Can I load hierarchical data with Entity Framework 4 using ".Include" and filter a Navigation Property based on some criteria

Hello I am using entity framework 4 and I am trying to query Customers and their Orders as navigation property, but I only want to load the orders of a specific date.

When using this:

List<Customer> CustomerResults = ctx.Customers
.Include("Orders") 
.Where(
       c =>
       c.Orders.Any(od =>(od.DateTimeIn >= this.StartDateComboBox.DateTime && 
       od.DateTimeIn <= this.EndDateComboBox.DateTime))
      );
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I get all Orders, if any of the Orders meet the criteria.

Is It possible to filter the navigation property to return only rows that meet specific criteria?

---

No, there isn't.

In short, eager-loading with Include automatically loads all related records (think a LEFT OUTER JOIN without a filter).

Anytime you want to filter associated records, don't use Include - use an anonymous type projection and EF will just "work out" what needs to be retrieved:

var CustomerResults = ctx.Customers 
                         .Select(x => new
                         {
                            Customer = x,
                            Orders = x.Orders.Where(y => y.DateTimeIn > value)
                         }).ToList();

If you want to return a Customer entity, then just do another projection at the end, just make sure you materialize the query first (.ToList()).

EDIT - To put back into a customer object, example:

var Customers = new List<Customer>();
foreach (var anonType in CustomerResults)
{
   Customer c = anonType.Customer;
   c.Orders = anonType.Orders;
   Customers.Add(c);
}

I'm sure you can do that with a LINQ expression, but i can't remember the syntax.