Json::Value root;   // will contains the root value after parsing.

Json::Reader reader;

bool parsingSuccessful = reader.parse( config_doc, root );

if ( !parsingSuccessful )

{

    // report to the user the failure and their locations in the document.

    std::cout  << "Failed to parse configuration\n"

               << reader.getFormattedErrorMessages();

    return;

}

// Get the value of the member of root named 'encoding', return 'UTF-8' if there is no

// such member.

std::string encoding = root.get("encoding", "UTF-8" ).asString();

// Get the value of the member of root named 'encoding', return a 'null' value if

// there is no such member.

const Json::Value plugins = root["plug-ins"];

for ( int index = 0; index < plugins.size(); ++index )  // Iterates over the sequence elements.

   loadPlugIn( plugins[index].asString() );

setIndentLength( root["indent"].get("length", 3).asInt() );

setIndentUseSpace( root["indent"].get("use_space", true).asBool() );

// ...

// At application shutdown to make the new configuration document:

// Since Json::Value has implicit constructor for all value types, it is not

// necessary to explicitly construct the Json::Value object:

root["encoding"] = getCurrentEncoding();

root["indent"]["length"] = getCurrentIndentLength();

root["indent"]["use_space"] = getCurrentIndentUseSpace();

Json::StyledWriter writer;

// Make a new JSON document for the configuration. Preserve original comments.

std::string outputConfig = writer.write( root );

// You can also use streams.  This will put the contents of any JSON

// stream at a particular sub-value, if you'd like.

std::cin >> root["subtree"];

// And you can write to a stream, using the StyledWriter automatically.

std::cout << root;