如何用jquery判断某组radio没有值

假如有多组radio具体数目不详，name值没有规律，如何用jquery判断某组radio没有选择？

<form id="vote">
    <div class="panel-body">
        <div class="subject" data-num="1">
            <div class="page-header">
                <h5>1.聪明的人到底要睡得多还是睡得少呢</h5>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="22" value="64">
                    <span class="options"><!-- (0). -->睡得多</span>
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="22" value="65">
                    <span class="options"><!-- (0). -->睡得少</span>
                </label>
            </div>
        </div>
        <div class="subject" data-num="2">
            <div class="page-header">
                <h5>2.最燃少年漫画！</h5>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="21" value="60">
                    <span class="options"><!-- (1). -->死神</span>
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="21" value="61">
                    <span class="options"><!-- (1). -->火影</span>
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="21" value="62">
                    <span class="options"><!-- (1). -->海贼王</span>
                </label>
            </div>
        </div>
        <div class="subject" data-num="3">
            <div class="page-header">
                <h5>3.能不能看到《城市猎人》完结？</h5>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="20" value="55">
                    <span class="options"><!-- (1). -->不能</span>
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="20" value="59">
                    <span class="options"><!-- (2). -->能</span>
                    
                </label>
            </div>
        </div>
        <div class="subject" data-num="4">
            <div class="page-header">
                <h5>4.一护应该娶谁？</h5>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="19" value="51">
                    <span class="options"><!-- (1). -->井上织姬</span>
                    
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="19" value="52">
                    <span class="options"><!-- (2). -->朽木露琪亚</span>
                    
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="19" value="53">
                    <span class="options"><!-- (3). -->朽木白哉</span>
                    
                </label>
            </div>
            <div class="radio">
                <label>
                    <input type="radio" name="19" value="54">
                    <span class="options"><!-- (4). -->阿东</span>
                    
                </label>
            </div>
        </div>
    </div>
    <div class="panel-footer">
        <a href="javascript:Wxvote();" type="submit" class="btn btn-default">投票</a>
    </div>
</form>

---

https://jsfiddle.net/b6wbL9mu/1/

$("a").on("click", e => {
    e.preventDefault();
    e.stopPropagation();
    $("div.subject").each(function() {
        let $div = $(this);
        if ($div.find(":radio:checked").length) {
            $div.css("background", "transparent");
        } else {
            $div.css("background", "lightpink");
        }
    });
});

注意：试验程序，改写了链接原来的行为

---

$('input').eq(1)[0].checked

---

你试试这个插件 jQuery Validate
简单例子看下面看下面

<input  type="radio" id="gender_male" value="m" name="gender" class="{required:true}" />
<input  type="radio" id="gender_female" value="f" name="gender"/>

---

谢谢邀请。你可以对每个组进行依次判断啊

$('div[data-num="2"]').each(function(){
    $(this).find('input[type="radio"]').attr('checked', 'true');
});