Question

这是代码，其字面意思是仅使用标准CDN和文档中导航栏的精确副本，并且当其最小化时，单击汉堡包菜单没有任何作用？我可能只是傻了，是的，我很困惑

<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
    <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://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
    <title>Index</title>
</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="#" tabindex="-1" aria-disabled="true">Disabled</a>
            </li>
          </ul>
          <form class="form-inline my-2 my-lg-0">
            <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
            <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
          </form>
        </div>
      </nav>
</body>
</html>```

Answer 1

如果您在引导程序之前添加jquery和popper js文件，则效果很好，因为这两者都需要

如果您使用的是经过编译的JavaScript，请不要忘记在之前添加CDN版本的jQuery和Popper.js 。

<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" 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://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>

    <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="#" tabindex="-1" aria-disabled="true">Disabled</a>
            </li>
          </ul>
          <form class="form-inline my-2 my-lg-0">
            <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
            <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
          </form>
        </div>
      </nav>

Answer 2

这是引导程序错误

util.js:55 Uncaught TypeError: Cannot read property 'fn' of undefined
    at util.js:55
    at bootstrap.min.js:6
    at bootstrap.min.js:6

function setTransitionEndSupport() {
  $.fn.emulateTransitionEnd = transitionEndEmulator
  $.event.special[Util.TRANSITION_END] = getSpecialTransitionEndEvent()
}

我建议使用其他版本。

[{https://cdnjs.com/libraries/twitter-bootstrap][Bootstrap CDN]

以后，右键单击页面，然后选择检查。然后，在Chrome开发者工具中，您可以选择控制台标签以搜索任何错误或警告。

直接来自文档的Bootstrap导航栏不起作用

2 个答案: