JQ的is()

 is()：根据选择器、元素或jQuery对象来检测匹配元素集合， 如果这些元素中至少有一个元素匹配给定的参数，则返回true。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1"/>
    <title>Title</title>
    <script src="../jquery-3.1.0.min.js"></script>
    <style>
        input {display: none}
        .radioTxt {
            display: inline-block;
            width: 100px;
            height: 40px;
            text-align: center;
            line-height: 40px;
        }
        input[type='radio']:checked + .radioTxt {
            background: #FCA700;
        }
    </style>
</head>
<body>
    <label class="item1">
        <input type="radio" value="单选框1" name="radio"/>
        <span class="radioTxt">单选框1</span>
    </label>
    <label class="item2">
        <input type="radio" value="单选框2" name="radio"/>
        <span class="radioTxt">单选框2</span>
    </label>
    <label class="item3">
        <input type="radio" value="单选框3" name="radio"/>
        <span class="radioTxt">单选框3</span>
    </label>
    <p></p>
    <script>
        /*
        is()：根据选择器、元素或jQuery对象来检测匹配元素集合，
        如果这些元素中至少有一个元素匹配给定的参数，则返回true
        */
        $("input[type='radio']").click(function (index, item) {
            var flag = $(this).is(":checked");
            var parentIsLabel = $(this).parent().is("label");
            var txt = $(this).val();
            if (flag) {
                console.log("txt: " + txt);
                console.log("input parent is label: " + parentIsLabel)
            }
        });
    </script>
</body>
</html>

posted @ 2021-07-07 11:22  し7709  阅读(187)  评论(0)    收藏  举报