ASP.NET MVC: The right way to propagate query parameter through all ActionLinks

Question

In my application, key query string parameter can be used to grant access to certain actions/views.
Now I want all ActionLinks and Forms to automatically in

Answer 1

The simplest thing is to put the "key" parameter in all the Url.Action and Html.ActionLink in this way:

@Url.Action("MyAction", "MyController", new { key = Request["key"] })

if Request["key"] is empty the querystring parameter will be skipped.