ImageEn, unit imageenproc




procedure UndoAt(Position: Integer; SaveToRedo: Boolean = False);


Replaces the current image with the one at Position in the Undo stack.

Parameter Description
Position Undo index to restore: 0 = last saved undo, 1 = second to last saved undo, 2... up to UndoCount - 1
AutoRedo Set to true for automatic redo support. Saves the current state (before undo) to the redo stack (i.e. calls SaveRedo) and removes this and prior entries from the Undo stack


Demo  Demos\ImageEditing\UndoRedo\UndoRedo.dpr


// Undo the last item (same as calling ImageEnView1.Proc.Undo)
ImageEnView1.Proc.UndoAt( 0, True );

// Undo All
ImageEnView1.Proc.UndoAt( ImageEnView1.Proc.UndoCount, True );

Compatibility Information

In v6.2.1 and older versions, AutoRedo would only assign the current state to the Redo List, and the undone item is not cleared. From v6.3.0, AutoRedo clears all undone entries and assigns them to the redo list.
To return to the older functionality, enable the IEUseLegacyUndoFunctionality define in

See Also

Public Property  CanUndo
Public Method  UndoRect
Public Method  Undo