IVersion Interface

Defines the properties and methods that item version must implement. In addition to methods and properties provided by IDeltaVItem this interface also provides methods for getting version name, next version and previous version.

Usually you will implement IVersion interface for your file version objects together with IFile interface. While IFile interface is optional for file versions it may be useful if your DeltaV client application will request content of the file version. In this case ReadAsync(Stream, Int64, Int64), ContentLength and ContentType members of the IFile interface will be requested by the engine. Copying, moving, updating properties and content is not allowed for a version, your CopyToAsync(IItemCollection, String, Boolean, MultistatusException), MoveToAsync(IItemCollection, String, MultistatusException), UpdatePropertiesAsync(IListPropertyValue, IListPropertyName, MultistatusException) and WriteAsync(Stream, String, Int64, Int64) implementations must throw DavException with status NOT_ALLOWED.

Generally from your VersionName implementation you can return any string suitable for displaying to user as a version or the hierarchy item. This string must be unique among versions for this hierarchy item. Usually you will return “1”, “2”, etc or “3.1”, “3.4”, etc.

GetSuccessorAsync and GetPredecessorAsync methods of this interface return next and previous version for the item. The GetVersionableItemAsync method returns the hierarchy item (usually file) to which this version belongs.

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