JQuery获得radio选中值

$('input:radio[name="couponPageVO.isPublic"]:checked').val();

<s:radio id="isPublic" name="couponPageVO.isPublic" list="%{@cn.tootoo.boss.entities.card.thcard.states.YesOrNoEnum@list()}" value="0" listKey="c" listValue="s" theme="simple" onclick="showLotSn()"/>

注：查找id="isPublic"无效，取不得数值