I think it is in there but it s pretty buried. Usually I use the following extension:

using System.Collections.Generic;
using System.Collections.ObjectModel;
using Microsoft.Practices.Unity;

namespace NBody.Viewer.Unity

{
    public class QueryableContainerExtension : UnityContainerExtension
    {
        private List<RegisterEventArgs> _registrations;
        public IList<RegisterEventArgs> Registrations
        {
            get { return new ReadOnlyCollection<RegisterEventArgs>(_registrations); }
        }

        private List<RegisterInstanceEventArgs> _instanceRegistrations;
        public IList<RegisterInstanceEventArgs> InstanceRegistrations
        {
            get { return new ReadOnlyCollection<RegisterInstanceEventArgs>(_instanceRegistrations); }
        }

        protected override void Initialize()
        {
            _registrations = new List<RegisterEventArgs>();
            _instanceRegistrations = new List<RegisterInstanceEventArgs>();
            Context.Registering += (s, e) => _registrations.Add(e);
            Context.RegisteringInstance += (s, e) => _instanceRegistrations.Add(e);
        }

        public bool IsTypeRegistered<TFrom, TTo>()
        {
            return _registrations.Exists(e => e.TypeFrom == typeof(TFrom) && e.TypeTo == typeof(TTo));
        }

        public bool IsTypeRegistered<TFrom>()
        {
            return _registrations.Exists(e => e.TypeFrom == typeof(TFrom));
        }
    }
}

Then you can write code like this:

    [Fact]
    public void IsTypeRegisteredReturnsTrueForRegisteredType()
    {
        QueryableContainerExtension target = new QueryableContainerExtension();
        IUnityContainer container = new UnityContainer();
        container.AddExtension(target);

        container.RegisterType<IEnumerable, Array>();

        Assert.True(target.IsTypeRegistered<IEnumerable, Array>());
        Assert.True(target.IsTypeRegistered<IEnumerable>());
        Assert.False(target.IsTypeRegistered<IEnumerable, SortedList>());
        Assert.False(target.IsTypeRegistered<IList>());
    }

You could use this approach or you could wrap or alter the source for the container to add a DebuggerDisplay attribute and a method which uses the above code to iterate through the container contents.

Hope this helps!

You don t need to register an extension for that. In the debugger view of the container simply expand "Registrations" There expand the "Results View" marked by the circle with the two arrows. This will enumerate the registrations and you can expand them.