public void Calculate()
 {
     try
     {
         var startDate = new Core.Date(int.Parse(view.StartYear), int.Parse(view.StartMonth), int.Parse(view.StartDay));
         var endDate   = new Date(int.Parse(view.EndYear), int.Parse(view.EndMonth), int.Parse(view.EndDay));
         if (startDate > endDate)
         {
             view.Result = endDate.CalculateDifference(startDate).ToString();
             view.DisplayCustomMessageInValidationSummary("Start date after end date. Dates were Switched");
         }
         else
         {
             view.Result = startDate.CalculateDifference(endDate).ToString();
         }
     }
     catch (FormatException ex)
     {
         view.DisplayCustomMessageInValidationSummary("Please Provide numeric values in boxes");
     }
     catch (ArgumentException ex)
     {
         view.DisplayCustomMessageInValidationSummary(ex.Message);
     }
 }
 public void Calculate()
 {
     try
     {
         var startDate = new Core.Date(int.Parse(view.StartYear), int.Parse(view.StartMonth), int.Parse(view.StartDay));
         var endDate = new Date(int.Parse(view.EndYear), int.Parse(view.EndMonth), int.Parse(view.EndDay));
         if (startDate > endDate)
         {
             view.Result = endDate.CalculateDifference(startDate).ToString();
             view.DisplayCustomMessageInValidationSummary("Start date after end date. Dates were Switched");
         }
         else
         {
             view.Result = startDate.CalculateDifference(endDate).ToString();
         }
     }
     catch (FormatException ex)
     {
         view.DisplayCustomMessageInValidationSummary("Please Provide numeric values in boxes");
     }
     catch (ArgumentException ex)
     {
         view.DisplayCustomMessageInValidationSummary(ex.Message);
     }
 }