C++ convert JSON to XML

Question

I am trying to find a way to convert JSON string to XML document. For this we have evaluated PICOJSON to parse JSON and Pugixml to generate the XML document.

I know this is way easy in .Net and JAVA. My JSON is dynamic and based on the dynamic JSON I have to convert to XML.

I need some starting help on how to achieve this. Below code is sample to Parse JSON

#include <iostream>
#include "include/picojson.h";
#include "include/pugixml.hpp";
using namespace std;

int main() {
   
    const char* json =
        "{\"menu\": {"
        "\"id\": \"f\","
        "\"popup\": {"
        "  \"menuitem\": ["
        "    {\"v\": \"0\"},"
        "    {\"v\": \"1\"},"
        "    {\"v\": \"2\"}"
        "   ]"
        "  }"
        "}"
        "}";
    picojson::value v;
    std::string err;
    const char* json_end = picojson::parse(v, json, json + strlen(json), &err);
    
}

I think the initial approach would be to covert JSON String to JSON object(Not sure how to do that) and then recursively construct XML Will the below code convert JSON string to Object ?

picojson::parse(v, json, json + strlen(json), &err);
    if (!err.empty()) {
        std::cerr << err << std::endl;
    }

Can someone guide me with initial code on how to do it, how to construct XML from JSON ?

Answer 1

If you're willing to use RapidJSON instead, you can make a SAX parser based on this example and map each JSON read event to an homologous XML write operation.

Hint: this probably means keeping a pugi::xml_node currentNode somewhere to keep track of the current node being worked on.

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Edit
It seems POCO has SAX-like handlers after all, so you won't even need RapidJSON for this.
And if you want to minimize your dependencies, you can also use POCO.XML instead of pugixml.