using System;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        //var input = "27.10.2021 12:30:00";

        //Console.WriteLine(DateTime.Parse(input));

        //var input = "27.10.2021T12:30:00";

        //Console.WriteLine(DateTime.Parse(input));

        var input = "2021-10-27T12:30:00";

        Console.WriteLine(DateTime.Parse(input));

        var input2 = "27.10.2021 12:30:00";

        Console.WriteLine(DateTime.ParseExact(input2, "dd.MM.yyyy HH:mm:ss", CultureInfo.InvariantCulture));

    }

}