ASP.NET MVC WebApi:没有为此对象定义的无参数构造函数

时间:2012-08-31 14:40:30

标签: asp.net-mvc asp.net-web-api ninject unit-of-work

我有一个ASP.NET MVC 4应用程序,我想实现工作单元模式。

在我的网络项目中,我有:

IocConfig.cs

using System.Web.Http;
using NinjectMVC.Data;
using NinjectMVC.Data.Contracts;
using Ninject;


namespace NinjectMVC
{
    public class IocConfig
    {
        public static void RegisterIoc(HttpConfiguration config)
        {
            var kernel = new StandardKernel(); // Ninject IoC

            // These registrations are "per instance request".
            // See http://blog.bobcravens.com/2010/03/ninject-life-cycle-management-or-scoping/

            kernel.Bind<RepositoryFactories>().To<RepositoryFactories>()
                .InSingletonScope();

            kernel.Bind<IRepositoryProvider>().To<RepositoryProvider>();
            kernel.Bind<INinjectMVCUow>().To<NinjectMVCUow>();

            // Tell WebApi how to use our Ninject IoC
            config.DependencyResolver = new NinjectDependencyResolver(kernel);
        }
    }
}

Global.asax中

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Http;
using System.Web.Mvc;
using System.Web.Optimization;
using System.Web.Routing;

namespace NinjectMVC
{
    // Note: For instructions on enabling IIS6 or IIS7 classic mode, 
    // visit http://go.microsoft.com/?LinkId=9394801

    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            // Tell WebApi to use our custom Ioc (Ninject)
            IocConfig.RegisterIoc(GlobalConfiguration.Configuration);   

            WebApiConfig.Register(GlobalConfiguration.Configuration);
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
            AuthConfig.RegisterAuth();
        }
    }
}

PersonsController.cs

using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using NinjectMVC.Data.Contracts;
using NinjectMVC.Model;

namespace NinjectMVC.Controllers
{
    public class PersonsController : ApiControllerBase
    {
        public PersonsController(INinjectMVCUow uow)
        {
            Uow = uow;
        }

        #region OData Future: IQueryable<T>
        //[Queryable]
        // public IQueryable<Person> Get()
        #endregion

        // GET /api/persons
        public IEnumerable<Person> Get()
        {
            return Uow.Persons.GetAll()
                .OrderBy(p => p.FirstName);
        }

        // GET /api/persons/5
        public Person Get(int id)
        {
            var person = Uow.Persons.GetById(id);
            if (person != null) return person;
            throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.NotFound));
        }

        // OData: GET /api/persons/?firstname=\'Hans\''
        // With OData query syntax we would not need such methods
        // /api/persons/getbyfirstname?value=Joe1
        [ActionName("getbyfirstname")]
        public Person GetByFirstName(string value)
        {
            var person = Uow.Persons.GetAll()
                .FirstOrDefault(p => p.FirstName.StartsWith(value));

            if (person != null) return person;
            throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.NotFound));
        }

        // Update an existing person
        // PUT /api/persons/
        public HttpResponseMessage Put(Person person)
        {
            Uow.Persons.Update(person);
            Uow.Commit();
            return new HttpResponseMessage(HttpStatusCode.NoContent);
        }

    }
}

当我尝试冲浪时:http://www.domain.com/Persons/Get我得到了:

没有为此对象定义无参数构造函数。

我错过了什么东西吗?我将不胜感激任何帮助。

以下是项目的zip文件,以便更好地参考:

http://filebin.ca/E6aoOkaUpbQ/NinjectMVC.zip

2 个答案:

答案 0 :(得分:8)

Wep.API使用与MVC框架不同的IDependencyResolver

使用HttpConfiguration.DependencyResolver时,它仅适用于ApiControllers。但是您的ApiControllerBase来自Controller ...

因此,ApiControllerBase应继承自ApiController

在ApiBaseController.cs中更改它:

public abstract class ApiControllerBase : ApiController
{
}

如果要将依赖项注入常规Controller派生类,则需要使用(在IocConfig中):

System.Web.Mvc.DependencyResolver.SetResolver(new NinjectMvcDependencyResolver(container));

请注意,在这种情况下,您无法使用NinjectDependencyResolver,因为它适用于ApiControllers

因此,您需要一个不同的NinjectMvcDependencyResolver来实现System.Web.Mvc.IDependencyResolver

public class NinjectMvcDependencyResolver: NinjectDependencyScope,
                                           System.Web.Mvc.IDependencyResolver
{
    private IKernel kernel;

    public NinjectDependencyResolver(IKernel kernel)
        : base(kernel)
    {
        this.kernel = kernel;
    }
}

答案 1 :(得分:1)

我知道这是一个旧线程,但这可能对某人有用。 :) 就我而言,它错过了DependencyResolver上的NinjectWebCommon.cs。 我遵循了这个article,一切正常。

RegisterServices(kernel);
GlobalConfiguration.Configuration.DependencyResolver = new NinjectDependencyResolver(kernel);
return kernel;