非.aspx/.aspx.cs 中引用Response,Request等使用類請使用，
HttpResponse resp = System.Web.HttpContext.Current.Response;
HttpRequest req = System.Web.HttpContext.Current.Request;
HttpServerUtility server = System.Web.HttpContext.Current.Server;
HttpSessionState session = System.Web.HttpContext.Current.Session;
// ....
所有這些使用類實例都作爲Page中對應的實例屬性公開
