netcore/asp-netcore-session-sample/Pages/Index.cshtml.cs

using System;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using SessionSample.Middleware;
using Web.Extensions;

namespace SessionSample.Pages {
  public class IndexModel : PageModel {
    public const string SessionKeyName = "_Name";
    public const string SessionKeyAge = "_Age";
    const string SessionKeyTime = "_Time";

    public string SessionInfo_Name { get; private set; }
    public string SessionInfo_Age { get; private set; }
    public string SessionInfo_CurrentTime { get; private set; }
    public string SessionInfo_SessionTime { get; private set; }
    public string SessionInfo_MiddlewareValue { get; private set; }

    public void OnGet() {
      // Requires: using Microsoft.AspNetCore.Http;
      if (string.IsNullOrEmpty(HttpContext.Session.GetString(SessionKeyName))) {
        HttpContext.Session.SetString(SessionKeyName, "The Doctor");
        HttpContext.Session.SetInt32(SessionKeyAge, 35);
      }

      var name = HttpContext.Session.GetString(SessionKeyName);
      var age = HttpContext.Session.GetInt32(SessionKeyAge);
      SessionInfo_Name = name;
      SessionInfo_Age = age.ToString();

      var currentTime = DateTime.Now;

      // Requires SessionExtensions from sample download.
      if (HttpContext.Session.Get<DateTime>(SessionKeyTime) == default) {
        HttpContext.Session.Set<DateTime>(SessionKeyTime, currentTime);
      }

      SessionInfo_CurrentTime = currentTime.ToString("H:mm:ss tt");
      SessionInfo_SessionTime =
          HttpContext.Session.Get<DateTime>(SessionKeyTime).ToString("H:mm:ss tt");

      HttpContext.Items.TryGetValue(HttpContextItemsMiddleware.HttpContextItemsMiddlewareKey,
                                    out var middlewareSetValue);
      SessionInfo_MiddlewareValue = middlewareSetValue?.ToString() ?? "Middleware value not set!";
    }

    public IActionResult OnPostUpdateSessionDate() {
      HttpContext.Session.Set<DateTime>(SessionKeyTime, DateTime.Now);

      return RedirectToPage();
    }

    public IActionResult OnPostChangeAge() {
      var r = new Random();

      HttpContext.Session.SetInt32(SessionKeyAge, r.Next(35, 65));

      return RedirectToPage();
    }
  }
}