How to create a custom IoC Container in c#?

Well, it is pretty simple, as a matter of fact, here is the full source code for the container:

public class DemoContainer
{
    public delegate object Creator(DemoContainer container);

    private readonly Dictionary<string, object> configuration
                   = new Dictionary<string, object>();
    private readonly Dictionary<Type, Creator> typeToCreator
                   = new Dictionary<Type, Creator>();

    public Dictionary<string, object> Configuration
    {
        get { return configuration; }
    }

    public void Register<T>(Creator creator)
    {
        typeToCreator.Add(typeof(T),creator);
    }

    public T Create<T>()
    {
        return (T) typeToCreator[typeof (T)](this);
    }

    public T GetConfiguration<T>(string name)
    {
        return (T) configuration[name];
    }
}

Not really hard to figure out, right? And the client code is as simple:

DemoContainer container = new DemoContainer();
//registering dependecies
container.Register<IRepository>(delegate
{
    return new NHibernateRepository();
});
container.Configuration["email.sender.port"] = 1234;
container.Register<IEmailSender>(delegate
{
    return new SmtpEmailSender(container.GetConfiguration<int>("email.sender.port"));
});
container.Register<LoginController>(delegate
{
    return new LoginController(
        container.Create<IRepository>(),
        container.Create<IEmailSender>());
});

//using the container
Console.WriteLine(
    container.Create<LoginController>().EmailSender.Port
    );