DI Conditional Registration

gistfile1.cs

public interface IBusinessLogicService
{
	int DoSomething(int x);
}

public class MainLogicService : IBusinessLogicService
{
	public int DoSomething(int x)
	{
		return 1 + x;
	}
}

public class AltLogicService : IBusinessLogicService
{
	public int DoSomething(int x)
	{
		return 1 - x;
	}
}

public class Doer
{
	private readonly IBusinessLogicService _logicService;

	public Doer(IBusinessLogicService logicService)
	{
		_logicService = logicService;
	}

	public int DoIt(int x)
	{
		return _logicService.DoSomething(x);
	}
}

public class Context
{
	private const int Config = 1;
	public void Main()
	{
		var container = new UnityContainer();
		if (Config == 1)
			container.RegisterType<IBusinessLogicService, MainLogicService>();
		else
			container.RegisterType<IBusinessLogicService, AltLogicService>();

		var doer = container.Resolve<Doer>();
		var result = doer.DoIt(2);
		Console.WriteLine(result);

	}
}