요일 구하기

DateTime dt = DateTime.Now;       
                    var d = dt.DayOfWeek;
                        string ret = string.Empty;
                        switch (d)
                        {
                        case DayOfWeek.Friday:
                        ret = "금";
                        break;
                        case DayOfWeek.Monday:
                        ret = "월";
                        break;
                        case DayOfWeek.Saturday:
                        ret = "토";
                        break;
                        case DayOfWeek.Sunday:
                        ret = "일";
                        break;
                        case DayOfWeek.Thursday:
                        ret = "목";
                        break;
                        case DayOfWeek.Tuesday:
                        ret = "화";
                        break;
                        case DayOfWeek.Wednesday:
                        ret = "수";
                        break;
                        default:
                        break;
                        }
                        if ((ret == "금" && DateTime.Now.Hour >= 18) || ret == "토" || ret == "일")
                {
                    Response.Write("<script>alert('해당 기간이 아닙니다.');location.href='url';</script>");
                    return;
                }