private void UpdateItem(IndentedComboBox.Item item, IndentedComboBox.Item selectedItem, ref int index)
{
foreach (IndentedComboBox.Item current in item.GetChildren())
{
if (current == selectedItem)
{
index = this.comboBox.Items.Count;
}
this.comboBox.Items.Add(current);
this.UpdateItem(current, selectedItem, ref index);
}
}