How to get query string parameter from MVC Razor markup?

Question

I want to check the URL parameter in my Razor markup. For example, how do I do something like this:

Answer 1

I think a more elegant solution is to use the controller and the ViewData dictionary:

//Controller:
public ActionResult Action(int IFRAME)
    {
        ViewData["IsIframe"] = IFRAME == 1;
        return View();
    }

//view
@{
    string classToUse = (bool)ViewData["IsIframe"] ? "iframe-page" : "";
   

 }