How to access session variables in Web API Controller in ASP.Net MVC

Step 1:- Create SessionHttpControllerHandler class under Global.asax.cs

using System.Web.Http.WebHost;

using System.Web.SessionState;

    public class SessionHttpControllerHandler   : HttpControllerHandler, IRequiresSessionState

    {

        public SessionHttpControllerHandler(RouteData routeData)

            : base(routeData)

        {

        }

    }

Step 2:- Create SessionHttpControllerRouteHandler class under  Global.asax.cs

public class SessionHttpControllerRouteHandler : HttpControllerRouteHandler

    {

        protected override IHttpHandler GetHttpHandler(RequestContext requestContext)

        {

            return new SessionHttpControllerHandler(requestContext.RouteData);

        }

    }

Step 3:- Create SessionHttpControllerRouteHandler class under  Global.asax.cs

public class SessionHttpControllerRouteHandler : HttpControllerRouteHandler

    {

        protected override IHttpHandler GetHttpHandler(RequestContext requestContext)

        {

            return new SessionHttpControllerHandler(requestContext.RouteData);

        }

    }

Step 4:- Open WebApiConfig.cs under App_Start folder and Comment following Code

 public static void Register(HttpConfiguration config)

        {

            //config.Routes.MapHttpRoute(

            //    name: "DefaultApi",

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

            //    defaults: new { id = RouteParameter.Optional }

            //);

        }

Step 5:- Open RouteConfig.cs under App_Start folder and Copy Past highlighted code

public static void RegisterRoutes(RouteCollection routes)

        {

            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

            routes.MapHttpRoute(

               name: "DefaultApi",

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

               defaults: new { id = RouteParameter.Optional }

               ).RouteHandler = new SessionHttpControllerRouteHandler(); 

            routes.MapRoute(

                name: "Default",

                url: "{controller}/{action}/{id}",

                defaults: new { controller = "Question", action = "Index", id = UrlParameter.Optional }

            );

        }

Step 6:- Api Controller

 public class TestController : ApiController

    {

        public string Get()

        {

            var session = System.Web.HttpContext.Current.Session;

            if (session != null)

            {

                // Add Your Code here

            }

            return "No Session Exists";

        }

    }

Note:-

It's not compulsory to create a class in Global.asax.cs file. You can also add in model.