private void btnDelete_Click(object sender, EventArgs e) { if(cardListsTreeView.SelNodes.Count < 1) return; if (MessageBox.Show("Are you sure you want to delete the selected group?", "Delete Selection?", MessageBoxButtons.YesNo) != DialogResult.Yes) { return; } LanguageData dataLayer = new LanguageData(); foreach (MWCommon.MWTreeNodeWrapper wrapper in cardListsTreeView.SelNodes.Values) { MyTreeNode node = wrapper.Node as MyTreeNode; switch (node.Type) { case MyTreeNodeType.CardList: dataLayer.DeleteCardList(node.ID); break; case MyTreeNodeType.Collection: dataLayer.DeleteCollection(node.ID); break; } } ReLoadNodes(); }