JQuery 找出Checked的radio

<input type="radio" name="emailmode" id="emailmode1" value="1" /><label for="emailmode1">间隔告警</label>

<input type="radio" name="emailmode" id="emailmode2" value="2" /><label for="emailmode2">实时告警 </label>

<input type="radio" name="emailmode" id="emailmode3" value="3" /><label for="emailmode3">全都使用</label>

var emailactive = $("#emailactive1").attr("checked") == true ? "1" : "0";

var emailmode = "";

$("input[name='emailmode']:radio:checked").each(function () {

emailmode= $(this).val() ;

});