/// <summary>

    /// 设置api支持namespace

    /// </summary>

    public class NamespaceHttpControllerSelector : DefaultHttpControllerSelector

    {

        private const string NamespaceRouteVariableName = "namespace_name";

        private readonly HttpConfiguration _configuration;

        private readonly Lazy<ConcurrentDictionary<string, Type>> _apiControllerCache;

        public NamespaceHttpControllerSelector(HttpConfiguration configuration)

            : base(configuration)

        {

            _configuration = configuration;

            _apiControllerCache = new Lazy<ConcurrentDictionary<string, Type>>(

                new Func<ConcurrentDictionary<string, Type>>(InitializeApiControllerCache));

        }

        private ConcurrentDictionary<string, Type> InitializeApiControllerCache()

        {

            IAssembliesResolver assembliesResolver = this._configuration.Services.GetAssembliesResolver();

            var types = this._configuration.Services.GetHttpControllerTypeResolver().GetControllerTypes(assembliesResolver).ToDictionary(t => t.FullName, t => t);

            return new ConcurrentDictionary<string, Type>(types);

        }

        public IEnumerable<string> GetControllerFullName(HttpRequestMessage request, string controllerName)

        {

            object namespaceName;

            var data = request.GetRouteData();

            IEnumerable<string> keys = _apiControllerCache.Value.ToDictionary<KeyValuePair<string, Type>, string, Type>(t => t.Key,

                    t => t.Value, StringComparer.CurrentCultureIgnoreCase).Keys.ToList();

            if (!data.Values.TryGetValue(NamespaceRouteVariableName, out namespaceName))

            {

                return from k in keys

                       where k.EndsWith(string.Format(".{0}{1}", controllerName,

                       DefaultHttpControllerSelector.ControllerSuffix), StringComparison.CurrentCultureIgnoreCase)

                       select k;

            }

            string[] namespaces = (string[])namespaceName;

            return from n in namespaces

                   join k in keys on string.Format("{0}.{1}{2}", n, controllerName,

                   DefaultHttpControllerSelector.ControllerSuffix).ToLower() equals k.ToLower()

                   select k;

        }

        public override HttpControllerDescriptor SelectController(HttpRequestMessage request)

        {

            Type type;

            if (request == null)

            {

                throw new ArgumentNullException("request");

            }

            string controllerName = this.GetControllerName(request);

            if (string.IsNullOrEmpty(controllerName))

            {

                throw new HttpResponseException(request.CreateErrorResponse(HttpStatusCode.NotFound,

                    string.Format("No route providing a controller name was found to match request URI '{0}'", new object[] { request.RequestUri })));

            }

            IEnumerable<string> fullNames = GetControllerFullName(request, controllerName);

            if (fullNames.Count() == 0)

            {

                throw new HttpResponseException(request.CreateErrorResponse(HttpStatusCode.NotFound, string.Format("No route providing a controller name was found to match request URI '{0}'", new object[] { request.RequestUri })));

            }

            if (this._apiControllerCache.Value.TryGetValue(fullNames.First(), out type))

            {

                return new HttpControllerDescriptor(_configuration, controllerName, type);

            }

            throw new HttpResponseException(request.CreateErrorResponse(HttpStatusCode.NotFound, string.Format("No route providing a controller name was found to match request URI '{0}'", new object[] { request.RequestUri })));

        }

    }

    public static class WebApiConfig

    {

        public static void Register(HttpConfiguration config)

        {

            //注册支持namespace的HttpControllerSelector，替换默认DefaultHttpControllerSelector

            config.Services.Replace(typeof(IHttpControllerSelector), new NamespaceHttpControllerSelector(GlobalConfiguration.Configuration));

            config.Routes.MapHttpRoute(

                name: "Phone",

                routeTemplate: "api/phone/{controller}/{action}/{id}",

                defaults: new

                {

                    id = RouteParameter.Optional,

                    namespace_name = new string[] { "Amy.WebUI.Api.Phone" }

                }

            );

            config.Routes.MapHttpRoute(

                name: "ApiDefault",

                routeTemplate: "api/{controller}/{action}/{id}",

                defaults: new

                {

                    id = RouteParameter.Optional,

                    namespace_name = new string[] { "Amy.WebUI.Api" }

                }

            );

        }

    }