using System.Collections.Generic;
public static void Main()
string[] s = new string[] { "one", "two", "three", "four", "five", "six" };
DateTime date = System.DateTime.ParseExact("19/11/2019", "dd/MM/YYYY".Replace("D","d").Replace("Y","y").Replace("mm","MM"), System.Globalization.DateTimeFormatInfo.InvariantInfo);
if (date <= DateTime.Now.Date)
Console.WriteLine("error " + DateTime.Now.ToShortDateString());
Console.WriteLine(date.ToString());
Console.WriteLine(DateTime.Now);