WinForms Data Grid - Display many-to-many Entity Framework object relationship

C#
using System;
using System.Linq;
using System.Data.Objects;
using System.Windows.Forms;
using DevExpress.XtraEditors;

namespace DXSample {
    public partial class Form1 : XtraForm {
        NorthwindEntities northwind;
        public Form1() {
            InitializeComponent();
            northwind = new NorthwindEntities();
            ObjectQuery<Product> productsQuery = northwind.Products.Include("Order_Details.Order");
            gridControl1.DataSource = new BindingSource(productsQuery, "");
        }

        private void OnMasterRowEmpty(object sender, DevExpress.XtraGrid.Views.Grid.MasterRowEmptyEventArgs e) {
            Product p = (Product)gridView1.GetRow(e.RowHandle);
            e.IsEmpty = p.Order_Details.Count == 0;
        }

        private void OnMasterRowGetRelationCount(object sender, DevExpress.XtraGrid.Views.Grid.MasterRowGetRelationCountEventArgs e) {
            e.RelationCount = 1;
        }

        private void OnMasterRowGetRelationName(object sender, DevExpress.XtraGrid.Views.Grid.MasterRowGetRelationNameEventArgs e) {
            e.RelationName = "Orders";
        }

        private void OnMasterRowGetChildList(object sender, DevExpress.XtraGrid.Views.Grid.MasterRowGetChildListEventArgs e) {
            Product p = (Product)gridView1.GetRow(e.RowHandle);
            e.ChildList = p.Order_Details.Select(od => od.Order).Distinct().ToList(); ;
        }
    }
}

Visual Basic
Imports Microsoft.VisualBasic
Imports System
Imports System.Linq
Imports System.Data.Objects
Imports System.Windows.Forms
Imports DevExpress.XtraEditors

Namespace DXSample
    Partial Public Class Form1
        Inherits XtraForm
        Private northwind As NorthwindEntities
        Public Sub New()
            InitializeComponent()
            northwind = New NorthwindEntities()
            Dim productsQuery As ObjectQuery(Of Product) = northwind.Products.Include("Order_Details.Order")
            gridControl1.DataSource = New BindingSource(productsQuery, "")
        End Sub

        Private Sub OnMasterRowEmpty(ByVal sender As Object, ByVal e As DevExpress.XtraGrid.Views.Grid.MasterRowEmptyEventArgs) Handles gridView1.MasterRowEmpty
            Dim p As Product = CType(gridView1.GetRow(e.RowHandle), Product)
            e.IsEmpty = p.Order_Details.Count = 0
        End Sub

        Private Sub OnMasterRowGetRelationCount(ByVal sender As Object, ByVal e As DevExpress.XtraGrid.Views.Grid.MasterRowGetRelationCountEventArgs) Handles gridView1.MasterRowGetRelationCount
            e.RelationCount = 1
        End Sub

        Private Sub OnMasterRowGetRelationName(ByVal sender As Object, ByVal e As DevExpress.XtraGrid.Views.Grid.MasterRowGetRelationNameEventArgs) Handles gridView1.MasterRowGetRelationName
            e.RelationName = "Orders"
        End Sub

        Private Sub OnMasterRowGetChildList(ByVal sender As Object, ByVal e As DevExpress.XtraGrid.Views.Grid.MasterRowGetChildListEventArgs) Handles gridView1.MasterRowGetChildList
            Dim p As Product = CType(gridView1.GetRow(e.RowHandle), Product)
            e.ChildList = p.Order_Details.Select(Function(od) od.Order).Distinct().ToList()

        End Sub
    End Class
End Namespace