The following HTML is an example to check if an option is selected in a select box.
<html>
<head>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.4.4.js"></script>
<script type="text/javascript">
$(document).ready(function() {
$("#select-box").change(function() {
if ($("#select-box option[value='3']").attr('selected')) {
alert('Ciao monde');
}
});
});
</script>
</head>
<body>
<select id="select-box">
<option>Select an option</option>
<option value="1">no alert</option>
<option value="2">no alert too</option>
<option value="3">alert</option>
</select>
</body>
</html>
Reference:
- Stack Overflow – Check if option is selected with jQuery, if not select a default
- JQuery – Select Box and Change Event
Eureka! 