C#

//--This is an external assembly project (.dll)
namespace Foo
{
    [Serializable]
    public class Foo
    {
        Thread workThread_;

        public void Initialize()
        {
            workThread_ = new Thread(new ThreadStart(DoWork));
            workThread_.Start();
        }

        public void DoWork()
        {
            int i = 0;

            while (i < 500)
                i++;

            throw new Exception("Unhandled exception");
        }
    }
}

namespace AppDomainTest
{
    public class Bar
    {

        AppDomain new_domain;

        public Bar()
        {
           
        }

        private void new_domain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
        {
           //--Cleanup new_domain and dispose it
            new_domain = null;
	    
	    //--After this event handler finishes so the main application process finishes although the event handler is subsrcibed on foo_test
        }

        public void InitializeBar()
        {
            Foo.Foo foo_test;

            new_domain = AppDomain.CreateDomain("Auxilary domain");
            foo_test = (Foo.Foo)new_domain.CreateInstanceFromAndUnwrap("Foo.dll", "Foo.Foo");
            
            new_domain.UnhandledException += new UnhandledExceptionEventHandler(new_domain_UnhandledException);

            foo_test.Initialize();
        }
    }
}