C#/.Net判斷是否為周末/節假日

判斷節假日請求的Api：http://tool.bitefu.net/jiari/

        /// <summary>
        /// 判斷是不是周末/節假日
        /// </summary>
        /// <param name="date">日期</param>
        /// <returns>周末和節假日返回true，工作日返回false</returns>
        public static async Task<bool> IsHolidayByDate(DateTime date)
        {
            var isHoliday = false;
            var webClient = new System.Net.WebClient();
            var PostVars = new System.Collections.Specialized.NameValueCollection
            {
                { "d", date.ToString("yyyyMMdd") }//參數
            };
            try
            {
                var day = date.DayOfWeek;

                //判斷是否為周末
                if (day == DayOfWeek.Sunday || day == DayOfWeek.Saturday)
                    return true;

                //0為工作日，1為周末，2為法定節假日
                var byteResult = await webClient.UploadValuesTaskAsync("http://tool.bitefu.net/jiari/", "POST", PostVars);//請求地址,傳參方式,參數集合
                var result = Encoding.UTF8.GetString(byteResult);//獲取返回值
                if (result == "1" || result == "2")
                    isHoliday = true;
            }
            catch
            {
                isHoliday = false;
            }
            return isHoliday;
        }