public LoanCard(string idLoanCard, LibraryCards cards, DateTime thoigian, DateTime?thoigianNull)
 {
     this.IdLoanCard = idLoanCard;
     this.Cards      = cards;
     Thoigian1       = thoigian;
     ThoigianNull1   = thoigianNull;
 }
        public void AddCard()
        {
            Console.Clear();
            LibraryCards cards = new LibraryCards();

            Console.Write("- Nhap ma the: ");
            while (true)
            {
                string id    = Console.ReadLine();
                Regex  regex = new Regex(@"^[a-zA-Z0-9]+$");
                if (ListCards.FindIndex(x => x.IdCards == id) == -1)
                {
                    if (regex.IsMatch(id))
                    {
                        cards.IdCards = id;
                        break;
                    }
                    else
                    {
                        Console.WriteLine("Nhap sai!");
                        Console.Write("Nhap lai: ");
                    }
                }
                else
                {
                    Console.Write("Ma the da ton tai, nhap lai :");
                }
            }
            Console.Write("- Nhap ten chu the: ");
            while (true)
            {
                string cName = Console.ReadLine();
                Regex  regex = new Regex(@"^[a-zA-Z]+$");
                if (regex.IsMatch(cName))
                {
                    cards.CardsName = cName;
                    break;
                }
                else
                {
                    Console.WriteLine("Nhap sai! ");
                    Console.Write("Nhap lai: ");
                }
            }
            Console.Write("- Nhap so CMND: ");
            while (true)
            {
                string a     = Console.ReadLine();
                Regex  regex = new Regex(@"^[0-9]+$");
                if (ListCards.FindIndex(x => x.PeopleId == a) == -1)
                {
                    if (regex.IsMatch(a))
                    {
                        if (a.Length == 12 || a.Length == 9)
                        {
                            if (regex.IsMatch(a))
                            {
                                cards.PeopleId = a;
                                break;
                            }
                        }
                        else
                        {
                            Console.WriteLine("So CMND bao gom 9 hoac 12 so !");
                            Console.Write("Nhap lai: ");
                        }
                    }
                    else
                    {
                        Console.WriteLine("So CMND bao gom 9 hoac 12 so !");
                        Console.Write("Nhap lai: ");
                    }
                }
                else
                {
                    Console.Write("So CMND da ton tai, nhap lai :");
                }
            }
            Console.WriteLine(" ");
            Console.Write("Ban muon them the?(Y/N): ");
            string Question;

            while (true)
            {
                Question = Console.ReadLine();
                if (Question == "Y" || Question == "N" || Question == "y" || Question == "n")
                {
                    break;
                }
                else
                {
                    Console.Write("Ban muon them the?(Y/N): ");
                }
            }
            switch (Question)
            {
            case "Y":
                Console.Write("Da them the thu vien !\n");
                cards.Ngaytao1 = DateTime.Today;
                ListCards.Add(cards);
                Console.ReadKey();
                break;

            case "y":
                Console.Write("Da them the thu vien !\n");
                cards.Ngaytao1 = DateTime.Today;
                ListCards.Add(cards);
                Console.ReadKey();
                break;

            case "N":
                break;

            case "n":
                break;
            }
        }
 static public void _addCard(LibraryCards cards)
 {
     ListCards.Add(cards);
 }
        public void UpdateCards()
        {
            Console.Clear();
            LibraryCards cards = new LibraryCards();

            if (ListCards.Count == 0)
            {
                Console.WriteLine("Danh sach the thu vien trong !");
                Console.Write("Ban co muon them moi mot the ? (Y/N): ");
                string Question;
                while (true)
                {
                    Question = Console.ReadLine();
                    if (Question == "Y" || Question == "N" || Question == "y" || Question == "n")
                    {
                        break;
                    }
                    else
                    {
                        Console.Write("Ban co muon them moi mot the ? (Y/N): ");
                    }
                }
                switch (Question)
                {
                case "Y":
                    AddCard();
                    break;

                case "y":
                    AddCard();
                    break;

                case "N":
                    break;

                case "n":
                    break;
                }
            }
            else
            {
                Console.Clear();
                int item;
                Console.Write("- Nhap ma the : ");
                while (true)
                {
                    cards.IdCards = Console.ReadLine();
                    item          = ListCards.FindIndex(x => x.IdCards == cards.IdCards);
                    if (item == -1)
                    {
                        Console.WriteLine("Ma the khong ton tai !");
                        Console.Write("- Nhap ma the : ");
                    }
                    else
                    {
                        break;
                    }
                }
                Console.Write("- Sua ten chu the: ");
                while (true)
                {
                    string cName = Console.ReadLine();
                    Regex  regex = new Regex(@"^[a-zA-Z]+$");
                    if (regex.IsMatch(cName))
                    {
                        cards.CardsName = cName;
                        break;
                    }
                    else
                    {
                        Console.WriteLine("Nhap sai! ");
                        Console.Write("Nhap lai: ");
                    }
                }
                Console.Write("- Nhap so CMND: ");
                while (true)
                {
                    string a     = Console.ReadLine();
                    Regex  regex = new Regex(@"^[0-9]+$");
                    if (ListCards.FindIndex(x => x.PeopleId == a) == -1)
                    {
                        if (regex.IsMatch(a))
                        {
                            if (a.Length == 12 || a.Length == 9)
                            {
                                if (regex.IsMatch(a))
                                {
                                    cards.PeopleId = a;
                                    break;
                                }
                            }
                            else
                            {
                                Console.WriteLine("So CMND bao gom 9 hoac 12 so !");
                                Console.Write("Nhap lai: ");
                            }
                        }
                        else
                        {
                            Console.WriteLine("So CMND bao gom 9 hoac 12 so !");
                            Console.Write("Nhap lai: ");
                        }
                    }
                    else
                    {
                        Console.Write("So CMND da ton tai, nhap lai :");
                    }
                }
                Console.Write("Ban co muon sua thong tin the ? (Y/N): ");
                string Question;
                while (true)
                {
                    Question = Console.ReadLine();
                    if (Question == "Y" || Question == "N" || Question == "y" || Question == "n")
                    {
                        break;
                    }
                    else
                    {
                        Console.Write("Ban co muon sua thong tin the ? (Y/N): ");
                    }
                }
                switch (Question)
                {
                case "Y":
                    Console.WriteLine("Da sua thong tin the! ");
                    ListCards[item].CardsName = String.Copy(cards.CardsName);
                    ListCards[item].PeopleId  = String.Copy(cards.PeopleId);
                    break;

                case "y":
                    Console.WriteLine("Da sua thong tin the! ");
                    ListCards[item].CardsName = String.Copy(cards.CardsName);
                    ListCards[item].PeopleId  = String.Copy(cards.PeopleId);
                    break;

                case "n":
                    break;

                case "N":
                    break;
                }
            }
        }