memo property Null safety
read / write
(optional) Value of memo to attach to transaction, for hash this should be base64-encoded. Because a memo can be specified in the SEP-10 JWT for Shared Accounts, this field can be different than the value included in the SEP-10 JWT. For example, a client application could use the value passed for this parameter as a reference number used to match payments made to account.
Implementation
String? memo;