Question

jquery如何判断radio元素是否为空

我这里有3个表单radio元素，我想用jquery做一下判断，
如果用户没有选择这个东西的话就弹出个对话框提醒他选一下

这是html代码

<p class="pjc">
<span>好评<br /><input type="radio" name="check" value="1" /> <img src="./images/pjimg1.jpg" /></span>
<span>中评<br /><input type="radio" name="check" value="2" /> <img src="./images/pjimg2.jpg" /> </span>
<span>差评<br /><input name="check" type="radio" value="3" /> <img src="./images/pjimg3.jpg" /></span>
</p>

劳烦各位了....

Answer 1

<p class="pjc">
            <span>好评
                <br />
                <input type="radio" name="check" value="1"  />
                <img src="./images/pjimg1.jpg" /></span>
            <span>中评
                <br />
                <input type="radio" name="check" value="2" />
                <img src="./images/pjimg2.jpg" /> </span>
            <span>差评
                <br />
                <input name="check" type="radio" value="3" />
                <img src="./images/pjimg3.jpg" /></span>
</p>
<input type="submit" id="submit" />

$(function() {
				$("#submit").click(function() {
					if (!$(".pjc input[name=check]").is(":checked")) { 
					alert("error");
					return false;
					} else {
					alert("ok");
					}
				})
			})

Answer 2

if(!$(':radio[name=check]:checked').length) {
    alert('请选择评价');
}