protected virtual void LoadMatchingAssemblies(string directoryPath)
        {
            var loadedAssemblyNames = new List <string>();

            foreach (var a in GetAssemblies())
            {
                loadedAssemblyNames.Add(a.FullName);
            }

            if (!_fileProvider.DirectoryExists(directoryPath))
            {
                return;
            }

            foreach (var dllPath in _fileProvider.GetFiles(directoryPath, "*.dll"))
            {
                try
                {
                    var an = AssemblyName.GetAssemblyName(dllPath);
                    if (Matches(an.FullName) && !loadedAssemblyNames.Contains(an.FullName))
                    {
                        App.Load(an);
                    }

                    //old loading stuff
                    //Assembly a = Assembly.ReflectionOnlyLoadFrom(dllPath);
                    //if (Matches(a.FullName) && !loadedAssemblyNames.Contains(a.FullName))
                    //{
                    //    App.Load(a.FullName);
                    //}
                }
                catch (BadImageFormatException ex)
                {
                    Trace.TraceError(ex.ToString());
                }
            }
        }