I'm newbie to C++. What's the easiest way to serialize and deserialize data of type std::Map
using boost
. I've found some examples with using PropertyTree
but they are obscure for me.
Note that property_tree
interprets the keys as paths, e.g. putting the pair "a.b"="z" will create an {"a":{"b":"z"}} JSON, not an {"a.b":"z"}. Otherwise, using property_tree
is trivial. Here is a little example.
#include <sstream>
#include <map>
#include <boost/property_tree/ptree.hpp>
#include <boost/property_tree/json_parser.hpp>
using boost::property_tree::ptree;
using boost::property_tree::read_json;
using boost::property_tree::write_json;
void example() {
// Write json.
ptree pt;
pt.put ("foo", "bar");
std::ostringstream buf;
write_json (buf, pt, false);
std::string json = buf.str(); // {"foo":"bar"}
// Read json.
ptree pt2;
std::istringstream is (json);
read_json (is, pt2);
std::string foo = pt2.get<std::string> ("foo");
}
std::string map2json (const std::map<std::string, std::string>& map) {
ptree pt;
for (auto& entry: map)
pt.put (entry.first, entry.second);
std::ostringstream buf;
write_json (buf, pt, false);
return buf.str();
}