Delete record via RIA Services in Silverlight

I have a DataGrid in a Silverlight application. This application is using RIA Data Services. My code looks like the following:

<riaControls:DomainDataSource AutoLoad="True" 
  d:DesignData="{d:DesignInstance my1:Order, CreateList=true}" Height="0" 
  LoadedData="orderDomainDataSource_LoadedData" Name="orderDomainDataSource" 
  QueryName="GetOrdersQuery" Width="0">
  <riaControls:DomainDataSource.DomainContext>
     <my:OrderDomainContext />
  </riaControls:DomainDataSource.DomainContext>
</riaControls:DomainDataSource>
<sdk:DataGrid AutoGenerateColumns="True" Height="202" Name="ordersDataGrid" 
  HorizontalAlignment="Left" 
  ItemsSource="{Binding ElementName=orderDomainDataSource, Path=Data}">
</sdk:DataGrid>
<Button Content="De开发者_如何学Clete Order" Height="23" Name="deleteButton" 
  Width="90" Grid.Row="1" HorizontalAlignment="Left" Margin="102,8,12,0" 
  Click="deleteButton_Click" />

In my code-behind, I have

private void deleteButton_Click(object sender, System.Windows.RoutedEventArgs e)
{
  if (HtmlPage.Window.Confirm("Are you sure you want to delete this order?") == true)
  {
  }
}

My problem is, I can't figure out how to delete the record from my data source. How do I delete the record that is currently selected in my DataGrid?

Thank you

if (HtmlPage.Window.Confirm("Are you sure you want to delete this order?") == true)

{
DomainDataSource.DataView.Remove(DataGrid.SelectedItem);
DomainDataSource.SubmitChanges();
}

First of all, you can't define your own methods of Insert/Update/Delete -even observing the naming conventions - because the compiler generate a list of errors saying this is a redundant operation that already exists Second, in the client side if you write: DomainDataSource.DataView.Remove(DataGrid.SelectedItem); DomainDataSource.SubmitChanges() you get another error in execution time by saying this entity (DataGrid.SelectedItem) is not included in the entitySet Then What to do ? Why the CRUD Methods geneated can't be called directly ?