/// <summary>
/// When the user clicks the Add Electronic button, if the variable existingElec
/// is null it means the electronic being added is a new one so it is added to the database.
/// If it is not null, it already exists in the database and is being updated instead.
/// </summary>
private void addElectCmd_Click(object sender, EventArgs e)
{
if (existingElec == null)
{
Electronic electToAdd = new Electronic();
electToAdd.Name = nameTxt.Text;
electToAdd.Manufacturer = manufactTxt.Text;
electToAdd.Price = Convert.ToDouble(priceTxt.Text);
electToAdd.Category = Validation.casingWords(categoryCbx.Text);
ElectronicDb.Add(electToAdd);
}
else
{
existingElec.Name = nameTxt.Text;
existingElec.Manufacturer = manufactTxt.Text;
existingElec.Price = Convert.ToDouble(priceTxt.Text);
existingElec.Category = Validation.casingWords(categoryCbx.Text);
ElectronicDb.Update(existingElec);
MessageBox.Show("Successfully updated item " + existingElec.Name);
}
Close();
}
/// <summary>
/// Adds a new electronic into the database
/// </summary>
/// <param name="elect">The electronic to add to the database</param>
/// <returns>Electronic that was added</returns>
public static Electronic Add(Electronic elect)
{
using (TrackingContext context = new TrackingContext())
{
context.Electronics.Add(elect);
context.SaveChanges();
return(elect);
}
}
/// <summary>
/// Updates an electronic that currently exists in the database
/// </summary>
/// <param name="elect">The electronic to update</param>
/// <returns>Electronic that was updated</returns>
public static Electronic Update(Electronic elect)
{
using (TrackingContext context = new TrackingContext())
{
context.Entry(elect).State = EntityState.Modified;
context.SaveChanges();
return(elect);
}
}
/// <summary>
/// Accesses the database and deletes the electronic that was passed in
/// </summary>
/// <param name="id">The id of the electronic to delete</param>
public static void Delete(int id)
{
using (TrackingContext context = new TrackingContext())
{
Electronic electDelete =
(from elect in context.Electronics
where elect.ProductId == id
select elect).Single();
context.Entry(electDelete).State = EntityState.Deleted;
context.SaveChanges();
}
}
/// <summary>
/// Populates the form with the current electronic's data, if it exists.
/// Then sets the variable existingElec to be the electronic that was passed in.
/// </summary>
/// <param name="electronic"></param>
public addElectFrm(Electronic electronic)
{
InitializeComponent();
nameTxt.Text = electronic.Name;
manufactTxt.Text = electronic.Manufacturer;
priceTxt.Text = electronic.Price.ToString();
categoryCbx.Text = electronic.Category;
addElectCmd.Text = "Update Electronic";
this.Text = "Update " + electronic.Name;
existingElec = electronic;
}
/// <summary>
/// When the Update Electronic button is pressed, open up a new form
/// with the information of that electronic already populated. The user may
/// then update any information regarding the electronic. After closing,
/// the listbox is once again repopulated. Displays an error
/// message if there is no electronic selected.
/// </summary>
private void updateElectCmd_Click(object sender, EventArgs e)
{
if (productLstBox.SelectedIndex < 0)
{
MessageBox.Show("You must choose a product to update.");
return;
}
Electronic electToUpdate = productLstBox.SelectedItem as Electronic;
addElectFrm updateForm = new addElectFrm(electToUpdate);
updateForm.ShowDialog();
populateList(ElectronicDb.GetAllElectronics());
}
/// <summary>
/// When the Delete Electronic button is pressed, a message box is
/// presented that prompts the user whether to actually delete the electronic or not.
/// If yes is clicked, then the electronic is deleted from the database. Once again,
/// the listbox is repopulated if the user clicks yes. Displays an error message if
/// there is no electronic selected.
/// </summary>
private void deleteElectCmd_Click(object sender, EventArgs e)
{
if (productLstBox.SelectedIndex < 0)
{
MessageBox.Show("You must select a product to delete.");
return;
}
Electronic elecToDelete = productLstBox.SelectedItem as Electronic;
DialogResult result = MessageBox.Show(
text: $"Are you sure you want to delete {elecToDelete.ProductId}:{elecToDelete.Manufacturer}:{elecToDelete.Name}",
caption: "Delete?",
buttons: MessageBoxButtons.YesNo,
icon: MessageBoxIcon.Warning);
if (result == DialogResult.Yes)
{
ElectronicDb.Delete(elecToDelete.ProductId);
populateList(ElectronicDb.GetAllElectronics());
}
}