/// <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;

         }