OnUndoRedoChanged Method

protected virtual void OnUndoRedoChanged( 
   EventArgs e
)

'Declaration
 
Protected Overridable Sub OnUndoRedoChanged( _
   ByVal e As EventArgs _
) 

'Usage
 
Dim instance As AnnAutomation
Dim e As EventArgs
 
instance.OnUndoRedoChanged(e)

protected:
virtual void OnUndoRedoChanged( 
   EventArgs^ e
) 

Parameters

e

An System.EventArgs that contains the event data.

Raising an event invokes the event handler through a delegate. The OnUndoRedoChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class. Notes to Inheritors: When overriding OnUndoRedoChanged in a derived class, be sure to call the base class's OnUndoRedoChanged method so that registered delegates receive the event.

The UndoRedoChanged event will be fired when the undo/redo buffer changes. This gives the application a chance to update the user interface if needed.

The undo/redo buffer changes whenever an object inside the Container changes either by user interaction through the user interface or by code.

You can use the CanUndo property and the CanRedo property to determine whether this AnnAutomation can undo or redo an operation.

For C#/VB examples, refer to UndoRedoChanged.

Target Platforms

Reference

AnnAutomation Class
AnnAutomation Members