A JSON parser in C++

Build Status


JSON++ is a light-weight JSON parser, writer and reader written in C++. JSON++ can also convert JSON documents into lossless XML documents.


If you've made substantial contribution, please add your link here.

Why another JSON parser?

Perhaps because web service clients are usually written in dynamic languages these days, none of the existing C++ JSON parsers fitted my needs very well, so I wrote one that I used in another project. My goals for JSON++ were:

Other contributors have sinced added more functionalities:

Compiler version

You need a modern C++ compiler. For older compilers, please try legacy branch.


Strict/permissive parsing

JSONxx can parse JSON documents both in strict or permissive mode.

When jsonxx::Settings::Parser is set to Strict, JSONxx parser will accept:

When jsonxx::Settings::Parser is set to Permissive, JSONxx parser will accept:

Default value is Permissive.

When jsonxx::Settings::UnquotedKeys is set to Enabled, JSONxx parser will accept:

Default value is Disabled.


JSONxx uses internally JSONXX_ASSERT(...) macro that works both in debug and release mode. Set jsonxx::Settings::Assertions value to Disabled to disable assertions.

Default value is Enabled.


The following snippets are from one of the unit tests. They are quite self-descriptive.

using namespace std;
using namespace jsonxx;

string teststr(
        "  \"foo\" : 1,"
        "  \"bar\" : false,"
        "  \"person\" : {\"name\" : \"GWB\", \"age\" : 60,},"
        "  \"data\": [\"abcd\", 42],"

// Parse string or stream
Object o;

// Validation. Checking for JSON types and values as well
assert(1 == o.get<Number>("foo"));
assert(o.get<Object>("person").get<Boolean>("old", false));
assert(o.get<Array>("data").get<Number>(1) == 42);
assert(o.get<Array>("data").get<String>(0) == "abcd");
assert(o.get<Array>("data").get<String>(2, "hello") == "hello");
cout << o.json() << endl;                     // JSON output
cout << o.xml(JSONx) << endl;                 // JSON to XML conversion (JSONx subtype)
cout << o.xml(JXML) << endl;                  // JSON to XML conversion (JXML subtype)
cout << o.xml(JXMLex) << endl;                // JSON to XML conversion (JXMLex subtype)
// Generate JSON document dynamically
using namespace std;
using namespace jsonxx;
Array a;
a << 123;
a << "hello world";
a << 3.1415;
a << 99.95f;
a << 'h';
a << Object("key", "value");
Object o;
o << "key1" << "value";
o << "key2" << 123;
o << "key3" << a;
cout << o.json() << endl;

To do

license MIT
project jsonxx
url github.com/hjiang/jsonxx
1 Version
version 1.0.1+1
repository pkg:cppget.org/stable
depends 0