using System;

using System.Globalization;

using System.Net;

public class Program

{

    public static void Main()

    {

        var val = "11 Oct 2019 10:31:55 GMT";

        DateTime expires;

        var b = DateTime.TryParse(val, CultureInfo.InvariantCulture, DateTimeStyles.AllowWhiteSpaces, out expires);

        b.Dump();

        expires.Dump();

        val = "11 Oct 2019 10:31:55 UTC";

        b = DateTime.TryParse(val, CultureInfo.InvariantCulture, DateTimeStyles.AllowTrailingWhite, out expires);

        b.Dump();

        expires.Dump();

        CookieContainer cookies1 = new CookieContainer();

        cookies1.SetCookies(new Uri("http://myuri.com"), "slt=1568B476-42EC-4ABE-8679-7C7C5AE4AABA; expires=Fri, 11 Oct 2019 10:31:55 GMT; path=/; HttpOnly; Secure");

        CookieContainer cookies2 = new CookieContainer();

        cookies2.SetCookies(new Uri("http://myuri.com"), "slt=1568B476-42EC-4ABE-8679-7C7C5AE4AABA; expires=Fri, 11 Oct 2019 10:31:55 UTC; path=/; HttpOnly; Secure");

    }

}