[Rise]

<input id="checkbox_jax" type="checkbox" />
<input id="but" type="image" src="images/site/enter_button.png" alt="Enter" />
<div id="res_log"></div>
<script>
document.getElementById('but').onclick = function() {
	$.post("/auth.php", { check: +document.getElementById('checkbox_jax').checked }, function(data) { 
		document.getElementById('res_log').innerHTML = data;
	});
	return false;
}
</script>

if (isset($_POST['check'])) echo ($_POST['check']) ? 'on' : 'off';