c969-project/C969Project/Forms/CustomersForm.cs

using C969Project.Data;
using C969Project.Data.Models;

namespace C969Project;

public partial class CustomersForm : Form
{
    private List<Customer>? _customers;
    private AddUpdateCustomerForm _form = new(); 
    
    public CustomersForm()
    {
        InitializeComponent();
        UpdateCustomersList(null, EventArgs.Empty);

        Shown += UpdateCustomersList;
        
        _form.UpdateCustomersList += UpdateCustomersList;

        AddButton.Click += (sender, args) =>
        {
            _form.InitAdd();
        };
        
        ModifyButton.Click += (sender, args) =>
        {
            if (_customers is null) return;
            var selectedCustomer = _customers[CustomersDataGrid.CurrentCell.RowIndex];
            _form.InitUpdate(selectedCustomer);
        };

        DeleteButton.Click += (sender, args) =>
        {
            if (CustomersDataGrid.CurrentCell is null || CustomersDataGrid.CurrentCell.RowIndex > _customers?.Count)
            {
                MessageBox.Show("Please select a customer to delete");
                return;
            }
            
            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(null, EventArgs.Empty);
            }
        };
    }

    public void UpdateCustomersList(object? sender, EventArgs args)
    {
        if (_customers != null && _customers.Count > 0) _customers.Clear(); 
        _customers = DatabaseHelper.RetrieveCustomers();
        CustomersDataGrid.DataSource = _customers;
    }
}