C++怎么实现对象序列化_C++数据持久化与对象序列化方法

class Person {
public:
    std::string name;
    int age;

    // 写入文件
    void save(std::ofstream& out) const {
        size_t len = name.size();
        out.write(reinterpret_cast<const char*>(&len), sizeof(len));
        out.write(name.c_str(), len);
        out.write(reinterpret_cast<const char*>(&age), sizeof(age));
    }

    // 从文件读取
    void load(std::ifstream& in) {
        size_t len;
        in.read(reinterpret_cast<char*>(&len), sizeof(len));
        name.resize(len);
        in.read(&name[0], len);
        in.read(reinterpret_cast<char*>(&age), sizeof(age));
    }
};

Person p{"Alice", 25};

// 序列化
std::ofstream out("data.bin", std::ios::binary);
p.save(out);
out.close();

// 反序列化
std::ifstream in("data.bin", std::ios::binary);
Person p2;
p2.load(in);
in.close();

#include <boost/serialization/string.hpp>
#include <boost/serialization/vector.hpp>
#include <boost/archive/text_oarchive.hpp>
#include <boost/archive/text_iarchive.hpp>

class Person {
    friend class boost::serialization::access;
    std::string name;
    int age;

    template<class Archive>
    void serialize(Archive& ar, const unsigned int version) {
        ar & name;
        ar & age;
    }
public:
    Person() {}
    Person(const std::string& n, int a) : name(n), age(a) {}
};

// 序列化到文本文件
{
    std::ofstream ofs("person.txt");
    boost::archive::text_oarchive oa(ofs);
    Person p("Bob", 30);
    oa << p;
}

// 反序列化
{
    std::ifstream ifs("person.txt");
    boost::archive::text_iarchive ia(ifs);
    Person p;
    ia >> p;
}

#include <nlohmann/json.hpp>

NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(Person, name, age)

// 序列化
nlohmann::json j = p;
std::string str = j.dump(); // 转字符串

// 反序列化
Person p2 = j.get<Person&gt();

message Person {
    string name = 1;
    int32 age = 2;
}