web api control注册及重写DefaultHttpControllerSelector、ApiControllerActionSelector、ApiControllerActionInvoker（转）

出处：http://www.cnblogs.com/kingCpp/p/4651154.html

namespace EWorkpal.WebApi
{
    public class HttpNotFoundDefaultHttpControllerSelector : DefaultHttpControllerSelector
    {
        public HttpNotFoundDefaultHttpControllerSelector(HttpConfiguration configuration)
            : base(configuration)
        {
        }
        public override HttpControllerDescriptor SelectController(HttpRequestMessage request)
        {
            HttpControllerDescriptor decriptor = null;
            try
            {
                decriptor = base.SelectController(request);
            }
            catch (HttpResponseException ex)
            {
                var code = ex.Response.StatusCode;
                var result = new EWorkResultInfo<object> { Code = 10006, Entity = ex.Response.Content.ReadAsAsync<object>().Result };
                if (code == HttpStatusCode.NotFound || code == HttpStatusCode.MethodNotAllowed)
                {
                    ex.Response.Content = new ObjectContent(typeof(EWorkResultInfo), result, GlobalConfiguration.Configuration.Formatters.JsonFormatter);
                }
                throw;
            }
            return decriptor;
        }


    }

    public class HttpNotFoundControllerActionSelector : ApiControllerActionSelector
    {
        public override HttpActionDescriptor SelectAction(HttpControllerContext controllerContext)
        {
            HttpActionDescriptor decriptor = null;
            try
            {
                decriptor = base.SelectAction(controllerContext);
            }
            catch (HttpResponseException ex)
            {
                var code = ex.Response.StatusCode;
                var result = new EWorkResultInfo<object> { Code = 10006, Entity = ex.Response.Content.ReadAsAsync<object>().Result };
                if (code == HttpStatusCode.NotFound || code == HttpStatusCode.MethodNotAllowed)
                {
                    ex.Response.Content = new ObjectContent(typeof(EWorkResultInfo), result, GlobalConfiguration.Configuration.Formatters.JsonFormatter);
                }
                throw;
            }
            return decriptor;
        }
    }

    public class CustomApiControllerActionInvoker : ApiControllerActionInvoker
    {
        public override Task<HttpResponseMessage> InvokeActionAsync(HttpActionContext actionContext, CancellationToken cancellationToken)
        {
            var responseMessage = base.InvokeActionAsync(actionContext, cancellationToken);

            if (responseMessage.Exception != null)
            {
                var baseException = responseMessage.Exception.InnerExceptions[0];

                var result = new EWorkResultInfo<object>
                {
                    Message = baseException.Message, //"服务器内部错误",
                    Code = 10001,
                    Entity = responseMessage.Exception
                };

                if (baseException is TimeoutException)
                {
                    result.Code = 10004;
                    //result.Message = "任务超时";
                }

                return Task.Run(() => new HttpResponseMessage()
                {
                    Content = new ObjectContent(typeof(EWorkResultInfo<object>), result, GlobalConfiguration.Configuration.Formatters.JsonFormatter)
                }, cancellationToken);
            }
            return responseMessage;
        }
    } 
}

webapi.config

public static class WebApiConfig
    {
        /// <summary>
        /// 
        /// </summary>
        /// <param name="config"></param>
        public static void Register(HttpConfiguration config)
        {
            // Web API configuration and services
            config.Filters.Add(new EWorkAuthorize());
            config.Filters.Add(new ModelValidationFilterAttribute());
            config.Services.Replace(typeof(IHttpActionInvoker), new CustomApiControllerActionInvoker());  
            config.Services.Replace(typeof(IHttpControllerSelector), new HttpNotFoundDefaultHttpControllerSelector(config));
            config.Services.Replace(typeof(IHttpActionSelector), new HttpNotFoundControllerActionSelector());

            // Web API routes
            config.MapHttpAttributeRoutes();

            config.Routes.MapHttpRoute(
                name: "DefaultApi",
                routeTemplate: "api/{controller}/{action}"//,//{id}
                //defaults: new { id = RouteParameter.Optional }
            );

            var xmlFormatter = config.Formatters.FirstOrDefault(m => m is XmlMediaTypeFormatter);
            config.Formatters.Remove(xmlFormatter);

            config.Formatters.JsonFormatter.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
            //config.Formatters.JsonFormatter.SerializerSettings.NullValueHandling = NullValueHandling.Ignore;
            config.Formatters.JsonFormatter.SerializerSettings.DateFormatString = "yyyy-MM-dd hh:mm";
            
        }
    }

global注册

GlobalConfiguration.Configure(WebApiConfig.Register);