Ninject, multiple service bindings

Question

I am using Ninject to load several modules. When two modules try to bind two different implementations for an interface, ninject raises an error that multiple binding for a service are not allowed.

All other IoC frameworks I'm using (Unity, Windsor, Spring.net, etc) all have the ability to 'register' multiple implementations for an interface.

Let me give a real life example:

public class HealtMonitorEmailAlertServiceModule : StandardModule
{
    public override void Load()
    {
        this.Bind<IAlertService>().To<EmailAlertService>();
    }
}

public class HealtMonitorSmsAlertServiceModule : StandardModule
{
    public override void Load()
    {
        this.Bind<IAlertService>().To<SmsAlertService>();
    }
}

public class Program
{
    static void Main()
    {
        var emailService = new HealtMonitorEmailAlertServiceModule();
        var smsService = new HealtMonitorSmsAlertServiceModule();

        IKernel kernel = new StandardKernel(emailService, smsService);  
        kernel.Get<IAlertService>()
    }
}

The above generates an exception, i would expect it to resolve the type registered in the last module to load into the kernel. I have tried the exact same approach using Autofac and it works as I expected.

Answer 1

Ninject 2.0 has this capability, but Ninject 1.x does not. While 2.0 is still in beta, I'd encourage you to take a look, because 1.x will be end-of-life within a couple of months.