FrameworkElement.BringIntoView Method (System.Windows)

    Private Sub browserFrame_FragmentNavigation(ByVal sender As Object, ByVal e As FragmentNavigationEventArgs)
        Dim element As FrameworkElement = TryCast(LogicalTreeHelper.FindLogicalNode(DirectCast(DirectCast(e.Navigator, ContentControl).Content, DependencyObject), e.Fragment), FrameworkElement)
        If (element Is Nothing) Then
            ' Redirect to error page
            ' Note - You can't navigate from within a FragmentNavigation event handler,
            '        hence creation of an async dispatcher work item
            Dim callback As New DispatcherOperationCallback(AddressOf Me.FragmentNotFoundNavigationRedirect)
            Me.Dispatcher.BeginInvoke(DispatcherPriority.Normal, callback, Nothing)
        End If
        e.Handled = True
    End Sub

    Function FragmentNotFoundNavigationRedirect(ByVal unused As Object) As Object
        Me.browserFrame.Navigate(New Uri("FragmentNotFoundPage.xaml", UriKind.Relative))
        Return Nothing
    End Function

void browserFrame_FragmentNavigation(object sender, FragmentNavigationEventArgs e)
{
    object content = ((ContentControl)e.Navigator).Content;
    FrameworkElement fragmentElement = LogicalTreeHelper.FindLogicalNode((DependencyObject)content, e.Fragment) as FrameworkElement;
    if (fragmentElement == null)
    {
        // Redirect to error page
        // Note - You can't navigate from within a FragmentNavigation event handler,
        //        hence creation of an async dispatcher work item
        this.Dispatcher.BeginInvoke(
            DispatcherPriority.Send,
            (DispatcherOperationCallback) delegate(object unused) 
            {
                this.browserFrame.Navigate(new Uri("FragmentNotFoundPage.xaml", UriKind.Relative));
                return null;
            },
            null);
        e.Handled = true;
    }
}