I am not able to get the data from node server to c++ client using socket io

Node server

socket.broadcast.emit('JogJointButton', data)
data = {
            name: Suneeth,
            age: 27
       }

now im accepting this data from server in c++ client. right now my code looks like this.

        sio::client io;
        io.set_open_listener([&]() {
            std::string nickName = "asdad";
            io.socket()->emit("key", nickName);
            io.socket()->on("JogJointButton", [&](sio::event& ev)
                    {
                       //Here how do i get the **data** from server
                    });
        });
        io.connect("http://localhost:8081/");

How do i accept that data inside c++. i tried ev.get_messages() but im getting some reference.