问题描述
我开始在我的MVC5 code-第一个应用程序使用Ninject。这里是我的NinjectWebCommon.cs：
I am starting to use Ninject in my MVC5 code-first app. Here's my NinjectWebCommon.cs:
private static IKernel CreateKernel()
{
var kernel = new StandardKernel();
try
{
kernel.Bind<Func<IKernel>>().ToMethod(ctx => () => new Bootstrapper().Kernel);
kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>();
kernel.Bind<CMSContext>()
.ToSelf()
//.InSingletonScope();
.InRequestScope();
kernel.Bind<IExecutiveRepository>()
.To<ExecutiveRepository>();
kernel.Bind<IExecutiveSectionRepository>()
.To<ExecutiveSectionRepository>();
kernel.Bind<IExecutiveSectionMappingRepository>()
.To<ExecutiveSectionMappingRepository>();
kernel.Bind<IUserRepository>()
.To<UserRepository>();
kernel.Bind<IContentRepository>()
.To<ContentRepository>();
RegisterServices(kernel);
return kernel;
}
catch
{
kernel.Dispose();
throw;
}
}
我试过.InSingletonScope（）以及.InRequestScope（），但我仍然得到错误'的实体对象不能被IEntityChangeTracker的多个实例引用'。
这里是我的接口：
I tried .InSingletonScope() as well as .InRequestScope() but I still get the 'entity object cannot be referenced by multiple instances of IEntityChangeTracker' error.Here is my Interface:
public interface IExecutiveRepository : IDisposable
{
IEnumerable<Executive> GetExecutives();
Executive GetExecutiveById(int executiveId);
void InsertExecutive(Executive executive);
void UpdateExecutive(Executive executive);
void DeleteExecutive(int executiveId);
void Save();
}
下面是我的具体的：
public class ExecutiveRepository : IExecutiveRepository, IDisposable
{
private CMSContext context;
public ExecutiveRepository(CMSContext context)
{
this.context = context;
}
public IEnumerable<Executive> GetExecutives()
{
return context.Executives.ToList();
}
public Executive GetExecutiveById(int id)
{
return context.Executives.Find(id);
}
public void InsertExecutive(Executive executive)
{
context.Executives.Add(executive);
}
public void DeleteExecutive(int executiveId)
{
Executive executive = context.Executives.Find(executiveId);
context.Executives.Remove(executive);
}
public void UpdateExecutive(Executive executive)
{
context.Entry(executive).State = EntityState.Modified;
}
public void Save()
{
context.SaveChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
下面是控制器（顶部相关部分）：
Here is the controller(top pertinent part):
public class ExecutiveController : Controller
{
private IExecutiveRepository executiveRepository;
private IUserRepository userRepository;
private IExecutiveSectionRepository executiveSectionRepository;
private IExecutiveSectionMappingRepository executiveSectionMappingRepository;
private IContentRepository contentRepository;
private Ninject.IKernel _kernel = new StandardKernel();
//[Inject]
public ExecutiveController()
{
executiveRepository = _kernel.Get<ExecutiveRepository>();
userRepository = _kernel.Get<UserRepository>();
executiveSectionRepository = _kernel.Get<ExecutiveSectionRepository>();
executiveSectionMappingRepository = _kernel.Get<ExecutiveSectionMappingRepository>();
contentRepository = _kernel.Get<ContentRepository>();
}
...
不知道我做错了，但在添加一个新的'执行'吧......炸弹我明白它试图使用单独的环境，这就是这个问题，但我只是不知道如何解决它。显然，在NinjectWebCommon.cs类行：
Not sure what I am doing wrong but upon adding a new 'Executive' it bombs... I do understand it's trying to use separate contexts and that's the problem, but I 'm just not sure how to fix it. Apparently, the line in the NinjectWebCommon.cs class:
kernel.Bind<CMSContext>()
.ToSelf()
//.InSingletonScope();
.InRequestScope();
应该是修复，但它不是...
任何想法/建议？
Is supposed to be the fix, but it isn't...any ideas/suggestions?
推荐答案
您应该使用的NuGet包 Ninject.Web.Mvc 如果您还不是。这将配置您的应用程序就可以使用Ninject，除了你的绑定。看起来你是相当熟悉的东西绑定方已经从我可以在你的 CreateKernel（）办法看到的。
You should be using NUGET package Ninject.Web.Mvc if you aren't already. This configures your application ready to use Ninject, other than your bindings. It looks like you are reasonably familiar with the bindings side of things already from what I can see in your CreateKernel() method.
在您的绑定地方，你不应该在你的控制器来创建内核，这是因为 Ninject.Web.Mvc 库配置Ninject创建控制器，用于你引擎盖下。因此，您添加到他们的任何依赖关系应该会自动解决。
Once your bindings are in place, you should not be creating Kernels in your controllers, this is because the Ninject.Web.Mvc library configures Ninject to create your controllers for you under the hood. Therefore any dependencies that you add to them should be automatically resolved.
所以，你可以使用构造函数注入，以解决您的依赖关系：
So, you can use constructor injection to resolve your dependencies:
public class ExecutiveController : Controller
{
private IExecutiveRepository ExecutiveRepository;
private IUserRepository UserRepository;
private IExecutiveSectionRepository ExecutiveSectionRepository;
private IExecutiveSectionMappingRepository ExecutiveSectionMappingRepository;
private IContentRepository ContentRepository;
public ExecutiveController(
IExecutiveRepository executiveRepository,
IUserRepository userRepository,
IExecutiveSectionRepository executiveSectionRepository,
IExecutiveSectionMappingRepository executiveSectionMappingRepository,
IContentRepository contentRepository)
{
// Set the field values
this.ExecutiveRepository = executiveRepository,
this.UserRepository = userRepository,
this.ExecutiveSectionRepository = executiveSectionRepository,
this.ExecutiveSectionMappingRepository = executiveSectionMappingRepository,
this.ContentRepository = contentRepository;
}
public ActionResult Index(int id)
{
// Use one of your dependencies...
var executive = this.executiveRepository.GetExecutiveById(id);
}
}
或者你也可以使用具有相同的效果 [注入] 属性：
public class ExecutiveController : Controller
{
[Inject]
public IExecutiveRepository executiveRepository { get; set; }
[Inject]
public IUserRepository userRepository { get; set; }
[Inject]
public IExecutiveSectionRepository executiveSectionRepository { get; set; }
[Inject]
public IExecutiveSectionMappingRepository executiveSectionMappingRepository { get; set; }
[Inject]
public IContentRepository contentRepository { get; set; }
public ExecutiveController()
{
}
public ActionResult Index(int id)
{
// Use one of your dependencies...
var executive = this.executiveRepository.GetExecutiveById(id);
}
}
这篇关于Ninject：实体对象不能由IEntityChangeTracker的多个实例被引用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！