystem.ArgumentException   at System.Linq.Expressions.Expression.New(Type type)
   at System.Web.Http.Internal.TypeActivator.Create[TBase](Type instanceType)
   at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.GetInstanceOrActivator(HttpRequestMessage request, Type controllerType, Func`1& activator)
   at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)

Answer 1

最后我应该安装 WebApiContrib.IoC.Ninject nuget 并将此解析器添加到 ninjectwebcommen 文件中，如您在此处所见：

   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);
                GlobalConfiguration.Configuration.DependencyResolver =
       new NinjectResolver(kernel);
                return kernel;
            }
            catch
            {
                kernel.Dispose();
                throw;
            }
        }