javascript Jquery .addClass 和 .removeClass 不工作？
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Jquery .addClass and .removeClass Not Working?
提问by mesut
I wrote a code that clicking an item displays a context menu like div to enabling user to cut and paste a list item, I added disabled class to buttons in div that are related to paste operation. but when something selected I want to remove the class 'disable' to enable paste buttons. the code is as below:
我写了一个代码，点击一个项目会显示一个上下文菜单，比如 div 以允许用户剪切和粘贴列表项，我向 div 中与粘贴操作相关的按钮添加了禁用类。but when something selected I want to remove the class 'disable' to enable paste buttons. 代码如下：
html:
html：
<div id="contextMenu" class="text-center" style="display: none; z-index: 1001; width: 242px;box-shadow:#D3D3D3 0px 0px 10px 4px; background-color: #FDFFC7; padding: 15px;">
<a class="btn btn-primary" style="margin: 3px 6px 3px 0px;" href="#" id="cut"><i class="fa fa-cut fa-lg"></i> Kes</a>
<div class="btn-group" style="margin: 3px 0px 3px 6px;">
<button type="button" class="btn btn-success disabled" id="InsertInto" title="Kesti?ini kategoriyi se?ti?iniz kategorinin i?ine yap??t?r?r."><i class="fa fa-paste fa-lg"></i> Yap??t?r</button>
<button type="button" class="btn btn-success dropdown-toggle disabled" data-toggle="dropdown"><span class="caret"></span></button>
<ul class="dropdown-menu" role="menu">
<li><a href="#" title="Se?ti?iniz kategorinin üstüne ekler" id="AddAbove"><i class="fa fa-level-up fa-lg"></i> üstüne Ekle</a></li>
<li><a href="#" title="Se?ti?iniz kategorinin Alt?na ekler" id="AddBelow"><i class="fa fa-level-down fa-lg"></i> Alt?na Ekle</a></li>
</ul>
</div>
JS:
JS：
$(document).on('click', '.ContextMenu', function () {
event.preventDefault();
var anySelected = $('.selected').length;
if (anySelected > 0) {
$("button", "#contextManu").removeClass('disabled');
}
var widgetPosition = $('#contextMenu').parent().offset();
$('#contextMenu').css('position', 'absolute');
var currentPosition = $(this).offset();
var contextLeft = (currentPosition.left) - $('#contextMenu').width() - widgetPosition.left - 10;
var contextTop = (currentPosition.top + 80) - widgetPosition.top;
$('#contextMenu').css('left', contextLeft);
$('#contextMenu').css('top', contextTop);
$('#contextMenu').slideDown(300);
$selectedListItem = $(this).parents('div.categoryItemContainer').parent();
});
I Trace code using google chrome browser, $("button", "#contextManu") founds two button in the contextMenu div but not changes it.
我使用 google chrome 浏览器跟踪代码，$("button", "#contextManu") 在 contextMenu div 中找到了两个按钮，但没有更改它。
回答by Code Maverick
You have a typo in your selector at this line:
您在这一行的选择器中有一个错字：
$("button", "#contextManu").removeClass('disabled');
#contextManuneeds to have the achanged to an elike so:
#contextManu需要a更改为e这样的：
$("button", "#contextMenu").removeClass('disabled');
回答by Damon
You could also use toggleClass. I recently found that gem out myself.
你也可以使用toggleClass。我最近自己发现了那颗宝石。
$('button', '#contextMenu').toggleClass('disabled');
From the docs:Add or remove one or more classes from each element in the set of matched elements, depending on either the class's presence or the value of the switch argument.
来自文档：根据类的存在或 switch 参数的值，从匹配元素集中的每个元素中添加或删除一个或多个类。
So, you don't even need to add "disabled" to your element(s) to begin with.
因此，您甚至不需要在开始时向元素添加“禁用”。
