How to pass through the AntiForgeryToken to another action? The following does of course not work:
[ValidateAntiForgeryToken]
public ActionResult CheckSelection(
That is not possible. The anti-forgery token is based on both an Http Cookie and a hidden value in your Form; when doing an Action Redirect, that form value is lost and therefore the anti-forgery token cannot be validated.
You will need to come up with a design that does not need action redirect...