Question

我对那些有点奇怪的东西感到难过。我正在修改一个包含js和html的html文件中的代码，直到我按照我想要的方式工作，然后将其复制并粘贴到链接到JS页面的php文件中。麻烦的是，在php页面中我收到错误消息无法识别的表达式：select [name = gateHeight] option：selected。如果有人能解释我搞砸了什么，我会非常感激！这是带有JS和HTML的html文件：

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <title></title>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js"></script>

    <script type="text/javascript">
        $(document).ready(function() {
            $('#btnAdd').click(function() {
                var num     = $('.clonedInput').length; // how many "duplicatable" input fields we currently have
                var newNum  = new Number(num + 1);      // the numeric ID of the new input field being added

                // create the new element via clone(), and manipulate it's ID using newNum value
                var newElem = $('#input' + num).clone().attr('id', 'input' + newNum);

                // manipulate the name/id values of the input inside the new element
                newElem.children($("select[name=gateHeight] option: selected")).attr('id', 'gateHeight' + newNum).attr('name', 'gateHeight' + newNum);
                //newElem.children('input[type=text]:first').attr('id', 'name' + newNum).attr('name', 'name' + newNum);
                newElem.children('input[type=checkbox]:first').attr('id', 'chk' + newNum).attr('name', 'chk' + newNum);

                // insert the new element after the last "duplicatable" input field
                $('#input' + num).after(newElem);

                // enable the "remove" button
                //$('#btnDel').attr('disabled','');
                $('#btnDel').removeAttr('disabled');

                // business rule: you can only add 5 names
                if (newNum == 5)
                    $('#btnAdd').attr('disabled','disabled');
            });

            $('#btnDel').click(function() {
                var num = $('.clonedInput').length; // how many "duplicatable" input fields we currently have
                $('#input' + num).remove();     // remove the last element

                // enable the "add" button
                //$('#btnAdd').attr('disabled','');
                $('#btnAdd').removeAttr('disabled');

                // if only one element remains, disable the "remove" button
                if (num-1 == 1)
                    $('#btnDel').attr('disabled','disabled');
            });

            $('#btnDel').attr('disabled','disabled');
        });
    </script>
</head>

<body>

<form id="myForm">
    <div id="input1" style="margin-bottom:4px;" class="clonedInput">
       <!-- <input type="text" name="name1" id="name1" /> -->
        <select name="gateHeight" id="gateHeight">
                            <option value="select">Select Gate Height</option>
                            <option value="4fg">4 Ft. Gate</option>
                            <option value="6fg">6 Ft. Gate</option>
                            <option value="8fg">8 Ft. Gate</option>
        </select> 
        Include Spring Pool Latch: <input type="checkbox" name="chk1" id="chk1" />
    </div>

    <div>
        <input type="button" id="btnAdd" value="add another name" />
        <input type="button" id="btnDel" value="remove name" />
    </div>
</form>
</body>

这是另一个文件的JS和HTML： JS：

//Dynamic Gate Input Fields
    $('#btnAdd').click(function() {
                var num     = $('.clonedInput').length; // how many "duplicatable" input fields we currently have
                var newNum  = new Number(num + 1);      // the numeric ID of the new input field being added

                // create the new element via clone(), and manipulate it's ID using newNum value
                var newElem = $('#input' + num).clone().attr('id', 'input' + newNum);

                // manipulate the name/id values of the input inside the new element
                newElem.children($("select[name=gateHeight] option: selected")).attr('id', 'gateHeight' + newNum).attr('name', 'gateHeight' + newNum);
                //newElem.children('input[type=text]:first').attr('id', 'name' + newNum).attr('name', 'name' + newNum);
                newElem.children('input[type=checkbox]:first').attr('id', 'chk' + newNum).attr('name', 'chk' + newNum);

                // insert the new element after the last "duplicatable" input field
                $('#input' + num).after(newElem);

                // enable the "remove" button
                //$('#btnDel').attr('disabled','');
                $('#btnDel').removeAttr('disabled');

                // business rule: you can only add 5 names
                if (newNum == 5)
                    $('#btnAdd').attr('disabled','disabled');
            });

            $('#btnDel').click(function() {
                var num = $('.clonedInput').length; // how many "duplicatable" input fields we currently have
                $('#input' + num).remove();     // remove the last element

                // enable the "add" button
                //$('#btnAdd').attr('disabled','');
                $('#btnAdd').removeAttr('disabled');

                // if only one element remains, disable the "remove" button
                if (num-1 == 1)
                    $('#btnDel').attr('disabled','disabled');
            });

            $('#btnDel').attr('disabled','disabled');

HTML：

<div id="input1" style="margin-bottom:4px;" class="clonedInput">
                        <select name="gateHeight" id="gateHeight">
                                <option value="select">Select Gate Height</option>
                                <option value="4fg">4 Ft. Gate</option>
                                <option value="6fg">6 Ft. Gate</option>
                                <option value="8fg">8 Ft. Gate</option>
                        </select> 
                        Include Spring Pool Latch: <input type="checkbox" name="chk1" id="chk1" />
                    </div>

            <div>
                <input type="button" id="btnAdd" value="Add Another Gate" />
                <input type="button" id="btnDel" value="Remove Gate" />
            </div>

Answer 1

您缺少文档就绪包装函数，在元素存在之前调用您的代码，因此失败。

Answer 2

你需要摆脱option: selected中冒号之后的空格。只需将其更改为option:selected。

Answer 3

尝试

$("select[name=gateHeight] option :selected")

:selected是正确的: selected（无空格）

OR

$("select[name=gateHeight] option").filter(":selected")

这将有效

Answer 4

首先您应该使用updated version的{{1}}，例如 jquery-1.9 或更高版本。

第二次您应该使用jquery代替 newElem.children("select[name=gateHeight]") 像

newElem.children($("select[name=gateHeight] option: selected"))

Demo

JS在一个地方工作但不在另一个地方

4 个答案: