Delete customer, modify and add almost work

C969Project/AddUpdateCustomerForm.cs

@@ -1,32 +1,43 @@
+using C969Project.Data;
 using C969Project.Data.Models;
 
 namespace C969Project;
 
 public partial class AddUpdateCustomerForm : Form
 {
-    public enum OperationType { Add, Update }
+    public AddUpdateCustomerForm()
-    public AddUpdateCustomerForm(OperationType operationType, Customer? customer = null)
     {
         InitializeComponent();
-
-        if (operationType == OperationType.Add) InitAdd();
-        else if (operationType == OperationType.Update && customer is not null) InitUpdate(customer);
-        else Close();
-
     }
 
-    private void InitAdd()
+    public void InitAdd()
     {
         Text = "Add Customer";
         label1.Text = "Add Customer";
+        
+        nameTextBox.Text = string.Empty;
+        addressTextBox.Text = string.Empty;
+        cityTextBox.Text = string.Empty;
+        zipTextBox.Text = string.Empty;
+        phoneTextBox.Text = string.Empty;
+
+        ShowDialog();
     }
 
-    private void InitUpdate(Customer customer)
+    public void InitUpdate(Customer customer)
     {
         Text = "Update Customer";
         label1.Text = "Update Customer";
 
         nameTextBox.Text = customer.CustomerName;
+        var addr = DatabaseHelper.RetrieveAddress(customer.AddressId);
+        addressTextBox.Text = addr.Address1;
+        var city = DatabaseHelper.RetrieveCity(addr.CityId);
+        cityTextBox.Text = city.CityName;
+        zipTextBox.Text = addr.PostalCode;
+        phoneTextBox.Text = addr.Phone;
+        
+        ShowDialog();
     }
     
     // name, {address, phone}

C969Project/Data/DatabaseHelper.cs

@@ -24,8 +24,10 @@ public static class DatabaseHelper
             Console.WriteLine(ex.Message);
         }
         
-        string query = $"SELECT * FROM client_schedule.user WHERE userName = '{username}'";
+        string query = "SELECT * FROM client_schedule.user WHERE userName = @username";
         using MySqlCommand command = new MySqlCommand(query, connection);
+        command.Parameters.AddWithValue("@username", username);
+
         using MySqlDataReader reader = command.ExecuteReader();
 
         while (reader.Read())
@@ -102,7 +104,7 @@ public static class DatabaseHelper
             command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
             command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
             
-            int rowsAffected = command.ExecuteNonQuery();
+            command.ExecuteNonQuery();
         }
         catch (MySqlException e)
         {
@@ -116,6 +118,68 @@ public static class DatabaseHelper
         }
     }
 
+    public static void UpdateCustomer(Customer customer)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "UPDATE customer SET customerName = @customerName, addressId = @addressId, active = @active, " +
+                "lastUpdate = @lastUpdate, lastUpdateBy = @lastUpdateBy WHERE customerId = @customerId";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@customerName", customer.CustomerName);
+            command.Parameters.AddWithValue("@addressId", customer.AddressId);
+            command.Parameters.AddWithValue("@active", customer.Active);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@customerId", customer.CustomerId);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+    
+    public static void DeleteCustomer(int customerId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+            string query = "DELETE FROM customer WHERE customerId = @customerId";
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            command.Parameters.AddWithValue("@customerId", customerId);
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw;
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteCustomer(Customer customer)
+    {
+        DeleteCustomer(customer.CustomerId);
+    }
+    
     public static Address? RetrieveAddress(int addressId)
     {
         using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
@@ -129,8 +193,10 @@ public static class DatabaseHelper
             throw;
         }
         
-        string query = $"SELECT * FROM client_schedule.address WHERE addressId = {addressId}";
+        string query = "SELECT * FROM client_schedule.address WHERE addressId = @addressId";
         using MySqlCommand command = new MySqlCommand(query, connection);
+        command.Parameters.AddWithValue("@addressId", addressId);
+
         using MySqlDataReader reader = command.ExecuteReader();
         
         while (reader.Read())
@@ -138,7 +204,7 @@ public static class DatabaseHelper
             var addr = new Address()
             {
                 Id = reader.GetInt32("addressId"),
-                Address1 = reader.GetString("address1"),
+                Address1 = reader.GetString("address"),
                 Address2 = reader.GetString("address2"),
                 CityId = reader.GetInt32("cityId"),
                 PostalCode = reader.GetString("postalCode"),
@@ -154,4 +220,684 @@ public static class DatabaseHelper
         
         return null;
     }
+
+    public static List<Address> RetrieveAllAddresses()
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        List<Address> addresses = new List<Address>();
+        
+        using MySqlCommand command = new MySqlCommand("SELECT * FROM client_schedule.address", connection);
+        using MySqlDataReader reader = command.ExecuteReader();
+        while (reader.Read())
+        {
+            var addr = new Address()
+            {
+                Id = reader.GetInt32("addressId"),
+                Address1 = reader.GetString("address"),
+                Address2 = reader.GetString("address2"),
+                CityId = reader.GetInt32("cityId"),
+                PostalCode = reader.GetString("postalCode"),
+                Phone = reader.GetString("phone"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            addresses.Add(addr);
+        }
+        
+        return addresses;
+    }
+
+    public static void AddAddress(Address address)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "INSERT INTO address (addressId, address, address2, cityId, postalCode, phone, createDate, createdBy, lastUpdate, lastUpdateBy) " +
+                "VALUES (@addressId, @address1, @address2, @cityId, @postalCode, @phone, @createDate, @createdBy, @lastUpdate, @lastUpdateBy)";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@addressId", address.Id);
+            command.Parameters.AddWithValue("@address1", address.Address1);
+            command.Parameters.AddWithValue("@address2", address.Address2);
+            command.Parameters.AddWithValue("@cityId", address.CityId);
+            command.Parameters.AddWithValue("@postalCode", address.PostalCode);
+            command.Parameters.AddWithValue("@phone", address.Phone);
+            command.Parameters.AddWithValue("@createDate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@createdBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void UpdateAddress(Address address)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "UPDATE address SET address = @address1, address2 = @address2, cityId = @cityId, postalCode = @postalCode, " +
+                "phone = @phone, lastUpdate = @lastUpdate, lastUpdateBy = @lastUpdateBy WHERE addressId = @addressId";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@address1", address.Address1);
+            command.Parameters.AddWithValue("@address2", address.Address2);
+            command.Parameters.AddWithValue("@cityId", address.CityId);
+            command.Parameters.AddWithValue("@postalCode", address.PostalCode);
+            command.Parameters.AddWithValue("@phone", address.Phone);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@addressId", address.Id);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteAddress(int addressId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+            string query = "DELETE FROM address WHERE addressId = @addressId";
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            command.Parameters.AddWithValue("@addressId", addressId);
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw;
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteAddress(Address address)
+    {
+        DeleteAddress(address.Id);
+    }
+
+    public static Appointment? RetrieveAppointment(int appointmentId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        string query = "SELECT * FROM client_schedule.appointment WHERE appointmentId = @appointmentId";
+        using MySqlCommand command = new MySqlCommand(query, connection);
+        command.Parameters.AddWithValue("@appointmentId", appointmentId);
+
+        using MySqlDataReader reader = command.ExecuteReader();
+        
+        while (reader.Read())
+        {
+            var appt = new Appointment()
+            {
+                AppointmentId = reader.GetInt32("appointmentId"),
+                CustomerId = reader.GetInt32("customerId"),
+                UserId = reader.GetInt32("userId"),
+                Title = reader.GetString("title"),
+                Description = reader.GetString("description"),
+                Location = reader.GetString("location"),
+                Contact = reader.GetString("contact"),
+                AppointmentType = reader.GetString("type"),
+                Url = reader.GetString("url"),
+                Start = reader.GetDateTime("start"),
+                End = reader.GetDateTime("end"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            return appt;
+        }
+        
+        return null;
+    }
+
+    public static List<Appointment> RetrieveAllAppointments()
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        List<Appointment> appointments = new List<Appointment>();
+        
+        using MySqlCommand command = new MySqlCommand("SELECT * FROM client_schedule.appointment", connection);
+        using MySqlDataReader reader = command.ExecuteReader();
+        while (reader.Read())
+        {
+            var appt = new Appointment()
+            {
+                AppointmentId = reader.GetInt32("appointmentId"),
+                CustomerId = reader.GetInt32("customerId"),
+                UserId = reader.GetInt32("userId"),
+                Title = reader.GetString("title"),
+                Description = reader.GetString("description"),
+                Location = reader.GetString("location"),
+                Contact = reader.GetString("contact"),
+                AppointmentType = reader.GetString("type"),
+                Url = reader.GetString("url"),
+                Start = reader.GetDateTime("start"),
+                End = reader.GetDateTime("end"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            appointments.Add(appt);
+        }
+        
+        return appointments;
+    }
+
+    public static void AddAppointment(Appointment appointment)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "INSERT INTO appointment (appointmentId, customerId, userId, title, description, location, contact, type, url, start, end, createDate, createdBy, lastUpdate, lastUpdateBy) " +
+                "VALUES (@appointmentId, @customerId, @userId, @title, @description, @location, @contact, @type, @url, @start, @end, @createDate, @createdBy, @lastUpdate, @lastUpdateBy)";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@appointmentId", appointment.AppointmentId);
+            command.Parameters.AddWithValue("@customerId", appointment.CustomerId);
+            command.Parameters.AddWithValue("@userId", appointment.UserId);
+            command.Parameters.AddWithValue("@title", appointment.Title);
+            command.Parameters.AddWithValue("@description", appointment.Description);
+            command.Parameters.AddWithValue("@location", appointment.Location);
+            command.Parameters.AddWithValue("@contact", appointment.Contact);
+            command.Parameters.AddWithValue("@type", appointment.AppointmentType);
+            command.Parameters.AddWithValue("@url", appointment.Url);
+            command.Parameters.AddWithValue("@start", appointment.Start);
+            command.Parameters.AddWithValue("@end", appointment.End);
+            command.Parameters.AddWithValue("@createDate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@createdBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void UpdateAppointment(Appointment appointment)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "UPDATE appointment SET customerId = @customerId, userId = @userId, title = @title, description = @description, " +
+                "location = @location, contact = @contact, type = @type, url = @url, start = @start, end = @end, " +
+                "lastUpdate = @lastUpdate, lastUpdateBy = @lastUpdateBy WHERE appointmentId = @appointmentId";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@customerId", appointment.CustomerId);
+            command.Parameters.AddWithValue("@userId", appointment.UserId);
+            command.Parameters.AddWithValue("@title", appointment.Title);
+            command.Parameters.AddWithValue("@description", appointment.Description);
+            command.Parameters.AddWithValue("@location", appointment.Location);
+            command.Parameters.AddWithValue("@contact", appointment.Contact);
+            command.Parameters.AddWithValue("@type", appointment.AppointmentType);
+            command.Parameters.AddWithValue("@url", appointment.Url);
+            command.Parameters.AddWithValue("@start", appointment.Start);
+            command.Parameters.AddWithValue("@end", appointment.End);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@appointmentId", appointment.AppointmentId);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteAppointment(int appointmentId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+            string query = "DELETE FROM appointment WHERE appointmentId = @appointmentId";
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            command.Parameters.AddWithValue("@appointmentId", appointmentId);
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw;
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteAppointment(Appointment appointment)
+    {
+        DeleteAppointment(appointment.AppointmentId);
+    }
+
+    public static City? RetrieveCity(int cityId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        string query = "SELECT * FROM client_schedule.city WHERE cityId = @cityId";
+        using MySqlCommand command = new MySqlCommand(query, connection);
+        command.Parameters.AddWithValue("@cityId", cityId);
+
+        using MySqlDataReader reader = command.ExecuteReader();
+        
+        while (reader.Read())
+        {
+            var city = new City()
+            {
+                CityID = reader.GetInt32("cityId"),
+                CityName = reader.GetString("city"),
+                CountryID = reader.GetInt32("countryId"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            return city;
+        }
+        
+        return null;
+    }
+
+    public static List<City> RetrieveAllCities()
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        List<City> cities = new List<City>();
+        
+        using MySqlCommand command = new MySqlCommand("SELECT * FROM client_schedule.city", connection);
+        using MySqlDataReader reader = command.ExecuteReader();
+        while (reader.Read())
+        {
+            var city = new City()
+            {
+                CityID = reader.GetInt32("cityId"),
+                CityName = reader.GetString("city"),
+                CountryID = reader.GetInt32("countryId"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            cities.Add(city);
+        }
+        
+        return cities;
+    }
+
+    public static void AddCity(City city)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "INSERT INTO city (cityId, city, countryId, createDate, createdBy, lastUpdate, lastUpdateBy) " +
+                "VALUES (@cityId, @cityName, @countryId, @createDate, @createdBy, @lastUpdate, @lastUpdateBy)";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@cityId", city.CityID);
+            command.Parameters.AddWithValue("@cityName", city.CityName);
+            command.Parameters.AddWithValue("@countryId", city.CountryID);
+            command.Parameters.AddWithValue("@createDate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@createdBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void UpdateCity(City city)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "UPDATE city SET city = @cityName, countryId = @countryId, " +
+                "lastUpdate = @lastUpdate, lastUpdateBy = @lastUpdateBy WHERE cityId = @cityId";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@cityName", city.CityName);
+            command.Parameters.AddWithValue("@countryId", city.CountryID);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@cityId", city.CityID);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteCity(int cityId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+            string query = "DELETE FROM city WHERE cityId = @cityId";
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            command.Parameters.AddWithValue("@cityId", cityId);
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw;
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteCity(City city)
+    {
+        DeleteCity(city.CityID);
+    }
+
+    public static Country? RetrieveCountry(int countryId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        string query = "SELECT * FROM client_schedule.country WHERE countryId = @countryId";
+        using MySqlCommand command = new MySqlCommand(query, connection);
+        command.Parameters.AddWithValue("@countryId", countryId);
+
+        using MySqlDataReader reader = command.ExecuteReader();
+        
+        while (reader.Read())
+        {
+            var country = new Country()
+            {
+                CountryID = reader.GetInt32("countryId"),
+                CountryName = reader.GetString("country"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            return country;
+        }
+        
+        return null;
+    }
+
+    public static List<Country> RetrieveAllCountries()
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine(e);
+            throw;
+        }
+        
+        List<Country> countries = new List<Country>();
+        
+        using MySqlCommand command = new MySqlCommand("SELECT * FROM client_schedule.country", connection);
+        using MySqlDataReader reader = command.ExecuteReader();
+        while (reader.Read())
+        {
+            var country = new Country()
+            {
+                CountryID = reader.GetInt32("countryId"),
+                CountryName = reader.GetString("country"),
+                CreateDate = reader.GetDateTime("createDate"),
+                CreatedBy = reader.GetString("createdBy"),
+                LastUpdate = reader.GetDateTime("lastUpdate"),
+                LastUpdateBy = reader.GetString("lastUpdateBy"),
+            };
+            
+            countries.Add(country);
+        }
+        
+        return countries;
+    }
+
+    public static void AddCountry(Country country)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "INSERT INTO country (countryId, country, createDate, createdBy, lastUpdate, lastUpdateBy) " +
+                "VALUES (@countryId, @countryName, @createDate, @createdBy, @lastUpdate, @lastUpdateBy)";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@countryId", country.CountryID);
+            command.Parameters.AddWithValue("@countryName", country.CountryName);
+            command.Parameters.AddWithValue("@createDate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@createdBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void UpdateCountry(Country country)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+
+            string query = 
+                "UPDATE country SET country = @countryName, " +
+                "lastUpdate = @lastUpdate, lastUpdateBy = @lastUpdateBy WHERE countryId = @countryId";
+            
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            
+            command.Parameters.AddWithValue("@countryName", country.CountryName);
+            command.Parameters.AddWithValue("@lastUpdate", DateTime.UtcNow);
+            command.Parameters.AddWithValue("@lastUpdateBy", AppState.CurrentUser.Username);
+            command.Parameters.AddWithValue("@countryId", country.CountryID);
+            
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw; 
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteCountry(int countryId)
+    {
+        using MySqlConnection connection = new MySqlConnection(AppSettings.GetSetting("ConnectionStrings", "DefaultConnection"));
+        try
+        {
+            connection.Open();
+            string query = "DELETE FROM country WHERE countryId = @countryId";
+            using MySqlCommand command = new MySqlCommand(query, connection);
+            command.Parameters.AddWithValue("@countryId", countryId);
+            command.ExecuteNonQuery();
+        }
+        catch (MySqlException e)
+        {
+            Console.WriteLine($"MySQL Error: {e.Message}");
+            throw;
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"General Error: {ex.Message}");
+            throw;
+        }
+    }
+
+    public static void DeleteCountry(Country country)
+    {
+        DeleteCountry(country.CountryID);
+    }
 }

C969Project/LoginForm.cs

@@ -35,7 +35,7 @@ namespace C969Project
             AppState.CurrentUser = usr;
 
             var dash = new DashboardForm();
-            dash.FormClosing += (o, args) => { this.Show(); };
+            dash.FormClosing += (o, args) => { Close(); };
             dash.Show();
             Hide();
         }

C969Project/RecordsForm.cs

@@ -6,16 +6,39 @@ namespace C969Project;
 public partial class RecordsForm : Form
 {
     private List<Customer>? _customers;
+    private AddUpdateCustomerForm _form = new(); 
     
     public RecordsForm()
     {
         InitializeComponent();
         UpdateCustomersList();
 
-        AddButton.Click += (sender, args) => { ShowDialog(new AddUpdateCustomerForm(AddUpdateCustomerForm.OperationType.Add)); };
+        AddButton.Click += (sender, args) =>
-        ModifyButton.Click += (sender, args) => { ShowDialog(new AddUpdateCustomerForm(AddUpdateCustomerForm.OperationType.Update)); };
+        {
+            _form.InitAdd();
+        };
+        
+        ModifyButton.Click += (sender, args) =>
+        {
+            var selectedCustomer = _customers[CustomersDataGrid.CurrentCell.RowIndex];
+            _form.InitUpdate(selectedCustomer);
+        };
+
+        DeleteButton.Click += (sender, args) =>
+        {
+            var selectedCustomer = _customers[CustomersDataGrid.CurrentCell.RowIndex];
+            var result = MessageBox.Show("Are you sure you want to delete this record?", "Delete Record", MessageBoxButtons.OKCancel, MessageBoxIcon.Question);
+            if (result == DialogResult.OK)
+            {
+                _customers.Remove(selectedCustomer);
+                DatabaseHelper.DeleteCustomer(selectedCustomer);
+                UpdateCustomersList();
+            }
+        };
     }
     
+    
+
     public void UpdateCustomersList()
     {
         if (_customers != null && _customers.Count > 0) _customers.Clear();