删除kookie

注意不同域名的需要加上domain属性

HttpCookie cookie1 = HttpContext.Current.Request.Cookies["cookie1"];
                            if(cookie1 != null)
                            {
                                cookie1.Expires = DateTime.Now.AddDays(-1);
                                cookie1.Domain = ".test.com";
                                HttpContext.Current.Response.Cookies.Add(cookie1);
                            }