NopCommerce 4.5：计算购物车总数以创建基于客户角色的折扣

Question

I'm using NopCommerce v 4.5.3. I need to build a plugin that can create discounts to configure free shipping for certain roles for purchases beyond specified rates. Like: Free shipping above 100$ for Role A, 200$ for role B and so on.

It's to be done by creating a new discount, assigning to free shipping as discount type, giving 100% discount (for free shipping). And in the requirements, by setting the first requirement group as Required customer roles as role and by setting the second requirement group as Customer spend must be X (this is the one I am building)

There's a free plugin that sort of matches my requirement.

It calculates total orders made by the customer (the past orders) from the orders table and then lets the user set free shipping for customer. The logic used here for it is:

var orders = await _orderService.SearchOrdersAsync(request.Store.Id,
                customerId: request.Customer.Id,
                osIds: new List<int> { (int)OrderStatus.Complete });
            var spentAmount = orders.Sum(o => o.OrderTotal);
                if (spentAmount > spentAmountRequirement)

In this case, they could do it quick as they just needed to sum values in one table by using the SearchOrdersAsync() method.

But for the cart, I need to first filter the shopping cart table by using the customer ID, then taking the required productIDs from the shoppingcart and then summing up its price from the product table.

The query for it:

select sum(Price) from dbo.Product
where id in (
select ProductId
from dbo.ShoppingCartItem
where CustomerId = 2047)
--Result:1800

It's only after I get the Product IDs, that I can go to the Product table and filter them to sum up their Prices.

I've tried using the GetShoppingCartAsync() method. But I'm unable to use any lists here to store the multiple products the customer may have in cart as there's no list in the definition of GetShoppingCartAsync() while the SearchOrdersAsync() for orders has a list called osIds.

Answer 1

GetShoppingCartAsync() method returns IList<ShoppingCartItem> and the ShoppingCartItem entity contains the ProductId of a cart item. Since nopCommerce doesn't give the functionality to filter cart items by ProductIds and you need the original price of the Products, you can do the following:

Get the all the ProductIds first

var productIds = (await _shoppingCartService.GetShoppingCartAsync(customer, ShoppingCartType.ShoppingCart, storeId: store.Id)).Select(sc => sc.ProductId);

Sum the price of the products

var productPrice = (await _productService.GetProductsByIdsAsync(pIds.ToArray())).Sum(p => p.Price);

The productPrice will return the Total sum of the Products that the customer has in their cart.