IRasterTransaction Interface

Provides access to members that provide undo support.

Members

	Name	Description
	Commit	Sends all pending changes to persistent storage.
	End	Commits changes and stops double buffering.
	Start	Starts double buffering edits for undo support.
	Undo	Reverses last N changes.
	UndoLevels	Maximum number of reversible operations.
	UndoLevels	Maximum number of reversible operations.

IRasterTransaction.Commit Method

Sends all pending changes to persistent storage.

Public Sub Commit ( _
)

public void Commit (
);

IRasterTransaction.End Method

Commits changes and stops double buffering.

Public Sub End ( _
)

public void End (
);

IRasterTransaction.Start Method

Starts double buffering edits for undo support.

Public Sub Start ( _
)

public void Start (
);

IRasterTransaction.Undo Method

Reverses last N changes.

Public Function Undo ( _
    ByVal N As Integer _
) As Integer

public int Undo (
    int N
);

IRasterTransaction.UndoLevels Property

Maximum number of reversible operations.

Public Property UndoLevels As Integer

public int UndoLevels {get; set;}

IRasterTransaction.UndoLevels Property

Maximum number of reversible operations.

Public Property UndoLevels As Integer

public int UndoLevels {get; set;}

Classes that implement IRasterTransaction

Classes	Description
RasterBand	A representation of a single band of a raster dataset on disk.

Remarks

This interface is supported on a file based RasterBand, not supported on a database RasterBand.

This interface allows you to setup and maintain a transaction stack that can revert from changes that have been made in memory before persisting these changes raster band. In this mechanism, a transaction is defined as either a write called on the dataset outside a double-buffered transaction or a set of writes contained within a single Start/End transaction block. The Start and End methods allow you to perform multiple writes that are managed by the undo stack as a single transaction.

To enable the transactioning mechanism, a band cache must first be created and then the undo level must be specified. To create the cache, call the AcquireCache method on the IRawPixels interface. After you are done editing, free the cache using the ReturnCache method.

This interface only works with raster in IMG, TIFF and GRID formats in ArcGIS 9.2