using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        DateTime? dt = DateTime.Now;

        var date = CrmExtensions.GetValueOrDefault(dt);

        Console.WriteLine(date.ToString());

    }

}

​

public static class CrmExtensions{

    public const string LocalTimeZone = "E. Europe Standard Time";

    public static T GetValueOrDefault<T>(T res)

        {

​

            res = ConvertGenericToLocalTimeIfIsDateTime(res);

​

            return res;

        }

    private static T ConvertGenericToLocalTimeIfIsDateTime<T>(T res)

    {

            if (res is DateTime)

            {

                DateTime dt = ((DateTime)Convert.ChangeType(res, typeof(DateTime))).ToLocalTimeCustom();

                return (T)Convert.ChangeType(dt, typeof(T));

            }

            if (res is DateTime?)

            {

                DateTime? dt = ((DateTime?)Convert.ChangeType(res, typeof(DateTime?))).ToLocalTimeCustom();

                return ((T)Convert.ChangeType(dt, typeof(T)));

            }

            return res;

    }

    public static DateTime? ToLocalTimeCustom(this DateTime? dateToConvert)

        {

            if (dateToConvert == null) return null;

​

            DateTime dt = dateToConvert.GetValueOrDefault();

            return System.TimeZoneInfo.ConvertTimeFromUtc(dt, TimeZoneInfo.FindSystemTimeZoneById(LocalTimeZone));

​

        }

​

    public static DateTime ToLocalTimeCustom(this DateTime dateToConvert)

    {

        return System.TimeZoneInfo.ConvertTimeFromUtc(dateToConvert, TimeZoneInfo.FindSystemTimeZoneById(LocalTimeZone));

​

    }

}