public void AddProduct(Product product)
{
if (!ProductsInInvoice.Exists(e => e.ID == product.ID) && product != null)
{
ProductsInInvoice.Add(product);
}
else if (product != null)
{
Product temp = ProductsInInvoice.Find(e => e.ID == product.ID);
int qauntitytemp = temp.GetProductPurchasedQuantity() + product.GetProductPurchasedQuantity();
temp.SetProductPurchasedQuantity(qauntitytemp);
int index = ProductsInInvoice.FindIndex(e => e.ID == temp.ID);
ProductsInInvoice[index] = temp;
}
}
public void RemoveProduct(int id) => ProductsInInvoice.Remove(ProductsInInvoice.Find(products => products.ID == id));
public Product GetProduct(int id)
{
return(ProductsInInvoice.Find(product => product.ID == id));
}