//Register button check if the event allrady sing into event
private void RegisterBtn_Click(object sender, RoutedEventArgs e)
{
if (registerPanel == null)
{
registerPanel = new RegisterPanel();
registerPanel.Closing += RegisterPanel_Closing;
}
registerPanel.Show();
}
private void RegisterPanel_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
registerPanel = null;
}
