jQuery id 选择器正在选择所有元素

Question

我正在尝试 select 具有特定 ID（todoItems）的 ul，但页面上的所有 ul 都受此代码的影响。 特别是 ul 在我的导航栏中。 我也尝试通过 class 选择它们，但没有运气。 当我附加到 ul 时，我想不出一种方法来专门指定 select 的 li。 任何帮助表示赞赏。 请参阅下面的代码：

编辑* 这也是 css 。 我在一个快速应用程序中运行所有这些代码。 我在这个应用程序的一个页面上运行这个待办事项列表，它有自己的导航栏等。CSS/JS 等是使用 ejs 布局链接的。

 var todoItems = document.getElementById("todoItems"); $(todoItems).on("click", ".todoItem", function() { $(this).toggleClass("completed"); }); $(todoItems).on("click", "span.remove", function(event) { $(this).parent().fadeOut(300, function() { $(this).remove(); }); event.stopPropagation(); }); $("input[type='text']").on("keypress", function(event) { if (event.which === 13){ var todoText = $(this).val(); $(todoItems).append("<li class='todoItem'><span class = 'remove'><i class='fa fa-trash'></i> </span>" + todoText + "</li>"); } }); $(".fa-plus").on("click", () => { $("input[type='text']").fadeToggle(); });

 body { background-color: #43515f; }.siteBody { font-family: 'Roboto', sans-serif; background: #2980B9; /* fallback for old browsers */ background: -webkit-linear-gradient(to left, #FFFFFF, #6DD5FA, #2980B9); /* Chrome 10-25, Safari 5.1-6 */ background: linear-gradient(to left, #FFFFFF, #6DD5FA, #2980B9); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */ padding-top: 10px; padding-bottom: 10px; }.siteBody h1 { background-color: #2980b9; color: white; margin: 0; padding: 10px 20px; text-transform: uppercase; font-size: 24px; font-weight: normal; } input { font-size: 18px; background-color: #f7f7f7; width: 100%; padding: 13px 13px 13px 20px; color: #2980b9; border: 3px solid rgba(0, 0, 0, 0); } input:focus { background-color: white; border: 3px solid #2980b9; outline: none; }.siteBody ul { list-style: none; margin: 0; padding: 0; }.siteBody li { background-color: white; height: 40px; line-height: 40px; color: #666; }.siteBody li:nth-child(2n) { background-color: #f7f7f7; }.siteBody li:hover span { width: 40px; opacity: 1.0; }.siteBody span { background-color: #e74c3c; height: 40px; margin-right: 20px; text-align: center; color: white; width: 0; display: inline-block; transition: 0.2s linear; opacity: 0; }.fa-plus { float: right; }.completed { color: gray; text-decoration: line-through; } #container { background-color: #f7f7f7; box-shadow: : 0 0 3px rgba(0, 0, 0, 0.1); width: 360px; margin: 100px auto; }

 <nav id="mainNav" class="navbar navbar-expand-lg navbar-dark"> <div class="container"> <a class="navbar-brand" href="#">Trey Cooper</a> <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#mainNavbar" aria-controls="mainNavbar" aria-expanded="false" aria-label="Toggle navigation"> <span class="navbar-toggler-icon"></span> </button> <div class="collapse navbar-collapse" id="mainNavbar"> <ul class="navbar-nav mr-auto"> <li class="nav-item"> <a class="nav-link" href="/">Home <span class="sr-only">(current)</span></a> </li> <li class="nav-item"> <a class="nav-link" href="/posts">Projects</a> </li> <li class="nav-item"> <a class="nav-link" href="/posts/new">New Post</a> </li> </ul> <ul class="navbar-nav ml-auto"> <li class="nav-item"> <a class="nav-link" href="https://www.linkedin.com/in/trey-cooper-8a231a123/" target="_blank"><i class="fa fa-linkedin fa-lg white-text fa-2x"></i></a> </li> <li class="nav-item"> <a class="nav-link" href="https://github.com/cooper6101" target="_blank"><i class="fa fa-github fa-2x"></i></a> </li> </ul> </div> </div> </nav> <div class="container-fluid siteBody"> <div id="container"> <h1>TO-DO List <i class="fa fa-plus"></i></h1> <input type="text" name="addTodo" placeholder="Add New Todo"> <ul id="todoItems"> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Grocery Shop</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Get coding job</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Finish both Bootcamps</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Walk Fish</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Cook Dinner</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Book a flight</li> </ul> </div> </div>

Answer 1

由于您已经使用 jQuery，因此我更新了设置事件侦听器的方式并删除了选择元素的纯 js 方式。

 $("#todoItems >.todoItem").on("click", function() { $(this).toggleClass("completed"); }); $("#todoItems > span.remove").on("click", function(event) { $(this).parent().fadeOut(300, function() { $(this).remove(); }); event.stopPropagation(); }); $("input[type='text']").on("keypress", function(event) { if (event.which === 13) { var todoText = $(this).val(); $("#todoItems").append("<li class='todoItem'><span class = 'remove'><i class='fa fa-trash'></i> </span>" + todoText + "</li>"); } }); $(".fa-plus").on("click", () => { $("input[type='text']").fadeToggle(); });

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <nav id="mainNav" class="navbar navbar-expand-lg navbar-dark"> <div class="container"> <a class="navbar-brand" href="#">Trey Cooper</a> <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#mainNavbar" aria-controls="mainNavbar" aria-expanded="false" aria-label="Toggle navigation"> <span class="navbar-toggler-icon"></span> </button> <div class="collapse navbar-collapse" id="mainNavbar"> <ul class="navbar-nav mr-auto"> <li class="nav-item"> <a class="nav-link" href="/">Home <span class="sr-only">(current)</span></a> </li> <li class="nav-item"> <a class="nav-link" href="/posts">Projects</a> </li> <li class="nav-item"> <a class="nav-link" href="/posts/new">New Post</a> </li> </ul> <ul class="navbar-nav ml-auto"> <li class="nav-item"> <a class="nav-link" href="https://www.linkedin.com/in/trey-cooper-8a231a123/" target="_blank"><i class="fa fa-linkedin fa-lg white-text fa-2x"></i></a> </li> <li class="nav-item"> <a class="nav-link" href="https://github.com/cooper6101" target="_blank"><i class="fa fa-github fa-2x"></i></a> </li> </ul> </div> </div> </nav> <div class="container-fluid siteBody"> <div id="container"> <h1>TO-DO List <i class="fa fa-plus"></i></h1> <input type="text" name="addTodo" placeholder="Add New Todo"> <ul id="todoItems"> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Grocery Shop</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Get coding job</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Finish both Bootcamps</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Walk Fish</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Cook Dinner</li> <li class="todoItem"><span class="remove"><i class="fa fa-trash"></i></span> Book a flight</li> </ul> </div> </div>

Answer 2

请尝试以下代码：

var todoItems = document.getElementById("todoItems");

    $(document).on("click", "#todoItems .todoItem", function() {
        $(this).toggleClass("completed");
    });

    $(document).on("click", "#todoItems span.remove", function(event) {
        $(this).parent().fadeOut(300, function() {
            $(this).remove();
        });
        event.stopPropagation();
    });

    $("input[type='text']").on("keypress", function(event) {
        if (event.which === 13) {
            var todoText = $(this).val();
            $(todoItems).append("<li class='todoItem'><span class = 'remove'><i class='fa fa-trash'></i> </span>" + todoText + "</li>");
        }
    });

    $(".fa-plus").on("click", () => {
        $("input[type='text']").fadeToggle();
    });