Question

When radio button 1 is selected print hello 1, when radio button 2 is selected print hello 2. How do I do this?

<form name="form" id="form">
First Class<input name="seat_class" id="a1" type="radio" value="First Class">
        Second Class        <input name="seat_class" type="radio" value="Standard Class"
        </form>

Answer 1

Try this:

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript">

$(document).ready(function () {
    $("#radio1, #radio2").change(function(event) {
        if($(this).is(':checked')) {
            alert($(this).data("text"));
        }
    });
});

</script>
<input type="radio" id="radio1" name="test" data-text="hello 1">
<input type="radio" id="radio2" name="test" data-text="hello 2">