我试图在 Controller 中注入(inject)几个类,但失败了。
这就是我所做的:
- 添加了
Ninject.Web.WebApi.WebHost
和WebActivatorEx
NuGet 包 - 在
App_Start
下创建了以下类:
NinjectWebCommon.cs
using Microsoft.Web.Infrastructure.DynamicModuleHelper;
using Ninject;
using Ninject.Web.Common;
using Ninject.Web.Common.WebHost;
using MyProject;
using MyProject.Models;
using MyProject.Classes;
using System;
using System.Web;
[assembly: WebActivatorEx.PreApplicationStartMethod(typeof(NinjectWebCommon), "Start")]
[assembly: WebActivatorEx.ApplicationShutdownMethodAttribute(typeof(NinjectWebCommon), "Stop")]
namespace MyProject
{
public static class NinjectWebCommon
{
private static readonly Bootstrapper bootstrapper = new Bootstrapper();
public static void Start()
{
DynamicModuleUtility.RegisterModule(typeof(OnePerRequestHttpModule));
DynamicModuleUtility.RegisterModule(typeof(NinjectHttpModule));
bootstrapper.Initialize(CreateKernel);
}
public static void Stop()
{
bootstrapper.ShutDown();
}
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
RegisterServices(kernel);
return kernel;
}
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<IMyContext>().ToSelf().InRequestScope();
kernel.Bind<IErp>().ToSelf().InRequestScope();
}
}
}
- 创建了我的类(class):
MyContext.cs:
using MyProject.Models;
using System;
using System.Data.Entity;
using System.Data.Entity.ModelConfiguration.Conventions;
using System.Threading.Tasks;
namespace MyProject.Models
{
public interface IMyContext : IDisposable
{
DbSet<Operator> Operators { get; set; }
Task<int> SaveChangesAsync();
}
public class MyContext : DbContext, IMyContext
{
public MyContext () : base("MyContext ") { }
public DbSet<Operator> Operators { get; set; }
public async override Task<int> SaveChangesAsync()
{
return await SaveChangesAsync(CancellationToken.None);
}
}
}
Erp.cs
public interface IErp
{
Task ImportListAsync();
}
public class Erp : IErp
{
private readonly IMyContext _context;
public Erp(IMyContext context)
{
_context = context;
}
public async Task ImportListAsync()
{
// do something
}
}
创建了一个 Controller
using MyProject.Classes; using MyProject.Models; using System.Data.Entity; using System.Threading.Tasks; using System.Web.Mvc; namespace MyProject.Controllers { public class OperatorsController : Controller { private readonly IMyContext _context; private readonly IErp _erp; public OperatorsController(IMyContext context, Erp Ierp) { _context = context; _erp = erp; } // GET: Operators public async Task<ActionResult> Index() { return View(await _context.Operators.ToListAsync()); } // GET: Operators/Import public async Task<ActionResult> Import() { await _erp.ImportListAsync(); return View("Index", await _context.Operators.ToListAsync()); } } }
但是当我运行该应用程序时,我仍然收到有关缺少无参数构造函数的臭名昭著的错误。这对我来说 DI 不起作用。
最佳答案
我相信您在RegisterServices
中的注册调用是错误的 - 您无法绑定(bind)接口(interface).ToSelf()
-您需要将接口(interface)绑定(bind)到具体类 实现它 - 像这样:
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<IMyContext>().To<MyContext>().InRequestScope();
kernel.Bind<IErp>().To<Erp>().InRequestScope();
}
这样,只要在代码中需要 IMyContext
依赖项,您就可以告诉 DI 容器实例化 MyContext
类
关于c# - MVC5 和 Ninject 的依赖注入(inject)失败,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/47724068/