确保控制器有一个使用 Ninject 的无参数公共构造函数

Question

这是当前的问题：

通过URL 调用我的CustomerController 时，出现以下异常：

异常消息：

尝试创建类型控制器时出错 '客户控制器'。确保控制器具有 无参数的公共构造函数。

我正在使用以下网址：

• http://localhost:55555/api/Customer/
• http://localhost:55555/api/Customer/8

请注意：在我将逻辑重构为业务类并实施依赖注入之前，/api/Customer/ 调用正在工作。

我的研究表明我没有使用Ninject 正确注册我的接口和类，但不确定我缺少哪一步。

研究链接：

• Make sure that the controller has a parameterless public constructor error
• Make sure that the controller has a parameterless public constructor in Unity

这是我的问题是什么导致了这个异常？我正在Ninject 中注册我的接口/类，但它似乎无法正确识别映射。有什么想法吗？

客户控制器

public class CustomerController : ApiController
{
    private readonly ICustomerBusiness _customerBusiness;

    public CustomerController(ICustomerBusiness customerBusiness)
    {
        _customerBusiness = customerBusiness;
    }

    // GET api/Customer
    [HttpGet]
    public IEnumerable<Customer> GetCustomers()
    {
        return _customerBusiness.GetCustomers();
    }

    // GET api/Customer/Id
    [HttpGet]
    public IEnumerable<Customer> GetCustomersById(int customerId)
    {
        return _customerBusiness.GetCustomerById(customerId);
    }
}

客户业务

public class CustomerBusiness : ICustomerBusiness
{
    private readonly DatabaseContext _databaseContext = new DatabaseContext();

    public IEnumerable<Customer> GetCustomers()
    {
        return _databaseContext.Customers;
    }

    public IQueryable<Customer> GetCustomerById(int customerId)
    {
        return _databaseContext.Customers.Where(c => c.CustomerId == customerId);
    }       
}

客户业务界面

public interface ICustomerBusiness
{
    IQueryable<Customer> GetCustomerById(int customerId);
    IEnumerable<Customer> GetCustomers();
}

NinjectWebCommon

using System;
using System.Web;
using Microsoft.Web.Infrastructure.DynamicModuleHelper;
using MyReservation.API;
using MyReservation.API.Business;
using Ninject;
using Ninject.Web.Common;

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

namespace MyReservation.API
{
    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<ICustomerBusiness>().To<CustomerBusiness>();
        }        
    }
}

Answer 1

对于同样的问题，我安装了 nuget 包

• 注射

• ninject.web.common

• ninject.web.common.webhost

• ninject.web.webapi

• ninject.web.webapi.webhost

  工作过