var callback = function (status) {
    if (status === Strophe.Status.REGISTER) {
        // fill out the fields
        connection.register.fields.username = "juliet";
        connection.register.fields.password = "R0m30";
        // calling submit will continue the registration process
        connection.register.submit();
    } else if (status === Strophe.Status.REGISTERED) {
        console.log("registered!");
        // calling login will authenticate the registered JID.
        connection.authenticate();
    } else if (status === Strophe.Status.CONFLICT) {
        console.log("Contact already existed!");
    } else if (status === Strophe.Status.NOTACCEPTABLE) {
        console.log("Registration form not properly filled out.")
    } else if (status === Strophe.Status.REGIFAIL) {
        console.log("The Server does not support In-Band Registration")
    } else if (status === Strophe.Status.CONNECTED) {
        // do something after successful authentication
    } else {
        // Do other stuff
    }
};
connection.register.connect("example.com", callback, wait, hold);