C# 跨域清除写入Cookie

/清除写入cookie        public void deleteCookie()        {            HttpCookie acookie = HttpContext.Current.Request.Cookies["Username"];            if (acookie != null)            {                acookie.Expires = DateTime.Now.AddDays(-20);                acookie.Domain = ".zgbfw.com";                HttpContext.Current.Response.AppendCookie(acookie);            }            HttpCookie acookie1 = HttpContext.Current.Request.Cookies["Userpass"];            if (acookie1 != null)            {                acookie1.Expires = DateTime.Now.AddDays(-20);                acookie1.Domain = ".zgbfw.com";                HttpContext.Current.Response.AppendCookie(acookie1);            }        }