Check whether specific radio button is checked

1.You don't need the @ prefix for attribute names any more:

http://api.jquery.com/category/selectors/attribute-selectors/:

Note: In jQuery 1.3 [@attr] style selectors were removed (they were previously deprecated in jQuery 1.2). Simply remove the ‘@’ symbol from your selectors in order to make them work again.

2.Your selector queries radio buttons by name, but that attribute is not defined in your HTML structure.

Your selector won't select the input field, and if it did it would return a jQuery object. Try this:

$('#test2').is(':checked'); 

I think you're using the wrong approach. You should set the value attribute of your input elements. Check the docs for .val() for examples of setting and returning the .val() of input elements.

ie.

<input type="radio" runat="server" name="testGroup" value="test2" />

return $('input:radio[name=testGroup]:checked').val() == 'test2';