A function with this signature can be used for the
AddValidationCallback( ) method of the
HttpCachePolicy class. Using this method gives you
the opportunity to check other dependencies that a cached page may
have and either allow the page to be served or invalidate it and
require the page to be recompiled. To invalidate a page, set the
validationStatus parameter to
HttpValidationStatus.Invalid.
public delegate void HttpCacheValidateHandler(HttpContext context, object data,
ref HttpValidationStatus validationStatus);