XML: Set Key name
The KeyName element contains a string value (in which white space is significant), which may be used by the signer to communicate a key identifier to the recipient. Typically, KeyName contains an identifier related to the key pair used to sign the message, but it may contain other protocol-related information that indirectly identifies a key pair. Common uses of KeyName include simple string names for keys, a key index, a distinguished name (DN), an email address, etc.
To add KeyName element to the EncryptedData element you need to use TElXMLEncryptor.KeyName property. When decrypting data using TElXMLDecryptor class you can use TElXMLDecryptor.KeyName property to read this value.