Xceed.Wpf.Toolkit.DropDownButton.CanExecuteChanged C# (CSharp) Method

    private void CanExecuteChanged()
    {
      if( Command != null )
      {
        RoutedCommand command = Command as RoutedCommand;

        // If a RoutedCommand.
        if( command != null )
          IsEnabled = command.CanExecute( CommandParameter, CommandTarget ) ? true : false;
        // If a not RoutedCommand.
        else
          IsEnabled = Command.CanExecute( CommandParameter ) ? true : false;
      }
    }