Reputation:
My project is using ASP.NET MVC and Ninject
to bind abstract interfaces to concrete implementations so my website Controllers
can fetch data. However, now I want to add the option of getting the same set of data from a different location. This will require a different implementation of the abstract interface I use, but all the method calls are the same. I still want to keep using Ninject, but I don't want to just copy the interface I already have and name it something different.
EDIT 1: I just realized I never formally asked a question. How do I tell Ninject
and/or the ASP.NET Controller Factories to use one implementation of an abstract class over another based solely on a query string?
Here's an example of what I'm talking about:
// Global.asax.cs
public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
// Using Ninject resolver
NinjectResolver.SetResolver(new NinjectResolver());
}
}
// NinjectResolver.cs
public class NinjectResolver : IDependencyResolver
{
private IKernel kernel;
public NinjectResolver()
{
kernel = new StandardKernel();
AddBindings();
}
public void AddBindings()
{
// I don't know what to do here:
//kernel.Bind<IFooModel>().To<FooModelImplementation>();
//kernel.Bind<IFooModel>().To<FooModelImplementation2>();
}
}
The interface implementation:
// FooModel.cs
public interface IFooModel
{
FooData GetData(int dataID);
}
public class FooData
{
public string Field1 {get; set;}
public string Field2 {get; set;}
public string Field3 {get; set;}
// ...
public FooData()
{ }
}
public class FooModelImplementation : IFooModel
{
public FooModelImplementation()
{ }
public FooData GetData(int dataID)
{
// Get data...
}
}
public class FooModelImplementation2 : IFooModel
{
public FooModelImplementation2()
{ }
public FooData GetData(int dataID)
{
// Get data from source 2...
}
}
And my Controller
:
// FooController.cs
public FooController : BaseController
{
private IFooModel mFooModel;
public FooController(IFooModel fooModel)
{
mFooModel = fooModel;
}
// http://www.example.com/Foo?dataID=1&location=2
public ViewResult FooView(int dataID)
{
// Here I want the mFooModel to be an instance of FooModelImplementation2
// because "location" is 2. How do I do this?
FooData data = mFooModel.GetData(dataID);
FooViewModel viewModel = new FooViewModel
{
Field1 = data.Field1;
Field2 = data.Field2;
};
return View(viewModel);
}
}
public class FooViewModel
{
public string Field1 {get; set;}
public string Field2 {get; set;}
public FooViewModel()
{ }
}
Upvotes: 2
Views: 1054
Reputation: 32725
Use the factory extension (https://github.com/ninject/Ninject.Extensions.Factory/wiki/Factory-interface%3A-Referencing-Named-Bindings) to inject a factory into the controller instead of the model.
The factory can be used to get named instances. Create two named bindings and choose the appropriate one in the controller.
Upvotes: 1