private void btnAddProduct_Click(object sender, EventArgs e)
{
Dialogs.FrmItemBox dialog = new Dialogs.FrmItemBox(Dialogs.FrmItemBox.ItemOperation.Add);
if (dialog.ShowDialog() == DialogResult.OK)
{
var product = dialog.Product;
viewModel.AddProduct(product.Name, product.BuyingPrice, product.SellingPrice);
}
}