ASP.NET MVC5控制器和Autofac

Question

I implemented a design as described here , with ASP.NET MVC5, repository pattern, UoW and Autofac.

Everything works for controllers with a single service, but I have a controller that requires three services:

public MyController(IService1 service1, IService2 service2, IService3 service3)
{
    _service1= service1;
    _service2= service2;
    _service3= service3;
}

Now, I register the services like this:

protected override void Load(ContainerBuilder builder)
{
    builder.RegisterAssemblyTypes(Assembly.Load("namespace.service"))
              .Where(t => t.Name.EndsWith("Service"))
              .AsImplementedInterfaces()
              .InstancePerLifetimeScope();
}

At runtime, I get this error:

None of the constructors found with 'Autofac.Core.Activators.Reflection.DefaultConstructorFinder' on type 'namespace.Controllers.MyController' can be Invoked with the available services and parameters: Can not resolve parameter '.service.Service1 service1 constructor of 'Void .ctor ...

Answer 1

It doesn't really matter how many constructor parameters your controller has. If Autofac reports that it cannot resolve service1 , it means that IService1 is not registered.

There might be an issue with registering assembly types due to wrong query or assembly. To verify this, try commenting out the RegisterAssemblyTypes and use RegisterType<Service1>().As<IService1>().InstancePerRequest() for all three services and see if it helps. Also check if your module Load actually gets called.

If registering services explicitly worked, you can try getting back to RegisterAssemblyTypes but use service assembly from the service type instead of loading it by name:

    builder.RegisterAssemblyTypes(typeof (Service1).Assembly)
        .Where(t => t.Name.EndsWith("Service"))
        .AsImplementedInterfaces()
        .InstancePerRequest();