// radio 값 가져오기
$('input:radio[name="is_radio"]:checked').val()

// radio 선택 하기
$("input:radio[name='is_radio']:input[value="+item.is_radio+"]").attr("checked", true);

//선택 index 가져오기
var radioIdx = $(":radio[name='is_radio']").index($(":radio[name='is_radio']:checked"));

//change event
$("input[name='is_radio']").change(function() {

});

//asp.net MVC, 부스트스트랩, booststrap
<div class="btn-group" data-toggle="buttons">
@{  
 int i = 0;
 foreach (var xItem in (List<oncd_radio>)ViewBag.Radio)
{
     if (i == 0)
     {
        @new HtmlString("<label class= btn btn-default btn-primary active >"))
     }
     else
     {
        @(new HtmlString("<label class= btn btn-default btn-primary >"))
     }
     <input type="radio" id="is_radio_@(i.ToString())" name="is_radio" value="@(xItem.is_radio)"/>@(xItem.is_radio_name)
     @(new HtmlString("</label>"))
     i++;
 }
}
</div>