using System.Globalization;
public static void Main()
DateTime searchDate = DateTime.Now;
DateTime minDate = new DateTime(2018, 12, 25);
DateTime maxDate = new DateTime(2019, 2, 28);
if(searchDate.Between(minDate, maxDate))
Console.WriteLine("{0} is between {1} --- {2}", searchDate, minDate, maxDate);
Console.WriteLine("{0} is not between {1} --- {2}", searchDate, minDate, maxDate);