private void HandleUpClick(object sender, RoutedEventArgs routedEventArgs)
 {
     if (AcceptUpDownOnNull && Number == null)
     {
         _number.ToMinimum();
     }
     else
     {
         _number.Increase();
     }
     TakeNumber();
     _textBox.Text = _number.ToString();
     if (NumberSelectionBehavior == NumberBoxSelection.OnFocusAndUpDown || NumberSelectionBehavior == NumberBoxSelection.OnUpDown)
     {
         SelectAll();
     }
 }