DevForce Community Forum : How to access nested navigation properties

How to access nested navigation properties : Anwar:I'm going to expand...

Wed, 20 Jan 2010 15:56:32 -700

Author: GregD
Subject: 1619
Posted: 20-Jan-2010 at 3:56pm

Anwar:

I'm going to expand a bit on David's answer with a couple of examples of accessing multilevel navigation properties, using entities from NorthwindIB:

anOrder.Customer.Orders

would retrieve all of the Orders (i.e., a collection) for the Customer associated with anOrder.

anOrderDetail.Product.Supplier

would return the Supplier (i.e., a scalar) associated with the Product mentioned in anOrderDetail.

When operating in an asynchronous environment like Silverlight, you will often want to be notified when retrieval of the referenced entity or entities has completed. For a collection navigation property like anOrder.Customer.Orders you would handle the PendingEntityListResolved event on the referenced property. For a scalar navigation property like anOrderlDetail.Product.Supplier you would handle the PendingEntityResolved event on the referenced property.

How to access nested navigation properties : Nested navigation properties should...

Tue, 19 Jan 2010 15:52:06 -700

Author: davidklitzke
Subject: 1619
Posted: 19-Jan-2010 at 3:52pm

Nested navigation properties should end with either a scalar (e.g., Order.Customer.FirstName) or with a list or collection (e.g., Order.Customer.Orders). If you are using a scalar, use a scalar navigation property (such as one that requires PendingEntity). If you are querying for a collection, use a collection navigation property (such as one that requires PendingEntityList).

How to access nested navigation properties : Hello All, My entity model...

Mon, 18 Jan 2010 11:43:31 -700

Author: anwar
Subject: 1619
Posted: 18-Jan-2010 at 11:43am

Hello All,

My entity model contains multilevel navigation properties, can any one help me how to access multilevel/nested navigation properties.

The sample in developer guide shows one level of navigation access. here is the code snippet from dev. guide.

// Retrieve a collection of related entities using a collection navigation property
targetOrder.OrderDetails.PendingEntityListResolved +=
new EventHandler>(

OrderDetails_PendingEntityListResolved);

void OrderDetails_PendingEntityListResolved(object sender,
PendingEntityListResolvedEventArgs e) {
Console.WriteLine("OrderDetails retrieved: {0}", e.ResolvedEntities.Count);

}

Help will be appricitated.

Thanks,

Anwar