C ++使用for循环将对象列表序列化为XML

Question

我有一个对象列表，并想将其序列化为xml。我的目标是：

struct PingLogDto
{
    int PingLogID;
    int HardwareHostID;
    std::string PingLogRoundtripTime;
};

在这里我将我的列表如下：

vector<PingLogDto> pingLogList;

for(int i = 0; i < 3; i++)
{
    PingLogDto pingLog;
    pingLog.HardwareHostID = 1;
    pingLog.PingLogRoundtripTime = std::to_string(i);

    pingLogList.push_back(pingLog);
}

我将此列表发送到将序列化我的对象的方法：

RequestHandler().SendPingServerLog(pingLogList);

我的方法是：

void RequestHandler::SendPingServerLog(vector<PingLogDto> pingLogList)
{
    std::string xml = "";

    for (auto &pingLog : pingLogList) 
    {
        std::string docStringValue;
        PingLogDto pingLogDto;
        PingLogDtoXml::Saver saver;

        pugi::xml_document _doc;

        saver(_doc.root(), "PingLog", pingLog);

        std::stringstream ss;
        _doc.save(ss);
        docStringValue =  ss.str();
        xml += docStringValue;
    }

    std::cout<<"xml: "<<xml<<std::endl;    
}

在这种方法中;我使用pugixml库进行序列化。由于非反射语言c ++，我不得不这样做来序列化我的对象。这是我的老问题：How to change or delete tags in boost serialization?和我的对象标题如下：

struct PingLogDtoXml {
    struct Saver {
        template <typename T>
        void operator()(pugi::xml_node parent, std::string const& name, T const& value) const {
            auto node = named_child(parent, name);
            node.text().set(to_xml(value));
        }

        template <typename C>
        void operator()(pugi::xml_node parent, std::string const& name, std::string const& item_name, C const& container) const {
            auto list = named_child(parent, name);

            for (auto& item : container)
                operator()(list, item_name, item);
        }

        void operator()(pugi::xml_node parent, std::string const& name, PingLogDto const& o) const {
            auto dto = named_child(parent, name);
            operator()(dto, "PingLogID", o.PingLogID);
            operator()(dto, "HardwareHostID", o.HardwareHostID);
            operator()(dto, "PingLogRoundtripTime", o.PingLogRoundtripTime);
        }

    private:
        template <typename T> static T const& to_xml(T const& v) { return v; }
        static char const* to_xml(std::string const& v) { return v.c_str(); }

        pugi::xml_node named_child(pugi::xml_node parent, std::string const& name) const {
            auto child = parent.append_child();
            child.set_name(name.c_str());
            return child;
        }
    };

    struct Loader {
        void operator()(pugi::xml_node parent, std::string const& name, std::string& value) const {
            auto node = parent.first_element_by_path(name.c_str());
            value = node.text().as_string();
        }
        void operator()(pugi::xml_node parent, std::string const& name, int& value) const {
            auto node = parent.first_element_by_path(name.c_str());
            value = node.text().as_int();
        }

        template <typename C>
        void operator()(pugi::xml_node parent, std::string const& name, std::string const& item_name, C& container) const {
            auto list = parent.first_element_by_path(name.c_str());

            for (auto& node : list) {
                if (node.type() != pugi::xml_node_type::node_element) {
                    std::cerr << "Warning: unexpected child node type ignored
";
                    continue;
                }
                if (node.name() != item_name) {
                    std::cerr << "Warning: unexpected child node ignored (" << node.name() << ")
";
                    continue;
                }

                container.emplace_back();
                operator()(node, container.back());
            }
        }

        void operator()(pugi::xml_node dto, PingLogDto& o) const {
            operator()(dto, "PingLogID", o.PingLogID);
            operator()(dto, "HardwareHostID", o.HardwareHostID);
            operator()(dto, "PingLogRoundtripTime", o.PingLogRoundtripTime);            
        }

        void operator()(pugi::xml_node parent, std::string const& name, PingLogDto& o) const {
            operator()(parent.first_element_by_path(name.c_str()), o);
        }
    };
};

此结构可以成功将对象序列化为xml。只是为了清楚，这是我的例子：

PingLogDto pingLog;
pingLog.HardwareHostID = 1;
pingLog.PingLogRoundtripTime = "45";

如果我序列化这个pingLog对象：saver（_doc.root（），“PingLog”，pingLog）;

打印将是这样的：

<?xml version="1.0"?>
<PingLog>
    <PingLogID>0</PingLogID>
    <HardwareHostID>1</HardwareHostID>
    <PingLogRoundtripTime>45</PingLogRoundtripTime>
</PingLog>

我的问题是，当我序列化一个数组时，我得到了每个对象的xml标签。这里有一个xml打印示例：

<?xml version="1.0"?>
<PingLog>
    <PingLogID>0</PingLogID>
    <HardwareHostID>1</HardwareHostID>
    <PingLogRoundtripTime>0</PingLogRoundtripTime>
    <PingLogDate>123</PingLogDate>
</PingLog>
<?xml version="1.0"?>
<PingLog>
    <PingLogID>0</PingLogID>
    <HardwareHostID>1</HardwareHostID>
    <PingLogRoundtripTime>1</PingLogRoundtripTime>
</PingLog>
<?xml version="1.0"?>
<PingLog>
    <PingLogID>0</PingLogID>
    <HardwareHostID>1</HardwareHostID>
    <PingLogRoundtripTime>2</PingLogRoundtripTime>
</PingLog>

我怎么能解决这个问题，我的错是什么？

Answer 1

另一答案