asp.net mvc global variables without cookies and session[""] - asp.net

Question

Is there any method for storing global variables without using cookies or session[""] in asp.net mvc ?
I know that cookies and session[""] have some disadvantages and I want to use the best method if exit.

Answer 1

If they are indeed global variables, you should implement the singleton pattern and have an Instance globally accessible that holds your variables.
Here is a simple example:
public sealed class Settings
{
private static Settings instance = null;
static readonly object padlock = new object();
// initialize your variables here. You can read from database for example
Settings()
{
this.prop1 = "prop1";
this.prop2 = "prop2";
}
public static Settings Instance
{
get
{
lock (padlock)
{
if (instance == null)
{
instance = new Settings();
}
return instance;
}
}
}
// declare your global variables here
public string prop1 { get; set; }
public string prop2 { get; set; }
}
The you can use them in your code like this:
var globalvar1 = Settings.Instance.prop1;
This class with its variables will be initialized only once (when the application starts) and it will be available in your application globally.

Answer 2

Basically you have following options:
Cookies - valid as long as you set, must be allowed by client's browser, can be deleted by user, stored on user's PC.
Session - valid for all requests, not for a single redirect, stored on server.
ViewData - after redirect it's cleared (lives only during single request).
TempData - it's useful for passing short messages to view, after reading a value it's deleted.
ViewBag - is available only during the current request, if redirection occurs then it’s value becomes null, is dynamic so you don't have intellisense and errors may occur only in runtime.
Here - http://www.dotnet-tricks.com/Tutorial/mvc/9KHW190712-ViewData-vs-ViewBag-vs-TempData-vs-Session.html - you can find fantastic article which describes them.

Answer 3

Sure: HttpContextBase.Application (no expiration) or HttpContextBase.Cache (with expiration). You can access the HttpContextBase instance through the HttpContext property of the Controller class.

Answer 4

So... HACK ALERT... There is no good way to do an MVC 5 or 6 web app using session variables that I have found (yet). MVC doesn't support Session variables or Cookies, which are implemented via session variables. Global variables will be set for ALL users, which is not how Session variables work.
However, you can store "session variables" based on the User.Identity.Name or the underlying User.Identity.Claims.AspNet.Identity.SecurityStamp into a database along with a timestamp and viola! You have implemented primitive session variables. I had a very specific need to save two weeks of programming by not interfering with the GUI that our user interface specialist had written. So I returned NoContent() instead of the normal View() and I saved my hacky session variable based on the user's login name.
Am I recommending this for most situations? No. You can use ViewBag or return View(model) and it will work just fine. But if you need to save session variables in MVC for whatever reason, this code works. The code below is in production and works.
To retrieve the data...
string GUID = merchdata.GetGUIDbyIdentityName(User.Identity.Name);
internal string GetGUIDbyIdentityName(string name)
{
string retval = string.Empty;
try
{
using (var con = new SqlConnection(Common.DB_CONNECTION_STRING_BOARDING))
{
con.Open();
using (var command = new SqlCommand("select GUID from SessionVariablesByIdentityName md where md.IdentityName = '" + name + "' and LastSaved > getdate() - 1", con))
{
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
retval = reader["GUID"].ToString();
}
}
}
}
}
catch (Exception ex)
{
}
return retval;
}
To save the data...
merchdata.SetGUIDbyIdentityName(User.Identity.Name, returnedGUID);
internal void SetGUIDbyIdentityName(string name, string returnedGUID)
{
RunSQL("exec CRUDSessionVariablesByIdentityName #GUID='" + returnedGUID + "', #IdentityName = '" + name + "'");
}
internal void RunParameterizedSQL(SqlConnection cn, SqlCommand cmd, object sqlStr)
{
string retval = string.Empty;
try
{
cn.Open();
cmd.ExecuteNonQuery();
cn.Close();
}
BTW: The SQL table (named SessionVariablesByIdentityName here) is fairly straightforward and can store lots of other things too. I have a LastSaved datetime field in there so I don't bother retrieving old data from yesterday. For example.