private void EditEnumerationValue()
 {
     using (EditEnumerationValue dialog = new EditEnumerationValue((EnumerationValueMapping)enumerationValuesListBox.SelectedItem))
     {
         dialog.ShowDialog(this);
     }
 }
        private void addEnumerationValueButton_Click(object sender, EventArgs e)
        {
            using (EditEnumerationValue dialog = new EditEnumerationValue())
            {
                if (dialog.ShowDialog(this) == DialogResult.OK)
                    AddEnumerationValue(dialog.EnumerationValueMapping);

                PropertyChanged(sender, e);
            }
        }