How to initialize and use Custom / Support classes in MVC 6 with Asp.Net Core 2.0 - class

Question

public sealed class SessionContext
{
private ISession httpContext;
public SessionContext(ISession httpContext)
{
this.httpContext = httpContext;
}
public string UserType
{
get
{
return httpContext.GetString("_UserType");
}
set
{
httpContext.SetString("_UserType", value);
}
}
...... More properties .....
}
public class HomeController : Controller
{
private AppSettings _appSettings;
private SessionContext session = null;
private readonly IHttpContextAccessor _httpContextAccessor;
private ISession httpContext => _httpContextAccessor.HttpContext.Session;
//I don't like this constructor as it is getting initialize or every controller call.
public HomeController(IOptions<AppSettings> myAppSettings, IHttpContextAccessor httpContextAccessor)
{
_appSettings = myAppSettings.Value;
_httpContextAccessor = httpContextAccessor;
appSettings = new AppSettings(_appSettings); //Should initialize only once.
session = new SessionContext(httpContext);
}
}
I have questions regarding ...
How to initialize and use Custom / Support classes in MVC 6 with Asp.Net Core 2.0
When I Initialize these classes, they getting initialize or every controller call. That is very redundant.
my SessionContext class is getting re-initialize every time. So I am loosing the values when I call this class from another controller.
I tried this approach but, not much of use.
services.AddSingleton();

Answer 1

Move from question to answer:
public void ConfigureServices(IServiceCollection services)
{
services.AddOptions();
services.AddSingleton<SessionContext, SessionContext>();
//calling the extension class to instantiate the classes which we require earlier.
services.AddMyProjectHelper(Configuration)
}
Created a extension class... where it initializes the support classes
public static class MyProjectHelperExtensions
{
public static IServiceCollection AddMyProjectHelper(this IServiceCollection services, IConfiguration configuration)
{
var section = configuration.GetSection("AppSettings");
// we first need to create an instance
var settings = new AppSettings();
// then we set the properties
new ConfigureFromConfigurationOptions<AppSettings>(section).Configure(settings);
var session = services.BuildServiceProvider().GetService<SessionContext>();
// then we register the instance into the services collection
services.AddSingleton<MyProjectHelper>(new MyProjectHelper(settings, session));
return services;
}
}
finally controller ctor uses the DI for the required class. Now I have avoided redundant initialization of support classes.
public SecurityController(MyProjectHelper objHelper, SessionContext sessionContext)
{
session = sessionContext;
projectHelper = projectHelper ?? objHelper;
}
Now, I am able to share the session variables which I have set in my support classes
private SessionContext session = null;
public HomeController(SessionContext sessionContext)
{
session = sessionContext;
}
[Authorize]
public IActionResult Index()
{
if (session.CurrEmployee != null)
{
ViewBag.Name = (session.CurrEmployee.FirstName + " " + session.CurrEmployee.LastName);
return View();
}
}