MEF load plugin from directory

var catalog = new AggregateCatalog();
catalog.Catalogs.Add(new DirectoryCatalog("."));
var container = new CompositionContainer(catalog);

var catalog = new AggregateCatalog();
catalog.Catalogs.Add(new AssemblyCatalog(Assembly.GetExecutingAssembly()));
catalog.Catalogs.Add(new DirectoryCatalog("."));
var container = new CompositionContainer(catalog);

public void AssembleCalculatorComponents()
        {

            string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Plugins");
            Console.WriteLine(path);
            //Check the directory exists
            if (!Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }
            Console.WriteLine(path);
            string assemblyName = Assembly.GetEntryAssembly().FullName;
            Console.WriteLine(assemblyName);
            //Create an assembly catalog of the assemblies with exports
            var catalog = new AggregateCatalog(
                new AssemblyCatalog(Assembly.GetExecutingAssembly().Location),
                new AssemblyCatalog(Assembly.Load(assemblyName)),
                new DirectoryCatalog(path, "*.dll"));

            //Create a composition container
            var container = new CompositionContainer(catalog);
            container.ComposeParts(this);