Delete cookie during redirect

If a request comes in with a certain cookie set, I want to delete that cookie, and redirect back to the same action (and preserve querystring, route values, etc.)

I expect that in the second (redirected) request, the cookie will be gone. But it isn't.

My action method:

[DeleteCookie]
public virtual ActionResult doStuff() {
  // blah
}

My action filter:

[AttributeUsage(AttributeTargets.Method, AllowMultiple = false)]
public class DeleteCookieAttribute : ActionFilterAttribute {

  public override void OnActionExecuting(ActionExecutingContext context) {

    var request = context.HttpContext.Request;

    if (request.Cookies.AllKeys.Contains("foo")) {
      request.Cookies["foo"].Expires = DateTime.Now.AddYears(-1);     // I tried this
      request.Cookies.Remove("foo");                                  // I tried this
      context.Result = new RedirectToRouteResult(context.RouteData.Values);
    }

  base.OnActionExecuting(_filterContext);
  }

}

During the first request, once I delete the cookie, it disappears from the request. But in the second redirected request, it's still there! And so the code above goes into an infinite loop.

How do I remove it?

Try this:

HttpCookie cookie = Request.Cookies["foo"];
if (cookie != null)
{
    cookie .Expires = DateTime.Now.AddYears(-1);
    Response.Cookies.Add(cookie);
}