Thanks for your explanation. That's really weird if the length depends on actual integer values! Seems I need to reorganize my serialization logic.
在 2016年8月19日星期五 UTC-4下午2:20:01，Feng Xiao写道： > > > On Fri, Aug 19, 2016 at 10:50 AM, <[email protected] <javascript:>> > wrote: > >> The question is: >> >> My message looks like: >> >> Message data >> { >> optional uint32 object_id = 1; >> optional uint32 next_id = 2; >> } >> >> I might define my message object like below: >> >> data; >> size_t msg_size_before = data.ByteSize(); >> >> uint32 id = CreateNewId(); >> uint32 next_id = GetCurNextId(); >> >> data.set_object_id(id); >> data.set_next_id(next_id); >> >> size_t msg_size_after = data.ByteSize(); >> >> >> Since I defined only integers in my message type, can I always assume >> assert "msg_size_before == msg_size_after" ???? >> > No, you can't. > > In protobuf an uint32 field type uses variable-length encoding. That means > its byte size depends on the actual value of the field. If you set a new > value, the byte size can change as well. > > >> -- >> You received this message because you are subscribed to the Google Groups >> "Protocol Buffers" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at https://groups.google.com/group/protobuf. >> For more options, visit https://groups.google.com/d/optout. >> > > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/d/optout.
