MEF and Workflow Services Integration

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using BaseLibrary;
using System.ComponentModel.Composition.Primitives;
using System.ComponentModel.Composition.Hosting;
using System.IO;

namespace WorkflowServiceLibrary.Mef
{
    public class WorkflowServiceMefProvider : MefWorkflowProvider
    {
        public WorkflowServiceMefProvider(bool useTestServices) : base(useTestServices) { }
        /// <summary>
        /// Register parts to be used when useTestServices is enable in configuration
        /// </summary>
        /// <returns>catalog to be added to MEF</returns>
        protected override ComposablePartCatalog RegisterTestCatalogs()
        {
            // return the catalog, you can use AggregateCatalog, DirectoryCatalog ect here
            return new AssemblyCatalog(string.Concat(Directory.GetParent(AppDomain.CurrentDomain.BaseDirectory).Parent.FullName, "\\TestLibrary\\bin\\debug\\TestLibrary.dll"));
        }
        /// <summary>
        /// Register parts that should always be available to MEF
        /// </summary>
        /// <returns>catalog to be added to MEF</returns>
        protected override ComposablePartCatalog RegisterCoreCatalogs()
        {
            // not used: catalogs registered here will be available regardless of useTestServices
            return null;
        }
        /// <summary>
        /// Register parts to be used when useTestServices is disabled in configuration
        /// </summary>
        /// <returns>catalog to add to MEF</returns>
        protected override ComposablePartCatalog RegisterNormalCatalogs()
        {
            // return the catalog, you can use AggregateCatalog, DirectoryCatalog ect here
            return new AssemblyCatalog(string.Concat(Directory.GetParent(AppDomain.CurrentDomain.BaseDirectory).Parent.FullName, "\\ImplementationLibrary\\bin\\debug\\ImplementationLibrary.dll"));
        }
    }
}