using System;

using System.Globalization;

public class Program

{

    public static void Main()

    {

        string cFecha=( DateTime.Now.ToString());

        Console.WriteLine(cFecha);

        CultureInfo provider = CultureInfo.InvariantCulture;  

        // It throws Argument null exception  

        DateTime dateTime10 = DateTime.ParseExact(cFecha, "F", CultureInfo.InvariantCulture);

        Console.WriteLine(dateTime10);

    }

}