如何序列化共享/弱指针？
我有一个与 QSharedPointers 和 QWeakPointers 连接的复杂对象网络。有没有一种简单的方法可以使用 Boost.Serialization 保存/加载它们？到目前为止我有这个：
namespace boost {
namespace serialization {
template<class Archive, class T>
void save(Archive& ar, QSharedPointer<T> const& ptr, unsigned version) {
T* sharedPointer = ptr.data();
ar & BOOST_SERIALIZATION_NVP(sharedPointer);
}
template<class Archive, class T>
void load(Archive& ar, QSharedPointer<T>& ptr, unsigned version) {
T* sharedPointer = 0;
ar & BOOST_SERIALIZATION_NVP(sharedPointer);
ptr = QSharedPointer<T>(sharedPointer);
}
template<class Archive, class T>
void save(Archive& ar, QWeakPointer<T> const& ptr, unsigned version) {
T* weakPointer = ptr.toStrongRef().data();
ar & BOOST_SERIALIZATION_NVP(weakPointer);
}
template<class Archive, class T>
void load(Archive& ar, QWeakPointer<T>& ptr, unsigned version) {
T* weakPointer = 0;
ar & BOOST_SERIALIZATION_NVP(weakPointer);
ptr = QSharedPointer<T>(weakPointer);
}
}
}
这不起作用，因为共享指针总是从原始指针构造的，所以它们都认为引用计数是1。它还会立即释放弱指针。
经过一些努力，我可以将这些类转换为使用 boost::shared_ptr 和 boost::weak_ptr。这会有什么好处吗？
I have a complex network of objects connected with QSharedPointers and QWeakPointers. Is there a simple way to save/load them with Boost.Serialization? So far I have this:
namespace boost {
namespace serialization {
template<class Archive, class T>
void save(Archive& ar, QSharedPointer<T> const& ptr, unsigned version) {
T* sharedPointer = ptr.data();
ar & BOOST_SERIALIZATION_NVP(sharedPointer);
}
template<class Archive, class T>
void load(Archive& ar, QSharedPointer<T>& ptr, unsigned version) {
T* sharedPointer = 0;
ar & BOOST_SERIALIZATION_NVP(sharedPointer);
ptr = QSharedPointer<T>(sharedPointer);
}
template<class Archive, class T>
void save(Archive& ar, QWeakPointer<T> const& ptr, unsigned version) {
T* weakPointer = ptr.toStrongRef().data();
ar & BOOST_SERIALIZATION_NVP(weakPointer);
}
template<class Archive, class T>
void load(Archive& ar, QWeakPointer<T>& ptr, unsigned version) {
T* weakPointer = 0;
ar & BOOST_SERIALIZATION_NVP(weakPointer);
ptr = QSharedPointer<T>(weakPointer);
}
}
}
This is not working because the shared pointers are always constructed from raw pointers so they all think the reference count is 1. It also immediately frees weak pointers.
With some effort I can convert the classes to use boost::shared_ptr and boost::weak_ptr. Will that do any good?
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（1）
问题是你真正想通过序列化指针来实现什么目的？您的预期产出是多少？请注意，指针指向内存中的某个位置——多个指针可能指向内存中的同一位置。
序列化地址将不起作用。您不能只写下确切的内存地址，因为无法保证下一次运行的对象能够占用相同的空间（另一个程序可能已经保留了该位置）。
在我们有指针的每个地方序列化指向的对象不会工作：
想了一下，你可以尝试
boost::serialization的官方答案：The question is what do you really want to achieve by serializing pointers? What is your expected output? Note that pointers point to a place in memory -- several may point to the same place in memory.
Serializing the address won't work. You can't just write down the exact memory address, because there's no way to guarantee that objects on the next run will be able to take the same space (another program may have already reserved that place).
Serializing the pointed object in each place where we have a pointer wont work:
Now that you think about it, you can try the official answer of
boost::serialization: