How to iterate an Entity Framework tree to find a specific item

I have loaded my product catalog using Entity Framework

I would like to iterate all items to find a specific item the structure is Category -> [Subcategory ->] Product -> options Subcategory, product and options are EntityCollection of their spe开发者_如何学Ccific type All types derive from EntityObject

Let's say I'm looking for option 12 but I don't know in which product it is in.

How can I iterate all objects to find the option 12 ? I have this so far. in my EntityObject, I know it's not recursive yet but will eventually be once i know which properties are collections, I might be approaching it the wrong way ...

public T Find<T>(Type type, int id) where T : EntityObject
        {    
            //get all properties 
            PropertyInfo[] properties = this.GetType().GetProperties();
            // foreach property find the one
            foreach (PropertyInfo oPropertyInfo in properties)
            {
                // check for type
                if (oPropertyInfo.PropertyType == type)
                {
                    PersistentEntity o = oPropertyInfo.GetValue(this, null) as EntityObject;
                    if (o != null && o.Id == id)
                    {
                        return (T)o;
                    }                        
                }
                // if property has childs, is IEnumerable -> recursive
            }


            return (T)new EntityObject();
        }

How about this?

var query = 
from c in categories
from sc in c.SubCategories
from from p in sc.Products
from o in p.Options
where o.Id == 2
select c /* or p?? */;