[TYPO3-mvc] be module ajax - json encode model

[Stephen Bungert]

I have a be module that gets table records. At the moment I can get a record 
by findByUid, and if I do something like:

$ajaxObj->addContent('Import', json_encode('title' => $item->getTitle()));

I see the title of my record in the response object.

I then tried doing this:

$ajaxObj->addContent('Import', json_encode($item));

This didn't work. How do I json encode all the properties of my record?

Thanks for any help

Stephen.