我是Bootstrap的新手（通常是前端开发人员）。我正在尝试使Bootstrap4导航栏工作。我实质上已经从引导网站复制并粘贴了代码，但无法正常工作。
当我缩小页面时，菜单确实会折叠。但是，当我单击折叠菜单时，什么也没有发生。另外，在展开的菜单上，当我单击下拉菜单时什么也没有发生。
我已经验证了boostrap.min.js的路径正确。
我正在通过浏览器中的“ file：//”而不是从服务器加载此页面文件。我不知道这是否可能是一个问题，但我不这么认为。无论如何，这是代码：
<!DOCTYPE html>
<html>
<head>
<title>Title</title>
<meta charset="UTF-8">
<link rel="stylesheet" type="text/css" href="static/css/bootstrap.min.css" />
<script href="static/js/jquery-3.3.1.min.js"></script>
<script href="static/js/popper.min.js"></script>
<script href="static/js/bootstrap.min.js"></script>
</head>
<body>
<nav class="navbar navbar-expand-lg navbar-light bg-light">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown
</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
</ul>
</div>
</nav>
</body>
</html>
我确定这很简单（出于某种原因，我觉得javascript无法加载），但我无法弄清楚。有人看到明显的东西吗？
编辑：我还应该注意，我在控制台中没有看到任何Javascript错误，并且不确定自己是否检查正确，但是看起来好像没有为按钮注册事件监听器（所以单击该按钮时，什么都不会发生。
Edit2：我刚刚启动了一个快速的Web服务器来加载它。没有从服务器请求任何javascript文件。主要问题似乎与javascript文件的加载有关。路径是正确的。
已解决：问题是我在脚本标签中使用了href，而不是src。更改为src，一切正常。
答案 0 :(得分：1)
对于BootStrap4 Starter模板，请尝试以下代码。只要双击该文件，它将在任何地方运行。所有来源均来自CDN。
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<meta name="description" content="">
<meta name="author" content="">
<link rel="icon" href="../../../../favicon.ico">
<title>Starter Template for Bootstrap</title>
<!-- Bootstrap core CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
</head>
<body>
<nav class="navbar navbar-expand-md navbar-dark bg-dark fixed-top">
<a class="navbar-brand" href="#">Navbar</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarsExampleDefault" aria-controls="navbarsExampleDefault" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarsExampleDefault">
<ul class="navbar-nav mr-auto">
<li class="nav-item active">
<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Link</a>
</li>
<li class="nav-item">
<a class="nav-link disabled" href="#">Disabled</a>
</li>
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle" href="http://example.com" id="dropdown01" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Dropdown</a>
<div class="dropdown-menu" aria-labelledby="dropdown01">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
</ul>
<form class="form-inline my-2 my-lg-0">
<input class="form-control mr-sm-2" type="text" placeholder="Search" aria-label="Search">
<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
</form>
</div>
</nav>
<main role="main" class="container">
<div class="starter-template">
<h1>Bootstrap starter template</h1>
<p class="lead">Use this document as a way to quickly start any new project.<br> All you get is this text and a mostly barebones HTML document.</p>
</div>
</main><!-- /.container -->
<!-- Bootstrap core JavaScript
================================================== -->
<!-- Placed at the end of the document so the pages load faster -->
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
</body>
</html>
答案 1 :(得分：-1)
脚本标记的属性全部错误。我有href。应该是src。我修复了它，现在一切正常。