| GrapeCity.Xaml.SpreadSheet.UI.UndoRedo Namespace > RowGroupHeaderExpandUndoAction Class : Undo Method | 
'Usage Dim instance As RowGroupHeaderExpandUndoAction Dim sender As Object Dim value As Boolean value = instance.Undo(sender)
true if undo is successful; otherwise, false.Target Platforms: Windows Server 2012, Windows RT