private void xButtonSave_Click(object sender, RoutedEventArgs e)
{
SaveFileDialog dialog = new SaveFileDialog();
dialog.AddExtension = true;
dialog.DefaultExt = ".bn";
dialog.FileOk += delegate(object s2, CancelEventArgs e2)
{
string fileName = dialog.FileName;
App.Current.MainWindow.RequestSaveBayesianNetwork(fileName);
};
dialog.ShowDialog();
}