获取本周的周一日期与本周的周日日期

  #region 获取本周周一
        /// <summary>
        /// 获取本周的周一日期
        /// </summary>
        /// <returns></returns>
       public static string GetThisWeekMonday()  
        {  
            DateTime date = DateTime.Now;  
            DateTime firstDate = System.DateTime.Now;  
            switch (date.DayOfWeek)  
            {  
                case System.DayOfWeek.Monday:  
                   firstDate = date;  
                   break;  
               case System.DayOfWeek.Tuesday:  
                   firstDate = date.AddDays(-1);  
                   break;  
               case System.DayOfWeek.Wednesday:  
                    firstDate = date.AddDays(-2);  
                   break;  
               case System.DayOfWeek.Thursday:  
                    firstDate = date.AddDays(-3);  
                    break;  
               case System.DayOfWeek.Friday:  
                   firstDate = date.AddDays(-4);  
                  break;  
                case System.DayOfWeek.Saturday:  
                    firstDate = date.AddDays(-5);  
                    break;  
               case System.DayOfWeek.Sunday:  
                   firstDate = date.AddDays(-6);  
                  break;  
          }
            return firstDate.ToString("yyyy-MM-dd");  
       }
        #endregion

        #region  获取本周的周日
      /// <summary>
       /// 获取本周的周日日期
      /// </summary>
      /// <returns></returns>
        public static string GetThisWeekSunday()  
       {  
            DateTime date = DateTime.Now;  
            DateTime lastDate = System.DateTime.Now;  
           switch (date.DayOfWeek)  
            {  
                case System.DayOfWeek.Monday:  
                    lastDate = date.AddDays(6);  
                   break;  
                case System.DayOfWeek.Tuesday:  
                    lastDate = date.AddDays(5);  
                   break;  
                case System.DayOfWeek.Wednesday:  
                    lastDate = date.AddDays(4);  
                    break;  
                case System.DayOfWeek.Thursday:  
                    lastDate = date.AddDays(3);  
                  break;  
              case System.DayOfWeek.Friday:  
                   lastDate = date.AddDays(2);  
                    break;  
               case System.DayOfWeek.Saturday:  
                    lastDate = date.AddDays(1);  
                    break;  
                case System.DayOfWeek.Sunday:  
                    lastDate = date;  
                   break;  
           }  
          return lastDate.ToString("yyyy-MM-dd");
       }
       #endregion