LINQ Custom OrderLine Fields in uCommerce

Question

I'm trying to count how many orderlines (ol) that have the custom field "distributedOrderLineId" equal to the orderline id of the current iteration.

The thing is, that not every orderline has this custom field defined. How can I make LINQ skip the orderlines with an undefined custom field instead of throwing an error.

Please refer to the code below.

var distributionsLeft = ol.Quantity - 1 - PurchaseOrder.All().Where(y => int.Parse(y["distributedOrderLineId"]) == ol.Id).Count();

Best regards, Brinck10

EDIT

I've tried the following piece of code using any:

PurchaseOrder.All().Where(y => y.OrderProperties.Any(z=>z.Key=="distributedOrderLineId")).Where(a=>a["distributedOrderLineId"]==ol.OrderLineId.ToString()).Count();

Unfortunately it doesn't work. The error I get on the stack trace is:

[NotSupportedException: System.String get_Item(System.String)]
   NHibernate.Linq.Visitors.HqlGeneratorExpressionTreeVisitor.VisitMethodCallExpression(MethodCallExpression expression) +206

EDIT END

Answer 1

I hope I've get what you want. I've simulated your PurchaseOrder with an array of dictionaries and I suppose, that formal parameter y in your lambda expression is derived from IDictionary, because I can see such expression y["distributedOrderLineId"]. Please correct me if I'm wrong in my assumptions. The solution is to check whether key is set by calling order.ContainsKey("id"). You can see the example below

var firstItem = new Dictionary<string, string>{{"id", "11"}};
var secondItem = new Dictionary<string, string>{{"id", "12"}};
var thirdItem = new Dictionary<string, string>(); // id is not set, as distributedOrderLineId in your example
var fourthItem = new Dictionary<string, string>{{"id", "14"}};

var PurchaseOrder = new [] {firstItem, secondItem, thirdItem, fourthItem};
var quantity = 4;
var orderID = 12;
var distributionsLeft = quantity - 1 - PurchaseOrder.Where(order => order.ContainsKey("id") && int.Parse(order["id"]) == orderID).Count();

Console.WriteLine (distributionsLeft);

Edit: Could you please try to use next query, just to see if it work? We can then try to do some optimizations if it works fine.

PurchaseOrder.Where(y => y.OrderProperties.Any(z => z.Key == "distributedOrderLineId"))
             .ToList()
             .Where(y => y["distributedOrderLineId"] == ol.OrderLineId.ToString())
             .Count();

Optimized version: I've tried to optimize version given above from performance and readability points of view, but note - I cold be wrong, because I haven't run that query. I've changed it only by analyzing uCommerce documentation regarding OrderLine and OrderProperty. Also note, that I've used different names for formal parameters in lambdas - just to get rid of mess with y and z.

string orderLineId = ol.OrderLineId.ToString();
PurchaseOrder
    .Count(order => order.OrderProperties.Any(property => property.Key == "distributedOrderLineId" && property.Value == orderLineId));

Answer 2

You can check for a specific key/value combo like so:

bool anyLinesWithKeyValue = purchaseOrder.OrderLines.Any(x => x.OrderProperties.Any(y => y.Key == "distributedOrderLineId" && y.Value == "someValue"));

That'll just give you a "yay" or "nay" on whether there are any actual lines that has that combo. If you need the order lines for something just replace "Any" with "Where".

Hope this helps.