//Find index of product.
public int FindIndex(string productName)
{
int index = OrderItems.FindIndex(x => x.ProductName == productName);
if (index <= -1)
{
throw new KeyNotFoundException("Product Name Not Found");
}
return(index);
}
public void UpdateItems(OrderItem orderItem)
{
int index = OrderItems.FindIndex(item => item.Commodity.Equals(orderItem.Commodity));
if (index == -1)
{
OrderItems.Add(orderItem.DeepClone());
}
else
{
OrderItems[index].Quantity += orderItem.Quantity;
if (OrderItems[index].Quantity <= 0)
{
Delete(OrderItems[index]);
}
}
}