Re: [Boost-users] Boost.Serialization: Restoring objectstate(preventcreation of a new object)?

Subject: Re: [Boost-users] Boost.Serialization: Restoring objectstate(preventcreation of a new object)?
From: Robert Ramey (ramey_at_[hidden])
Date: 2010-08-31 12:31:38

ray_at_[hidden] wrote:
>> That's likely something else entirely.  We'd have to see more code.
> Forget my previous post, the exception was due to mixed up ofstream
> and ifstream...
>
> Just to resume - if I have a list of pointers to the objects (all
> derived from the same base class) and I'd like to serialize them
> through a reference, a code like this would be needed:
>
> // List of pointers
> A a;
> B b; // Derived from A
> C c; // Derived from C
> std::list<A*> list;
> list.push_back(&a);  // Base
> list.push_back(&b);  // Derived
> list.push_back(&c);  // Derived
> ...
> // Save
> std::ofstream ofs("c:/test.xml");
> boost::archive::xml_oarchive oa(ofs);
> BOOST_FOREACH(A* pA, list)
> {
>      if (dynamic_cast<B*>(pA))
>      {
>           B& b = *static_cast<B*>(pA);
>           oa & BOOST_SERIALIZATION_NVP(b);
>      }
>      else if (dynamic_cast<C*>(pA))
>      {
>           C& c = *pA;
>           BOOST_SERIALIZATION_NVP(c);
>      }
>      else
>      {
>           A& a = *pA;
>           BOOST_SERIALIZATION_NVP(a);
>      }
> }
>
>
> Am I right?

It's not absolutely clear what your object here is.
But the following would be equivalent to the above as far as I can tell - 
and a lot simpler

// Save
std::ofstream ofs("c:/test.xml");
boost::archive::xml_oarchive oa(ofs);
oa << list;

Robert Ramey