1

我只是想学习 jQuery 和 Javascript。我开始了解概念，我觉得现实世界的问题是最好的学习方式。

我下载了 One Page Wonder Bootstrap 模板，我只是想找到导航的 outerHeight 并在警报中调用像素高度。

我试图用这个找到高度：

$('nav').outerHeight();

然后我尝试了几种方法来提醒这个高度：

alert(nav);
alert('nav');
alert($(nav));
alert($(nav));

我知道这可能很容易，但这不起作用。我需要使它成为一个功能吗？

这是 HTML，尽管我不确定是否需要它。它使用标准导航。

<!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="">

    <title>One Page Wonder - Start Bootstrap Template</title>

    <!-- Bootstrap core CSS -->
    <link href="vendor/bootstrap/css/bootstrap.min.css" rel="stylesheet">
    <script src="vendor/jquery/jquery.min.js"></script>

    <!-- Custom fonts for this template -->
    <link href="https://fonts.googleapis.com/css?family=Catamaran:100,200,300,400,500,600,700,800,900" rel="stylesheet">
    <link href="https://fonts.googleapis.com/css?family=Lato:100,100i,300,300i,400,400i,700,700i,900,900i" rel="stylesheet">

    <!-- Custom styles for this template -->
    <link href="css/one-page-wonder.min.css" rel="stylesheet">
    <script src="js/one-page-wonder.js"></script>
  </head>

  <body>

    <!-- Navigation -->
    <nav class="navbar navbar-expand-lg navbar-dark navbar-custom fixed-top">
      <div class="container">
        <a class="navbar-brand" href="#">Start Bootstrap</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarResponsive" aria-controls="navbarResponsive" aria-expanded="false" aria-label="Toggle navigation">
          <span class="navbar-toggler-icon"></span>
        </button>
        <div class="collapse navbar-collapse" id="navbarResponsive">
          <ul class="navbar-nav ml-auto">
            <li class="nav-item">
              <a class="nav-link" href="#">Sign Up</a>
            </li>
            <li class="nav-item">
              <a class="nav-link" href="#">Log In</a>
            </li>
          </ul>
        </div>
      </div>
    </nav>

    <header class="masthead text-center text-white">
      <div class="masthead-content">
        <div class="container">
          <h1 class="masthead-heading mb-0">One Page Wonder</h1>
          <h2 class="masthead-subheading mb-0">Will Rock Your Socks Off</h2>
          <a href="#" class="btn btn-primary btn-xl rounded-pill mt-5">Learn More</a>
        </div>
      </div>
      <div class="bg-circle-1 bg-circle"></div>
      <div class="bg-circle-2 bg-circle"></div>
      <div class="bg-circle-3 bg-circle"></div>
      <div class="bg-circle-4 bg-circle"></div>
    </header>

    <section>
      <div class="container">
        <div class="row align-items-center">
          <div class="col-lg-6 order-lg-2">
            <div class="p-5">
              <img class="img-fluid rounded-circle" src="img/01.jpg" alt="">
            </div>
          </div>
          <div class="col-lg-6 order-lg-1">
            <div class="p-5">
              <h2 class="display-4">For those about to rock...</h2>
              <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Quod aliquid, mollitia odio veniam sit iste esse assumenda amet aperiam exercitationem, ea animi blanditiis recusandae! Ratione voluptatum molestiae adipisci, beatae obcaecati.</p>
            </div>
          </div>
        </div>
      </div>
    </section>

    <section>
      <div class="container">
        <div class="row align-items-center">
          <div class="col-lg-6">
            <div class="p-5">
              <img class="img-fluid rounded-circle" src="img/02.jpg" alt="">
            </div>
          </div>
          <div class="col-lg-6">
            <div class="p-5">
              <h2 class="display-4">We salute you!</h2>
              <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Quod aliquid, mollitia odio veniam sit iste esse assumenda amet aperiam exercitationem, ea animi blanditiis recusandae! Ratione voluptatum molestiae adipisci, beatae obcaecati.</p>
            </div>
          </div>
        </div>
      </div>
    </section>

    <section>
      <div class="container">
        <div class="row align-items-center">
          <div class="col-lg-6 order-lg-2">
            <div class="p-5">
              <img class="img-fluid rounded-circle" src="img/03.jpg" alt="">
            </div>
          </div>
          <div class="col-lg-6 order-lg-1">
            <div class="p-5">
              <h2 class="display-4">Let there be rock!</h2>
              <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Quod aliquid, mollitia odio veniam sit iste esse assumenda amet aperiam exercitationem, ea animi blanditiis recusandae! Ratione voluptatum molestiae adipisci, beatae obcaecati.</p>
            </div>
          </div>
        </div>
      </div>
    </section>

    <!-- Footer -->
    <footer class="py-5 bg-black">
      <div class="container">
        <p class="m-0 text-center text-white small">Copyright &copy; Your Website 2018</p>
      </div>
      <!-- /.container -->
    </footer>

    <!-- Bootstrap core JavaScript -->

    <script src="vendor/bootstrap/js/bootstrap.bundle.min.js"></script>

  </body>

</html>
4

4 回答 4

2

将您分配$('nav').outerHeight()到一个变量中，然后尝试稍后使用它..在px变量的最后一个连接它来获得价值

var nav = $('nav').outerHeight();
console.log(nav + 'px');
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<nav class="navbar navbar-expand-lg navbar-dark bg-dark navbar-custom fixed-top">
  <div class="container">
    <a class="navbar-brand" href="#">Start Bootstrap</a>
    <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarResponsive" aria-controls="navbarResponsive" aria-expanded="false" aria-label="Toggle navigation"><span class="navbar-toggler-icon"></span></button>
    <div class="collapse navbar-collapse" id="navbarResponsive">
      <ul class="navbar-nav ml-auto">
        <li class="nav-item">
          <a class="nav-link" href="#">Sign Up</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Log In</a>
        </li>
      </ul>
    </div>
  </div>
</nav>

于 2018-02-17T04:27:35.207 回答
1 

console.log($('nav').outerHeight());
console.log($('nav').height());
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<nav>
  <ul>
    <li>hello</li>
    <li>hello</li>
    <li>hello</li>
  </ul>
</nav>

尝试使用控制台而不是警报，这是更好的方法并且易于调试。

于 2018-02-17T04:26:47.633 回答
1

您需要将此高度分配给某个变量以供以后使用：

let height = $("nav").outerHeight();
alert(height);
nav {
    height: 150px;
    width: 90%;
    background-color: cyan;
    padding: 10px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<nav></nav>

确保$("nav").outerHeight();在呈现 html 时调用 - 将 放在 html<script>的末尾或用window.onload = function() { ... };

于 2018-02-17T04:23:06.407 回答
0

我一直都做对了，但是我的<script>标签在标签上<head>而不是在</body>标签上方。一个菜鸟的错误。

我一直在使用 Wordpress 和 Gravity Forms 在需要调用的地方<head>，否则会弹出控制台错误。从我猜的基础开始。

谢谢基里尔指出。

于 2018-02-17T05:14:46.500 回答