C++ rapidjson converts nested map to nested json

Life is short, I use rapidjson

Look at the code:

#include <iostream>
#include <map>
//  Please download the open source one yourself rapidjson
#include "rapidjson/prettywriter.h"
#include "rapidjson/rapidjson.h"
#include "rapidjson/document.h"
#include "rapidjson/stringbuffer.h"
#include "rapidjson/writer.h"
#include "rapidjson/memorystream.h"
using namespace std;
using rapidjson::Document;
using rapidjson::StringBuffer;
using rapidjson::Writer;
using namespace rapidjson;
string formJson(const map<string, int> &mInt, const map<string, string> &mString,
     const string &strChild, const map<string, int> &mChildInt, const map<string, string> &mChildString)
{
 Document document;
  Document::AllocatorType& allocator = document.GetAllocator(); 
  Value root(kObjectType);
  Value child(kObjectType);
  Value key(kStringType); 
  Value value(kStringType); 
 //  The current level 
 for(map<string, int>::const_iterator it = mInt.begin(); it != mInt.end(); ++it) 
 {
 key.SetString(it->first.c_str(), allocator); 
   root.AddMember(key, it->second, allocator);
 }
 for(map<string, string>::const_iterator it = mString.begin(); it != mString.end(); ++it)
 {
 key.SetString(it->first.c_str(), allocator); 
   value.SetString(it->second.c_str(), allocator); 
   root.AddMember(key, value, allocator);
 }
 //  The child level 
 if(!strChild.empty())
 {
 for(map<string, int>::const_iterator it = mChildInt.begin(); it != mChildInt.end(); ++it) 
 {
  key.SetString(it->first.c_str(), allocator); 
   child.AddMember(key, it->second, allocator);
 }
 for(map<string, string>::const_iterator it = mChildString.begin(); it != mChildString.end(); ++it)
 {
  key.SetString(it->first.c_str(), allocator); 
   value.SetString(it->second.c_str(), allocator); 
   child.AddMember(key, value, allocator);
 }
 key.SetString(strChild.c_str(), allocator); 
 root.AddMember(key, child, allocator);
 }
  StringBuffer buffer; 
  Writer<StringBuffer> writer(buffer); 
  root.Accept(writer); 
  return buffer.GetString(); 
}
int main(int argc, char *argv[])
{
 map<string, int> mInt;
 mInt["code"] = 0;
 mInt["score"] = 80;
 map<string, string> mString;
 mString["name"] = "taoge";
 mString["place"] = "shenzhen";
 string strChild = "childNode";
 map<string, int> mChildInt;
 mChildInt["code"] = 0;
 mChildInt["score"] = 100;
 map<string, string> mChildString;
 mChildString["name"] = "taogeChild";
 mChildString["place"] = "shenzhen";
 string strJson = formJson(mInt, mString, 
            strChild, mChildInt, mChildString);
 cout << strJson << endl;
 return 0;
}

Results:

{"code":0,"score":80,"name":"taoge","place":"shenzhen","childNode":{"code":0,"score":100,"name":"taogeChild","place":"shenzhen"}}

In addition, if you only want to have the current sector, you can do it like this (C++ default parameter) :

#include <iostream>
#include <map>
//  Please download the open source one yourself rapidjson
#include "rapidjson/prettywriter.h"
#include "rapidjson/rapidjson.h"
#include "rapidjson/document.h"
#include "rapidjson/stringbuffer.h"
#include "rapidjson/writer.h"
#include "rapidjson/memorystream.h"
using namespace std;
using rapidjson::Document;
using rapidjson::StringBuffer;
using rapidjson::Writer;
using namespace rapidjson;
map<string, int> g_mChildInt;
map<string, string> g_mChildString;
string formJson(const map<string, int> &mInt, const map<string, string> &mString,
     const string &strChild="", const map<string, int> &mChildInt=g_mChildInt, const map<string, string> &mChildString=g_mChildString)
{
 Document document;
  Document::AllocatorType& allocator = document.GetAllocator(); 
  Value root(kObjectType);
  Value child(kObjectType);
  Value key(kStringType); 
  Value value(kStringType); 
 //  The current level 
 for(map<string, int>::const_iterator it = mInt.begin(); it != mInt.end(); ++it) 
 {
 key.SetString(it->first.c_str(), allocator); 
   root.AddMember(key, it->second, allocator);
 }
 for(map<string, string>::const_iterator it = mString.begin(); it != mString.end(); ++it)
 {
 key.SetString(it->first.c_str(), allocator); 
   value.SetString(it->second.c_str(), allocator); 
   root.AddMember(key, value, allocator);
 }
 //  The child level 
 if(!strChild.empty())
 {
 for(map<string, int>::const_iterator it = mChildInt.begin(); it != mChildInt.end(); ++it) 
 {
  key.SetString(it->first.c_str(), allocator); 
   child.AddMember(key, it->second, allocator);
 }
 for(map<string, string>::const_iterator it = mChildString.begin(); it != mChildString.end(); ++it)
 {
  key.SetString(it->first.c_str(), allocator); 
   value.SetString(it->second.c_str(), allocator); 
   child.AddMember(key, value, allocator);
 }
 key.SetString(strChild.c_str(), allocator); 
 root.AddMember(key, child, allocator);
 }
  StringBuffer buffer; 
  Writer<StringBuffer> writer(buffer); 
  root.Accept(writer); 
  return buffer.GetString(); 
}
int main(int argc, char *argv[])
{
 map<string, int> mInt;
 mInt["code"] = 0;
 mInt["score"] = 80;
 map<string, string> mString;
 mString["name"] = "taoge";
 mString["place"] = "shenzhen";
 string strJson = formJson(mInt, mString);
 cout << strJson << endl;
 return 0;
}

Results:

{"code":0,"score":80,"name":"taoge","place":"shenzhen"}

In fact, the formJson function above can be further extended.

conclusion