How do you serialize an object in C++?

Question

I have a small hierarchy of objects that I need to serialize and transmit via a socket connection. I need to both serialize the object, then deserialize it based on what ty

Answer 1

In some cases, when dealing with simple types, you can do:

object o;
socket.write(&o, sizeof(o));

That's ok as a proof-of-concept or first-draft, so other members of your team can keep working on other parts.

But sooner or later, usually sooner, this will get you hurt!

You run into issues with:

• Virtual pointer tables will be corrupted.
• Pointers (to data/members/functions) will be corrupted.
• Differences in padding/alignment on different machines.
• Big/Little-Endian byte ordering issues.
• Variations in the implementation of float/double.

(Plus you need to know what you are unpacking into on the receiving side.)

You can improve upon this by developing your own marshalling/unmarshalling methods for every class. (Ideally virtual, so they can be extended in subclasses.) A few simple macros will let you to write out different basic types quite quickly in a big/little-endian-neutral order.

But that sort of grunt work is much better, and more easily, handled via boost's serialization library.