Imports Infragistics.Win.UltraWinTree
Private Sub ultraTree1_BeforeCollapse(ByVal sender As Object, ByVal e As Infragistics.Win.UltraWinTree.CancelableNodeEventArgs) Handles ultraTree1.BeforeCollapse
Dim sb As New System.Text.StringBuilder()
sb.Append("Node: ")
sb.Append(e.TreeNode.Key)
sb.Append(" is about to be collapsed.")
Debug.WriteLine(sb.ToString())
' 注: この操作が以下のコード行によってキャンセルできます
'e.Cancel = True
End Sub