setExtraData

ExtraData is a parametrized property that allows the client to store additional data within the signature object after capture.

For example, if a signature is being manually validated, the system may find it convenient to store the result in the signature itself, rather than as an independent data item.

Each ExtraData item must be given an identifying key name under a string value named key and an associate value string named value. There can be only one value for each key and once written the key cannot be modified or removed. All ExtraData key pairs are protected by the signature object integrity hash.

Parameters
Key: name of the extra data, if it already exists it will be overridden.
Value: value of the extra data.

Return values
None