C#/.Net判断是否为周末/节假日

判断节假日请求的Api：http://tool.bitefu.net/jiari/

         /// <summary>
         /// 判断是不是周末/节假日
         /// </summary>
         /// <param name="date">日期</param>
         /// <returns>周末和节假日返回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") }//参数
             };
             try
             {
                 var day = date.DayOfWeek;

                 //判断是否为周末
                 if (day == DayOfWeek.Sunday || day == DayOfWeek.Saturday)
                     return true;

                 //0为工作日，1为周末，2为法定节假日
                 var byteResult = await webClient.UploadValuesTaskAsync("http://tool.bitefu.net/jiari/", "POST", PostVars);//请求地址,传参方式,参数集合
                 var result = Encoding.UTF8.GetString(byteResult);//获取返回值
                 if (result == "" || result == "")
                     isHoliday = true;
             }
             catch
             {
                 isHoliday = false;
             }
             return isHoliday;
         }