The following example demonstrates how to bind a grid to an SQL LINQ query and submit any modifications made to the data items using the SubmitChanges method. 

Although existing data items can be modified and the changes committed, it is not possible to insert new data items.

This example assumes that a new LINQ to SQL Classes item named Northwind.dbml has been added to the project and that it contains the Orders, Customers, and Shippers tables. The Northwind.designer.cs that is created at the same time represents the NorthwindDataContext and should automatically contain all the relevant members. It also assumes that a property named OrdersQuery that returns a new new query based on the value selected in the combo box.

The Window1 class implements INotifyPropertyChanged so that the DataGridCollectionViewSource can be notified when the query changes in order to refresh its content.

For more information on LINQ, refer to The LINQ Project Web site.

XAML
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<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"

      xmlns:local="clr-namespace:Xceed.Wpf.Documentation">

  <Grid.Resources>

    <xcdg:DataGridCollectionViewSource x:Key="cvs_orders"

                                      Source="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}},

                                                       Path=OrdersQuery}">

      <xcdg:DataGridCollectionViewSource.GroupDescriptions>

        <xcdg:DataGridGroupDescription PropertyName="Shipper"/>

      </xcdg:DataGridCollectionViewSource.GroupDescriptions>

    </xcdg:DataGridCollectionViewSource>

    <DataTemplate DataType="{x:Type local:Shipper}">

      <TextBlock Text="{Binding CompanyName}"/>

    </DataTemplate>

    <DataTemplate DataType="{x:Type local:Customer}">

      <TextBlock Text="{Binding CompanyName}"/>

    </DataTemplate>

    <DataTemplate DataType="{x:Type local:Employee}">

      <StackPanel Orientation="Horizontal">

        <TextBlock Text="{Binding FirstName}"/>

        <TextBlock Text=" " />

        <TextBlock Text="{Binding LastName}"/>

      </StackPanel>

    </DataTemplate>       

  </Grid.Resources>

  <DockPanel>

    <StackPanel Orientation="Horizontal"

                DockPanel.Dock="Top">

      <Button Content="Save Modifications"

              Click="SaveModifications"/>

      <ComboBox x:Name="ShipperCombo"

                ItemsSource="{Binding Source={x:Static Application.Current}, Path=LinqDataContext.Shippers}"

                SelectionChanged="ShipperSelectionChanged"/>

    </StackPanel>

    <xcdg:DataGridControl x:Name="OrdersGrid"

                          ItemsSource="{Binding Source={StaticResource cvs_orders}}">

      <xcdg:DataGridControl.Columns>

        <xcdg:Column FieldName="Shipper"

                     VisiblePosition="0"/>

        <xcdg:Column FieldName="OrderID"

                     Visible="False"/>

        <xcdg:Column FieldName="EmployeeID"

                     Visible="False"/>

        <xcdg:Column FieldName="CustomerID"

                     Visible="False"/>

        <xcdg:Column FieldName="Customer"

                     Title="Company Name"/>

        <xcdg:Column FieldName="ShipVia"

                     Visible="False"/>

      </xcdg:DataGridControl.Columns>

    </xcdg:DataGridControl>

  </DockPanel>

</Grid>
VB.NET
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Namespace Xceed.Wpf.Documentation

Public Partial Class Window1

    Inherits Window

    Implements INotifyPropertyChanged

    Public Sub New()

      InitializeComponent()

    End Sub

    Private m_query As IEnumerable = Nothing

    Public Property OrdersQuery() As IEnumerable

      Get

        If m_query Is Nothing Then

          m_query = From orders In App.LinqDataContext.Orders _

                    Select orders

        End If

        Return m_query

      End Get

      Set

        m_query = Value

        Me.OnPropertyChanged(New PropertyChangedEventArgs("OrdersQuery"))

      End Set

    End Property

    Private Sub ShipperSelectionChanged(ByVal sender As Object, ByVal e As SelectionChangedEventArgs)

      Me.OrdersQuey = From orders In App.LinqDataContext.Orders _

                 Where orders.Shipper.CompanyName = CTYpe( Me.ShipperCombo.SelectedValue, Shipper).CompanyName _

                 Select orders

    End Sub

    Private Sub SaveModifications(ByVal sender As Object, ByVal e As RoutedEventArgs)

      App.LinqDataContext.SubmitChanges()

    End Sub

    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    Private Sub OnPropertyChanged(ByVal e As PropertyChangedEventArgs)

      If Me.PropertyChangedEvent Is Nothing Then

        Return

      End If

      RaiseEvent PropertyChanged(Me, e)

    End Sub

  End Class

End Namespace
C#
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namespace Xceed.Wpf.Documentation

{

 public partial class Window1 : Window, INotifyPropertyChanged

 {

   public Window1()

   {

     InitializeComponent();    

   }

   private IEnumerable m_query = null;

   public IEnumerable OrdersQuery

   {

     get

     {

       if( m_query == null )

       {

         m_query = from orders in App.LinqDataContext.Orders

                   select orders;

       }

       return m_query;

     }

     set

     {

       m_query = value;

       this.OnPropertyChanged( new PropertyChangedEventArgs( "OrdersQuery" ) );

     }

   }

   private void ShipperSelectionChanged( object sender, SelectionChangedEventArgs e )

   {

     this.OrdersQuery = from orders in App.LinqDataContext.Orders

                 where orders.Shipper.CompanyName == ( ( Shipper )this.ShipperCombo.SelectedValue ).CompanyName

                 select orders;

   }

   private void SaveModifications( object sender, RoutedEventArgs e )

   {    

     App.LinqDataContext.SubmitChanges();

   }

   public event PropertyChangedEventHandler PropertyChanged;

   private void OnPropertyChanged( PropertyChangedEventArgs e )

   {

     if( this.PropertyChanged == null )

       return;

     this.PropertyChanged( this, e );

   }

 }

}