Session variable value is getting null in ASP.NET Core

Question

I am setting a session variable in one method and trying to get the session variable value from the another method in a controller but its always getting null:

Here is my code:

public class HomeController : Controller {     public IActionResult Index()     {          HttpContext.Session.SetString("Test", "Hello!");         var message = HttpContext.Session.GetString("Test");// Here value is getting correctly         return View();     }      public IActionResult About()     {         var message = HttpContext.Session.GetString("Test"); // This value is always getting null here          return View();     } } 

Here is my session configuration in Startup class:

In ConfigureServices() method:

services.Configure<CookiePolicyOptions>(options => {     // This lambda determines whether user consent for non-essential cookies is needed for a given request.     options.CheckConsentNeeded = context => true;     options.MinimumSameSitePolicy = SameSiteMode.None; });  services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1); services.AddDistributedMemoryCache(); services.AddMvc().AddSessionStateTempDataProvider(); services.AddSession(options => {     options.Cookie.Name = "TanvirArjel.Session";     options.IdleTimeout = TimeSpan.FromDays(1); }); 

In Configure() method:

app.UseSession(); app.UseMvc(routes => {     routes.MapRoute(         name: "default",         template: "{controller=Home}/{action=Index}/{id?}"); }); 

Very strange and peculiar problem! Any help will be highly appreciated!

Answer 1

For ASP.NET Core 2.1 and 2.2

In the ConfigureServices method of the Startup class, Set options.CheckConsentNeeded = context => false; as follows:

services.Configure<CookiePolicyOptions>(options => {   // This lambda determines whether user consent for non-essential cookies is needed for a given request.   options.CheckConsentNeeded = context => false;   options.MinimumSameSitePolicy = SameSiteMode.None; }); 

Problem solved!