jQuery选择器--:selected和:checked

:selected

概述

匹配所有选中的option元素

<!DOCTYPE html>
<html>

    <head>
        <meta charset="UTF-8">
        <title></title>
        <script type="text/javascript" src="js/jquery-3.1.1.min.js"></script>
        <script type="text/javascript">
            $(document).ready(function() {
                $("button").click(function() {
                    $("div").html($("select option:selected").text());
                })
            })
        </script>
    </head>

    <body>
        <select>
            <option>Java</option>
            <option>C#</option>
            <option>HTML</option>
        </select>
        <button>点击</button>
        <br />
        <div></div>
    </body>

</html>

:checked

概述

匹配所有选中的被选中元素(复选框、单选框等，select中的option)，对于select元素来说，获取选中推荐使用 :selected

<!DOCTYPE html>
<html>

    <head>
        <meta charset="UTF-8">
        <title></title>
        <script type="text/javascript" src="js/jquery-3.1.1.min.js"></script>
        <script type="text/javascript">
            $(document).ready(function() {
                $("button").click(function() {
                    $("div").html($("input:checked").eq(1).val());
                });
            })
        </script>
    </head>

    <body>
        <input type="checkbox" name="language" value="Java" /><span>Java</span><br />
        <input type="checkbox" name="language" value="C#" /><span>C#</span><br />
        <input type="checkbox" name="language" value="HTML" /><span>HTML</span><br />
        <button>点击</button>
        <div></div>
    </body>

</html>