public Kupac(SqlDataReader reader)
{
KupacId = Convert.ToInt32(reader[\"KupacId\"]);
Ime = reader[\"Ime\"].ToString();
Prezime = reader[\"Prezime\"].ToSt
You might need to specify culture
ClanOd = DateTime.ParseExact(reader["ClanOd"], "dd.MM.yyyy", System.Globalization.CultureInfo.GetCultureInfo("de-DE"));
Or try this:
System.Globalization.CultureInfo cultureInfo = new System.Globalization.CultureInfo("de-DE");
ClanOd = DateTime.Parse(reader["ClanOd"], cultureInfo);