Setting Control Numbers
By default the Interchange Control Number, Group Control Number and Transaction Set Control numbers are generated in the new 999 acknowledgement. These fields can also be overridden.
Example
Ack999Generator ack = new Ack999Generator();
// Override control numbers
ack.InterchangeControlNumber = 1234;
ack.GroupControlNumber = 5678;
ack.TransactionSetControlNumber = 9876;