Question

I have the below LINQ statement, and get the error ” ‘int’ does not contain a definition for ‘Count’ and no extension method ‘Count’ accepting a first argument of type ‘int’ could be found ( are you missing a using directive or assembly reference?) “

var queryFuture = from pqv in context.OrderPrintQueue_View
                          join od in context.Order_Details on pqv.confirmId equals od.ConfirmId
                          join pp in context.Product_Price on od.priceId equals pp.priceId
                          join p in context.Products on pp.productId equals p.ProductID
                          select new { p.stationId, inProc = 0, OrderLinesCount = od.recId.Count() };

od.recId.Count() is the portion that is returning an error. I’m very new to LINQ (have been using it for about 2 days) and am a novice programmer. The answers I have found all say to include the system.core assembly reference, and of course, the System.Linq using. I have all of those so I’m not sure what the deal is. I am using WPF with .NET 4, EF, and RIA services and the MVVM pattern.

Answer 1

recID is of type int, not IEnumerable<?>. Count() is only defined on IEnumerable<?>. You will ned a group by statement:

var queryFuture = from pqv in context.OrderPrintQueue_View
                          join od in context.Order_Details on pqv.confirmId equals od.ConfirmId
                          join pp in context.Product_Price on od.priceId equals pp.priceId
                          join p in context.Products on pp.productId equals p.ProductID
                          group od by od.recId into orders
                          select new { p.stationId, inProc = 0, OrderLinesCount = orders.Count() };

Note: I’m not sure of this combination of group by and join will work out, as I usually only use the method chains. You might have to adjust on the operators, however you’ll need a group by in any case.