Controller is firing but I can't get the $_GET

Hooray!I finally got the message from the client back to the server with POST! Thank you! Back on the client, you have:

xhr.onload = function () { //response will go here
// Request finished. Do processing here.
};

question: 1) once I build the response on the server, how do I send it back to the client? 2) I realize the onload will fire, but how do I get access to the buffer response on the client?

proof that an old dog can learn new tricks