Question

I’m using Entity Framework but I’ve cached some application wide entities, so now they’re List rather than entities.

Two of the objects I’ve cached are Products and Stores – a Product has a store. In a table they are linked by StoreId, but since I’m using EF the Product can also include the Store entity.

I don’t cache them together simply because they are also used independently. What I would like to do is join them at some point, so I might subselect the Product object then want to populate Stores by joining the Stores object.

Is the most efficient way of joining 2 lists using linq – if so whats the most efficient syntax, or is there’s a better way converting lists back to entities.

Answer 1

is there a better way of converting lists back to entities

This is a bit misleading as this isn’t what your trying to do. You pull down a list of Products/Stores which are entities – no need to convert them (even if your storing them in a list).

If I understand you correctly what you want to do is basically map each Product to it’s appropriate Store from the cached entities (to save going back to the DB by accessing the Store property on the Product entity). I am pretty sure all you need to do is map this across, so something like:

foreach (var product in cachedProducts)
{
    product.Store = cachedStores.SingleOrDefault(s => s.Id == product.StoreId);
}