在Global.asax中创建一个绑定依赖于HttpContext的Ninject内核

Question

创建我的内核时，我不断收到一个错误“System.Web.HttpException：请求在此上下文中不可用”。考虑到我的一个绑定依赖于上下文，这是有道理的。 Application_Start显然没有上下文。我只是想知道如果有人知道如何解决这个问题。

public class NinjectBindings : NinjectModule 
{ 
    public override void Load() 
    {  
     //Framework 
     Bind<IJsonLayer>().To<JsonLayer>(); 
     Bind<IBusinessLayer>().To<BusinessLayer>(); 

     //Controllers 
     Bind<ITeamController>().To<TeamController>(); 
    } 
} 


public class Global : System.Web.HttpApplication 
{ 
    protected void Application_Start(object sender, EventArgs e) 
    { 
     ReflectionUtility.Kernel = new StandardKernel(new NinjectBindings()); 
    } 
} 


public class ReflectionUtility 
{ 
    private static IKernel _kernel; 

    public static IKernel Kernel { 
     set { _kernel = value; } 
    } 
} 



public class JsonLayer : IJsonLayer 
{ 
    private readonly ITeamController _teamController; 
    private readonly IBusinessLayer _businessLayer; 

    public JsonLayer(ITeamController teamController, IBusinessLayer businessLayer) 
    { 
     _teamController = teamController; 
     _businessLayer = businessLayer; 
    } 
} 


public class BusinessLayer : IBusinessLayer 
{ 
    //this is a super-simplification of what's going on. there are multiple different calls to HttpContext.Current.Request in this class 
    public BusinessLayer() 
    { 
     //This is where it breaks 
     var sessionUserId = HttpContext.Current.Request.Headers["X-SessionUserId"]; 
    } 

} 

public class TeamController : ITeamController 
{ 
     public void DeleteTeam(int intTeam) 
     { 
      throw new NotImplementedException(); 
     } 
} 

Answer 1

做你想，从Business层访问HttpContext是好主意吗？也许你可以花一些时间重构？例如，像this之类的东西。

从应用的角度来看，你可以做这样的事情：

private void RegisterDependencyResolver() 
{ 
    kernel 
    .Bind<ISession>() 
    .To<SessionService>() 
    .InRequestScope() 
    .WithConstructorArgument(
     "context", 
     ninjectContext => new HttpContextWrapper(HttpContext.Current) 
    ); 

    DependencyResolver.SetResolver(new NinjectDependencyResolver(kernel)); 
}