Bootstrap 导航栏开关未展开

Question

我想在移动 phone 中打开时使用 Bootstrap 导航栏展开网页。我在 html 文件中使用 Bootstrap 像这样的代码。

<html>
  <head>
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.2.1/dist/css/bootstrap.min.css" integrity="sha384-GJzZqFGwb1QTTN6wy59ffF1BuGJpLSa9DkKMp0DgiMDm4iYMj70gZWKYbI706tWS" crossorigin="anonymous">

    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/popper.js@1.14.6/dist/umd/popper.min.js" integrity="sha384-wHAiFfRlMFy6i5SRaxvfOCifBUQy1xHdJ/yoi7FRNXMRBu5WHdZYu1hA6ZOblgut" crossorigin="anonymous"></script>
    <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.2.1/dist/js/bootstrap.min.js" integrity="sha384-B0UglyR+jN6CkvvICOB2joaf5I4l3gm9GU6Hc1og6Ls7i6U/mkkaduKaBhlAXv9k" crossorigin="anonymous"></script>
  </head>
  <body>
      <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
          <div class="container-fluid">
              <li class="nav-item"><a class="navbar-brand" href="/"><i class="fa-solid fa-bolt"></i></a></li>
            <a class="navbar-brand" href="/">Center</a>
            <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-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 me-auto mb-2 mb-lg-0">
                <li class="nav-item">
                    <a class="nav-link" href="#">Hello</a>
                </li>                      
              </ul>
            </div>
          </div>
        </nav>
        <div class="container">
            <p>
            {% block content %}

            {% endblock %}
            </p>
        </div>
  </body>
</html>

当我点击这个按钮时，为什么它没有展开？

如何解决？

Answer 1

<html>
    <head>

      <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.2.1/dist/css/bootstrap.min.css" integrity="sha384-GJzZqFGwb1QTTN6wy59ffF1BuGJpLSa9DkKMp0DgiMDm4iYMj70gZWKYbI706tWS" crossorigin="anonymous">
      
      <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
      <script src="https://cdn.jsdelivr.net/npm/popper.js@1.14.6/dist/umd/popper.min.js" integrity="sha384-wHAiFfRlMFy6i5SRaxvfOCifBUQy1xHdJ/yoi7FRNXMRBu5WHdZYu1hA6ZOblgut" crossorigin="anonymous"></script>
      <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.2.1/dist/js/bootstrap.min.js" integrity="sha384-B0UglyR+jN6CkvvICOB2joaf5I4l3gm9GU6Hc1og6Ls7i6U/mkkaduKaBhlAXv9k" crossorigin="anonymous"></script>

    </head>
    
    <body>
      
        <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
            <div class="container-fluid">
                
                <li class="nav-item"><a class="navbar-brand" href="/"><i class="fa-solid fa-bolt"></i></a></li>
              <a class="navbar-brand" href="/">Center</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 me-auto mb-2 mb-lg-0">
                <li class="nav-item">
                    <a class="nav-link" href="#">Hello</a>
                </li>                      
                </ul>
              </div>
            </div>
          </nav>
          <div class="container">
              <p>
              abcd
              </p>
          </div>
    </body>
    
    </html>

试试这个。

 <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
        <div class="container-fluid">                
            <li class="nav-item"><a class="navbar-brand" href="/"><i class="fa-solid fa-bolt"></i></a></li>
          <a class="navbar-brand" href="/">Center</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 me-auto mb-2 mb-lg-0">
            <li class="nav-item">
                <a class="nav-link" href="#">Hello</a>
            </li>                      
            </ul>
          </div>
        </div>
      </nav>

Bootstrap 导航栏开关未展开

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