var publicHolidays = DateSystem.GetPublicHoliday("DE", 2017);
foreach (var publicHoliday in publicHolidays)
{
	//publicHoliday...
}

var startDate = new DateTime(2016, 5, 1);
var endDate = new DateTime(2018, 5, 31);
var publicHolidays = DateSystem.GetPublicHoliday(CountryCode.DE, startDate, endDate);
foreach (var publicHoliday in publicHolidays)
{
	//publicHoliday...
}

var date = new DateTime(2017, 1, 1);
if (DateSystem.IsPublicHoliday(date, CountryCode.DE))
{
	Console.WriteLine("Is public holiday");
}

var date = new DateTime(2017, 1, 1);
if (DateSystem.IsWeekend(date, CountryCode.DE))
{
	Console.WriteLine("Is weekend");
}

var date = new DateTime(1900, 1, 1);
var age = DateSystem.GetAge(date);