/// <summary>
/// Add the specified product.
/// </summary>
/// <param name='product'>
/// Product.
/// </param>
public void add(Product product)
{
for(int i = 0; i < this.products.Count; i++) {
if(this.products[i].Id == product.Id) {
this.products[i].Amount += product.Amount;
return;
}
}
product.fillProduct();
this.products.Add(product);
}
