Owin与mvc

学习链接

http://www.cnblogs.com/JustRun1983/p/3967757.html

第一部分：

直接表达式方法

[assembly: OwinStartup(typeof(OwinTest.Startup))]
namespace OwinTest
{
    public class Startup
    {
        public void Configuration(IAppBuilder app)
        {

            app.Run(context =>
            {
                //context.Environment
                context.Response.ContentType = "text/plain";
                return context.Response.WriteAsync("Hello world");
            });
        }
    }
}

invoke方法

[assembly: OwinStartup(typeof(OwinWebForm.Startup))]
namespace OwinWebForm
{
    public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.Run(Invoke);
        }
        public Task Invoke(IOwinContext context)
        {
            context.Response.ContentType = "text/plain";
            return context.Response.WriteAsync("hello world");
        }

    }
    public class OwinApp2
    {

        public static Task Invoke(IOwinContext context)
        {
            context.Response.ContentType = "text/plain";
            return context.Response.WriteAsync("Hello World special");
        }
    }
}

使用自定义Middleware

public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.Use<CacheMiddleware>();
            app.Use<HelloMiddleware>();

        }

    }

  public class HelloMiddleware : OwinMiddleware
    {
        public HelloMiddleware(OwinMiddleware next)
            : base(next)
        { }

        public override Task Invoke(IOwinContext context)
        {
            var response = "Hello World ! It is " + DateTime.Now;

            if (context.Environment.ContainsKey("caching.addToCache"))
            {
                var addToCache =context.Environment["caching.addToCache"]  as Action<IOwinContext, string, TimeSpan>;
                addToCache(context, response, TimeSpan.FromSeconds(10));
            }
            context.Response.Write(response);
            //return Task.FromResult(0);
            return Next.Invoke(context);
        }
    }

 public class CacheMiddleware : OwinMiddleware
    {
        public CacheMiddleware(OwinMiddleware next)
            : base(next)
        { }

        private readonly IDictionary<string, CacheItem> _responseCache = new Dictionary<string, CacheItem>();

        public override Task Invoke(IOwinContext context)
        {
            context.Environment["caching.addToCache"] = new Action<IOwinContext, string, TimeSpan>(AddToCache);
            var path = context.Request.Path.Value;

            if (!_responseCache.ContainsKey(path))
            { return Next.Invoke(context); }

            var cacheItem = _responseCache[path];
            if (cacheItem.ExpiryTime <= DateTime.Now)
            { return Next.Invoke(context); }

            context.Response.Write(cacheItem.Response);
            return Task.FromResult(0);
            //return Next.Invoke(context);
        }


        public void AddToCache(IOwinContext context, string response, TimeSpan cacheDuration)
        {
            _responseCache[context.Request.Path.Value] = new CacheItem { Response = response, ExpiryTime = DateTime.Now + cacheDuration };
        }

        private class CacheItem
        {
            public string Response { get; set; }
            public DateTime ExpiryTime { get; set; }
        }

    }

第二部分：

a：在所有程序前调用，直接使用startup。

b：在部分路径下调用，需要在appSetting里设置，把自动开始关闭。

<add key="owin:AutomaticAppStartup" value="false" />

        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();

            WebApiConfig.Register(GlobalConfiguration.Configuration);
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);

            //RouteTable.Routes.MapOwinPath("/", app =>
            //           {
            //               app.Use<CacheMiddleware>();
            //               app.Use<HelloMiddleware>();
            //           });



            //owin 再其它路由配置之前，保证优先级
            //RouteTable.Routes.MapOwinPath("/owin");
            //RouteTable.Routes.MapOwinPath("/special", app =>
            //{
            //    app.Run(OwinApp2.Invoke);
            //});

            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);

        }

或

public class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            //owin 再其它路由配置之前，保证优先级
            RouteTable.Routes.MapOwinPath("/owin");
            RouteTable.Routes.MapOwinPath("/special", app =>
            {
                app.Run(OwinApp2.Invoke);
            });

            routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
            );

        }
    }

注意：using Owin;