I want to check first the session as this action

Yes, you can enforce this check for all actions in your MVC application without manually adding the session check to each action by using a custom action filter. Action filters are attributes that can be applied globally to controllers or actions, allowing you to perform common tasks like session checks in a centralized manner.

Create a new class for your custom action filter attribute. Let's call it SessionCheckAttribute.

using System;
using System.Web.Mvc;

public class SessionCheckAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        var session = filterContext.HttpContext.Session;
        if (session["UserInfo"] == null)
        {
            filterContext.Result = new RedirectResult("~/Home/Login");
        }
        
        base.OnActionExecuting(filterContext);
    }
}

Apply the custom attribute to your controller or actions where you want the session check to be enforced:

[SessionCheck] // Apply the custom attribute at the controller level
public class HomeController : Controller
{
    public ActionResult Index()
    {
        return View();
    }

    public ActionResult AnotherAction()
    {
        return View();
    }
}

//OR

public class HomeController : Controller
{
    [SessionCheck] // Apply the custom attribute at the action level
    public ActionResult Index()
    {
        return View();
    }

    public ActionResult AnotherAction()
    {
        return View();
    }
}