在 Global.asax 中註入依賴項

我正在使用 MVC3 和 Ninject 啟動一個 Web 應用程序。在 Global.asax 文件中我還需要一個依賴項，它需要是一個單例。

我認為它應該是這樣的：

public class MvcApplication : NinjectHttpApplication
{
   IUserAuthentication _auth;

   public MvcApplication()
   {
       base.AuthenticateRequest += new EventHandler(MvcApplication_AuthenticateRequest);
   }

   protected override IKernel CreateKernel()
   {
       var _kernel = new StandardKernel(new SecurityModule());
       _auth = _kernel.Get<IUserAuthentication>();

       return _kernel;
   }

   void MvcApplication_AuthenticateRequest(object sender, EventArgs e)
   {
       _auth.ToString();
   }

但是後來我看到它在被呼叫_auth時為空MvcApplication_AuthenticateRequest。

然後我嘗試這樣：

public class MvcApplication : NinjectHttpApplication
{
   ItUserAuthentication _auth;
   IKernel _kernel;

   public MvcApplication()
   {
       _kernel = new StandardKernel(new SecurityModule());
       _auth = _kernel.Get<IUserAuthentication>();
       base.AuthenticateRequest += new EventHandler(MvcApplication_AuthenticateRequest);
   }

   protected override IKernel CreateKernel()
   {
       return _kernel;
   }

   void MvcApplication_AuthenticateRequest(object sender, EventArgs e)
   {
       _auth.ToString();
   }

但是現在我可以看到建構子被多次呼叫，因此我將有幾個 IKernel，我猜單例實例在我的應用程序範圍內不會那麼單例。

我該怎麼做？使用靜態變數？

我們就是這樣做的，我做了一些測試，我的 AuthService 似乎只進入了他的控制器一次：

public class MvcApplication : NinjectHttpApplication
   {

       public static void RegisterRoutes(RouteCollection routes)
       {
           routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

           routes.MapRoute(
               "Default", // Route name
               "{controller}/{action}/{id}", // URL with parameters
               new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
           );

       }

       protected override IKernel CreateKernel()
       {
           var kernel = new StandardKernel();
           kernel.Load(Assembly.GetExecutingAssembly());

           kernel.Bind<ISession>().To<MongoSession>().InRequestScope();
           kernel.Bind<IAuthenticationService>().To<AuthenticationService>().InSingletonScope();
           kernel.Bind<IMailer>().To<Mailer>().InRequestScope();
           kernel.Bind<IFileProvider>().To<MongoFileProvider>().InRequestScope();

           return kernel;
       }

       protected override void OnApplicationStarted()
       {
           base.OnApplicationStarted();

           AreaRegistration.RegisterAllAreas();
           RegisterRoutes(RouteTable.Routes);
       }

       protected void Application_AuthenticateRequest(Object sender, EventArgs e)
       {
           if (HttpContext.Current.User != null)
           {
               if (HttpContext.Current.User.Identity.IsAuthenticated)
               {
                   if (HttpContext.Current.User.Identity is FormsIdentity)
                   {
                       var id = (FormsIdentity) HttpContext.Current.User.Identity;
                       var ticket = id.Ticket;
                       var authToken = ticket.UserData;
                       var authService = (IAuthenticationService)DependencyResolver.Current.GetService(typeof(IAuthenticationService));
                       var user = authService.GetUserForAuthToken(authToken);
                       if (user != null)
                       {
                           user.SetIdentity(HttpContext.Current.User.Identity);
                           HttpContext.Current.User = (IPrincipal) user;
                       }
                   }
               }
           }
       }
}

希望能幫助到你！

引用自：https://stackoverflow.com/questions/5512040