c++ - 从 boost 序列化文件中读取会抛出异常

Question

我是 C++ 编码的新手。我正在尝试在 visual studio 上运行此代码以从 boost 序列化二进制文件中读取，当我尝试从中读取时，它会抛出异常。

#include <iostream>
#include <fstream>
#include <boost/archive/binary_oarchive.hpp>
#include <boost/archive/binary_iarchive.hpp>
#include <boost/serialization/binary_object.hpp>


using boost::serialization::make_binary_object;

enum class Example : uint32_t {
    A = 1,
    B = 2,
};

int main() {
    int data = 5;

    std::ofstream f("data.dat", std::ios::binary);
    boost::archive::binary_oarchive ar(f);
    ar << make_binary_object(&data, sizeof(data));

    uint32_t restored_info;
    std::ifstream Obj_ifstream("data.dat", std::ios::binary);
    boost::archive::binary_iarchive ip_archive(Obj_ifstream);
    ip_archive >> restored_info;

    std::cout << "Testing " << std::endl;
    system("PAUSE");
}

异常:

terminate called after throwing an instance of 'boost::archive::archive_exception'
what(): input stream error

Answer 1

在输出文件流关闭之前打开输入文件流(不能同时打开文件进行读写)。确保首先按照@rafix07 在他的评论中提到的那样关闭它，或者像这样封装代码块:

#include <iostream>
#include <fstream>
#include <boost/archive/binary_oarchive.hpp>
#include <boost/archive/binary_iarchive.hpp>
#include <boost/serialization/binary_object.hpp>


using boost::serialization::make_binary_object;

enum class Example : uint32_t {
    A = 1,
    B = 2,
};

int main() {
    int data = 5;

    {
        std::ofstream f("data.dat", std::ios::binary);
        boost::archive::binary_oarchive ar(f);
        ar << make_binary_object(&data, sizeof(data));
    }
    {
        uint32_t restored_info;
        std::ifstream Obj_ifstream("data.dat", std::ios::binary);
        boost::archive::binary_iarchive ip_archive(Obj_ifstream);
        ip_archive >> restored_info;
        std::cout << "restored ino " << restored_info << std::endl;
    }

    std::cout << "Testing " << std::endl;
    system("PAUSE");
}