jquery常见操作总结

var value= $("input:radio[name='per'][checked]").val();

$("input[name='testradio']:eq(1)").attr("checked","checked");//

eq(1)表示第二个

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang='zh-CN' xml:lang='zh-CN' xmlns='http://www.w3.org/1999/xhtml'>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
    
    <script type="text/javascript" src="http://www.oschina.net/js/2012/jquery-1.7.1.min.js"></script>
   <script>
    $(function(){
        $("#btnGetRadioValue").click(function(){
            var value=$("input:radio[name='per'][checked]").val();
            alert(value);
        });
        $("#btnSetRadioValue").click(function(){
            var value=$("input:radio[name='per'][checked]").val();
            value=value*1-1;
            if(value==0)
                value=1;
            else
                value=0;
            $("input:radio[name='per']:eq("+value+")").attr("checked","checked");
        });
        $("#btnGetSelectValue").click(function(){
            var value=$("#ddl").val();
            alert(value);
        });
         
        $("#btnSetSelectValue").click(function(){
            var value=$("#ddl option:eq(2)").attr("selected","selected");
        });
    });
   </script>
  </head>
<body>
 1<input type="radio" name="per" value="1"/>
 2<input type="radio" name="per" value="2"/>
 <input type="button" value="GetRadioValue" id="btnGetRadioValue"/>
 <input type="button" value="SetRadioValue" id="btnSetRadioValue"/><br/>
 <select id="ddl">
    <option value="-1">--</option>
    <option value="1">1</option>
    <option value="2">2</option>
 </select>
 <input type="button" value="GetSelectValue" id="btnGetSelectValue"/>
  <input type="button" value="SetSelectValue" id="btnSetSelectValue"/>
</body>
</html>