static void Main(string[] args)
{
//NorthwindDataContext context = new NorthwindDataContext(new Uri("http://localhost:12345/Northwind.svc"));
NorthwindDataContext context = new NorthwindDataContext(new Uri("http://localhost:54321/Northwind.svc"));
var order = (from o in context.Orders.Expand("Order_Details")
where o.OrderID == 10248
select o).FirstOrDefault();
var item = order.Order_Details.FirstOrDefault();
item.Quantity += 1;
context.UpdateObject(item);
context.SaveChanges();
context.DeleteObject(item);
context.SaveChanges();
context.AddRelatedObject(order, "Order_Details", item);
context.SaveChanges();
}