hellow cw

namespace RoomBookingSystem
{
    public partial class RoomBookingForm : Form
    {
        public RoomBookingForm()
        {
            InitializeComponent();
        }

        private void RoomBookingForm_Load(object sender, EventArgs e)
        {

        }

        private void RoomBookingForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            Application.Exit();
        }

        private void BookRoomButton_Click(object sender, EventArgs e)
        {
            string Date = DateToBeBooked.Text;
            string Period = PeriodBooked.Text;
            string Email = EmailBookingRoom.Text;
            string Room = RoomBeingBooked.Text;
            string ExtraEquipment = ExtraEquipmentTextBox.Text;
            List<string> DatabaseDate = new List<string>();
            List<string> DatabasePeriod = new List<string>();

            //Selects all date records from the bookings table so that they can be compared to eliminate double bookings.
            using (SqlConnection CompareDate = new SqlConnection("RoomBookingSystem"))
            {
                string SelectDate = "SELECT DateBooked FROM Bookings";
                using (SqlCommand GetDate = new SqlCommand(SelectDate, CompareDate))
                {
                    using (SqlDataReader DateReader = GetDate.ExecuteReader())
                    {
                        while (DateReader.Read())
                        {
                            CompareDate.Open();
                            DatabaseDate.Add(DateReader.GetString(0));
                        }
                    }
                }
            }

            //Takes the date records from the bookings table in the database and puts them in a list
            if (DatabaseDate.Contains(Date))
            {
                using (SqlConnection ComparePeriod = new SqlConnection("RoomBookingSystem"))
                {
                    string SelectPeriod = "SELECT PeriodBookedFor FROM Bookings";
                    using (SqlCommand GetPeriod = new SqlCommand(SelectPeriod, ComparePeriod))
                    {
                        using (SqlDataReader DateReader = GetPeriod.ExecuteReader())
                        {
                            while (DateReader.Read())
                            {
                                ComparePeriod.Open();
                                DatabasePeriod.Add(DateReader.GetString(0));
                            }
                        }
                    }
                }

                //If the list contains the period that the user is booking for on the same date, emails the user telling them the booking was a failure
                if (DatabasePeriod.Contains(Period))
                {
                    MailMessage emailFailure = new MailMessage();
                    SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
                    emailFailure.From = new MailAddress("RoomBookingSystem@gmail.com");
                    emailFailure.To.Add(Email);
                    emailFailure.Subject = "Booking Failure";
                    emailFailure.Body = "Your recent booking failed due to the room already being booked on the same date and the same time.";


                    SmtpServer.Send(emailFailure);
                }
                else
                {
                    //Because the period booking for was different but on the same date, the booking can go through and so the details are added
                    using (SqlConnection connection = new SqlConnection("RoomBookingConnection"))
                    {
                        string SaveBooking = "INSERT INTO User(DateBooked, PeriodBooked) " + "Values('" + Date + "' , '" + Period + "')";
                        using (SqlCommand command = new SqlCommand(SaveBooking, connection))
                        {
                            connection.Open();
                            command.ExecuteNonQuery();
                        }
                    }

                    //Emails the user telling them that the booking was successful
                    MailMessage emailSuccess = new MailMessage();
                    SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
                    emailSuccess.From = new MailAddress("RoomBookingSystem@gmail.com");
                    emailSuccess.To.Add(Email);
                    emailSuccess.Subject = "Booking Success";
                    emailSuccess.Body = "Your recent booking was successful and has been added to the database.";
                    SmtpServer.Send(emailSuccess);

                    //Emails the side team for extra equipment
                    MailMessage emailSideTeam = new MailMessage();
                    SmtpClient SmtpServer2 = new SmtpClient("smtp.gmail.com");
                    emailSideTeam.From = new MailAddress("RoomBookingSystem@gmail.com");
                    emailSideTeam.To.Add("sideteam@gmail.com");
                    emailSideTeam.Subject = "Extra Equipment";
                    emailSideTeam.Body = "The user has entered this as what they would like for extra equipment " + ExtraEquipment + " in the room " + Room + " by period " + Period + ", thank you.";
                    SmtpServer2.Send(emailSideTeam);

                }
            }
            else
            {
                //Adds booking details in to the database
                using (SqlConnection connection = new SqlConnection("RoomBookingConnection"))
                {
                    string SaveBooking = "INSERT INTO User(DateBooked, PeriodBooked) " + "Values('" + Date + "' , '" + Period + "')";
                    using (SqlCommand command = new SqlCommand(SaveBooking, connection))
                    {
                        connection.Open();
                        command.ExecuteNonQuery();
                    }
                }

                //Emails the user telling them that the booking was successful
                MailMessage emailSuccess = new MailMessage();
                SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
                emailSuccess.From = new MailAddress("RoomBookingSystem@gmail.com");
                emailSuccess.To.Add(Email);
                emailSuccess.Subject = "Booking Success";
                emailSuccess.Body = "Your recent booking was successful and has been added to the database.";
                SmtpServer.Send(emailSuccess);

                //Emails the side team for extra equipment
                MailMessage emailSideTeam = new MailMessage();
                SmtpClient SmtpServer2 = new SmtpClient("smtp.gmail.com");
                emailSideTeam.From = new MailAddress("RoomBookingSystem@gmail.com");
                emailSideTeam.To.Add("sideteam@gmail.com");
                emailSideTeam.Subject = "Extra Equipment";
                emailSideTeam.Body = "The user has entered this as what they would like for extra equipment " + ExtraEquipment + " in the room " + Room + " by period " + Period + ", thank you.";
                SmtpServer2.Send(emailSideTeam);
            }
        }

        //Adds each line of the text file "Rooms" into the drop down box
        private void RoomBeingBooked_SelectedIndexChanged(object sender, EventArgs e)
        {
            string[] Rooms = File.ReadAllLines("Rooms.txt");
            foreach (var line in Rooms)
            {
                RoomBeingBooked.Items.Add(line);
            }

        }
    }
}