Get LeapYear using C#

Someone asked me yesterday how to figure out if is a leap year in c# code. It is actually not that complicated and here is how you would do it:

public static bool IsLeapYear(DateTime date)
      {
          int year = date.Year;

          if (year % 400 == 0)
              return true;
          else if (year % 100 == 0)
              return false;
          else if (year % 4 == 0)
              return true;
          else
              return false;
      }

Check for it this way:

public static int DaysInYear(DateTime date)
   {
       return IsLeapYear(date) ? 366 : 365;
   }