Bootstrap导航栏下拉框和汉堡菜单无法正常工作。

Question

Bootstrap导航栏下拉框和汉堡菜单无法正常工作。

javascriptjquerycsstwitter-bootstrapbootswatch

3

我正在使用Bootstrap创建导航栏，但是下拉菜单、汉堡包等都没有起作用。我的意思是当我点击它们时，它们不会展开。我之前已经使用过Bootstrap，并且从未遇到过这个问题。我使用了来自CDN的Bootswatch，为了安全起见，我还添加了Bootstrap CDN。但是经过测试，无论使用或不使用CDN，问题并未解决。

如果有用于解决此问题的ejs模板（本文中未显示），我也在使用它。我只是希望我的代码以任何形式都可以被测试，而不必使用ejs。

<html>
  <head>
    <meta charset=”UTF-8">
    <meta name=”viewport” content=”width=device-width, initial-scale=1">
    <!-- Katex latex renderer-->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.10.0-rc.1/dist/katex.min.css" integrity="sha384-D+9gmBxUQogRLqvARvNLmA9hS2x//eK1FhVb9PiU86gmcrBrJAQT8okdJ4LMp2uv" crossorigin="anonymous">
    <!-- The loading of KaTeX is deferred to speed up page rendering -->
    <script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.0-rc.1/dist/katex.min.js" integrity="sha384-483A6DwYfKeDa0Q52fJmxFXkcPCFfnXMoXblOkJ4JcA8zATN6Tm78UNL72AKk+0O" crossorigin="anonymous"></script>

    <!-- To automatically render math in text elements, include the auto-render extension: -->
    <script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.0-rc.1/dist/contrib/auto-render.min.js" integrity="sha384-yACMu8JWxKzSp/C1YV86pzGiQ/l1YUfE8oPuahJQxzehAjEt2GiQuy/BIvl9KyeF" crossorigin="anonymous" onload="renderMathInElement(document.body);"></script>

    <!-- Bootstrap -->
    <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">

    <!-- Bootstrap JavaScript -->
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" integrity="sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" crossorigin="anonymous"></script>

    <!-- Bootstrap JavaScript -->
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.bundle.min.js" integrity="sha384-pjaaA8dDz/5BgdFUPX6M/9SUZv4d12SUPF0axWc+VRZkx5xU3daN+lYb49+Ax+Tl" crossorigin="anonymous"></script>
    
    <script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script>

    <!-- Slate Bootswatch theme -->
    <link href="https://stackpath.bootstrapcdn.com/bootswatch/4.1.3/slate/bootstrap.min.css" rel="stylesheet" integrity="sha384-ywjdn7N8uoxzIfGl7jlEBlqw2BNicOSzZDgo7A2ffvbM24Ct9plRp7KwtaIqZ33j" crossorigin="anonymous">

    <title>title</title> 
  </head>
  <body>
  <nav class="navbar navbar-expand-lg navbar-dark bg-primary">
    <div class="container">
        <a class="navbar-brand" href="#">Navbar</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
          <span class="navbar-toggler-icon"></span>
        </button>
      <div class="collapse navbar-collapse" id="navbarNav">
        <ul class="navbar-nav mr-auto">
          <li class="nav-item">
            <a class="nav-link" href="/index.ejs">Home</a>
          </li>
          <li class="dropdown">
            <a class="dropdown-toggle" data-toggle="dropdown" href="#">Notes
            <span class="caret"></span></a>
            <ul class="dropdown-menu">
              <li><a href="#">Lambda Calculus</a></li>
              <li><a href="#">Languages and Machines</a></li>
              <li><a href="#">Logic Programming</a></li>
              <li><a href="#">Types and Programming languages</a></li>
            </ul>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/posts.ejs">Posts</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/about.ejs">About</a>
          </li>
        </ul>
      </div>
    </div>
  </nav>
  <div class="container">
    <div class="row bg-light">
      <div class="col-md-auto text-dark">
        <div id="notes">
         <p>PAGE CONTENT</p>
        </div>  
      </div>
    </div>
  </div>
<footer class="footer">
    <div class="container">
      <span class="text-muted">&copy; Me. All external content belongs to their respective owners.</span>
    </div>
  </footer>
  </body>
</html>

- K-Log

你在页面上先加载了Bootstrap JS，再加载jQuery - 这几乎肯定是为什么它不起作用的原因。(而且它应该在控制台上给你一个相应的消息。) - Robin Zigmond

1个回答

网页内容由stack overflow 提供, 点击上面的

可以查看英文原文，
原文链接

- Martin Fernandez · Accepted Answer

我建议您将脚本标签放在<body>标签结束之前。您可以查看此链接以了解为什么这样更好。

另外，您正在在引导链接之后加载jQuery。我进行了修改。

<html>
  <head>
    <meta charset=”UTF-8">
    <meta name=”viewport” content=”width=device-width, initial-scale=1">
    <script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script>
    <!-- Katex latex renderer-->
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@0.10.0-rc.1/dist/katex.min.css" integrity="sha384-D+9gmBxUQogRLqvARvNLmA9hS2x//eK1FhVb9PiU86gmcrBrJAQT8okdJ4LMp2uv" crossorigin="anonymous">
    <!-- The loading of KaTeX is deferred to speed up page rendering -->
    <script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.0-rc.1/dist/katex.min.js" integrity="sha384-483A6DwYfKeDa0Q52fJmxFXkcPCFfnXMoXblOkJ4JcA8zATN6Tm78UNL72AKk+0O" crossorigin="anonymous"></script>

    <!-- To automatically render math in text elements, include the auto-render extension: -->
    <script defer src="https://cdn.jsdelivr.net/npm/katex@0.10.0-rc.1/dist/contrib/auto-render.min.js" integrity="sha384-yACMu8JWxKzSp/C1YV86pzGiQ/l1YUfE8oPuahJQxzehAjEt2GiQuy/BIvl9KyeF" crossorigin="anonymous" onload="renderMathInElement(document.body);"></script>

    <!-- Bootstrap -->
    <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">

    <!-- Bootstrap JavaScript -->
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" integrity="sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" crossorigin="anonymous"></script>

    <!-- Bootstrap JavaScript -->
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.bundle.min.js" integrity="sha384-pjaaA8dDz/5BgdFUPX6M/9SUZv4d12SUPF0axWc+VRZkx5xU3daN+lYb49+Ax+Tl" crossorigin="anonymous"></script>

    

    <!-- Slate Bootswatch theme -->
    <link href="https://stackpath.bootstrapcdn.com/bootswatch/4.1.3/slate/bootstrap.min.css" rel="stylesheet" integrity="sha384-ywjdn7N8uoxzIfGl7jlEBlqw2BNicOSzZDgo7A2ffvbM24Ct9plRp7KwtaIqZ33j" crossorigin="anonymous">

    <title>title</title> 
  </head>
  <body>
  <nav class="navbar navbar-expand-lg navbar-dark bg-primary">
    <div class="container">
        <a class="navbar-brand" href="#">Navbar</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
          <span class="navbar-toggler-icon"></span>
        </button>
      <div class="collapse navbar-collapse" id="navbarNav">
        <ul class="navbar-nav mr-auto">
          <li class="nav-item">
            <a class="nav-link" href="/index.ejs">Home</a>
          </li>
          <li class="dropdown">
            <a class="dropdown-toggle" data-toggle="dropdown" href="#">Notes
            <span class="caret"></span></a>
            <ul class="dropdown-menu">
              <li><a href="#">Lambda Calculus</a></li>
              <li><a href="#">Languages and Machines</a></li>
              <li><a href="#">Logic Programming</a></li>
              <li><a href="#">Types and Programming languages</a></li>
            </ul>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/posts.ejs">Posts</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/about.ejs">About</a>
          </li>
        </ul>
      </div>
    </div>
  </nav>
  <div class="container">
    <div class="row bg-light">
      <div class="col-md-auto text-dark">
        <div id="notes">
         <p>PAGE CONTENT</p>
        </div>  
      </div>
    </div>
  </div>
<footer class="footer">
    <div class="container">
      <span class="text-muted">&copy; Me. All external content belongs to their respective owners.</span>
    </div>
  </footer>
  </body>
</html>