Return the raw byte[] for the vinary field. Note that you must also call GetBinaryLength() and GetBinaryOffset() to know which range of bytes in the returned array belong to this Field. About reuse: if you pass in the result byte[] and it is used, it is likely the underlying implementation will hold onto this byte[] and return it in future calls to BinaryValue() of GetBinaryValue(). So if you subsequently re-use the same byte[] elsewhere it will alter this Fieldable's value.
Fieldable Interface | Lucene.Net.Documents Namespace | Fieldable.GetBinaryValue Overload List