This is the code
HTML
<select id="selectChange" name="selectChange">
<option value='1' >One</option>
<option value='2' >Two</option>
<option value='3' >Three</option>
<option value='4' >Four</option>
</select>
JQuery
$('#selectChange').change(function(){
alert( $(this).val());
});
I created a JSFiddle for JQuery on select change event. This is the link to that. As you can see, it is not working.
Then I got one JSFidle working link for JQuery on select change event form SO answer.(Don't remeber where.)
Then I updated the code to the one I already wrote in the previous link. This is the updated JSFiddle link . And it is working fine. If ypu remove the /29/ from this second URL, you can see the old JSFidle link.
You can see both the code are same. But why the first one is not working? Whenever I try to create a new JSFiddle for JQuery, I'm not able to perform it and I need to check for any already existing one and update it.
You need to select a version of jQuery in the first drop down below the heading Frameworks & Extensions.
At the moment it's set to No library (Pure JS). This means jQuery is not available to use.