c++ protbuf object to bytes

gistfile1.txt

protocol::Note note = protocol::Note();
string name = "Buy vegetable";
string cafel = "-Apple\n-Pomodoro\n-Avocado";
note.set_name(name);
note.set_content(cafel);
note.set_id(1);
note.set_type(protocol::NoteType::BASIC);
Envelope envelope = createEnvelope(&note);

int size = envelope.ByteSize();
char* array = new char[size];
envelope.SerializeToArray(array, size);