为什么 jquery 悬停在 jsfiddle 中有效，但在我的 html 布局中无效？

Question

我正在制作一个带有下拉登录框的网页。当鼠标悬停在导航菜单中的列表项上时，登录框应向下滑动 jquery hover.

登录表单隐藏在 css 中并显示：none 直到将鼠标悬停在登录 link 上。

这在 jsfiddle 中完美运行：

/**
 * @author Øystein Jacobsen
 * @date 24.03.2015
 */

$("#login").hover(function() {
 $("#login-form").slideToggle();
});

body {
 background: gray url("../img/bg-default.png") no-repeat;
 background-size: cover;
 font-size: 85%;
 font-family: Arial, 'Lucicda Sans Unicode';
 line-height: 1.5;
 text-align: left;
 margin: 0 auto;
 width: 70%;
 clear: both;
}

a {
 color: #474E69; /*#CF5C3F;*/
 text-decoration: none;
}

a:link, a:visited {
 color: #474E69; /*#CF5C3F;*/
}

a:hover, a:active {
 color: white;
 background-color: #474E69; /*#CF5C3F;*/
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
}


/* HTML4 FALLBACK */
header, section, footer, aside, nav, main, article, figure {
    display: block; 
}


/* HEADER */
.main-header img {
 width: 100%;
 height: auto;
}


/* NAVIGATION */
.navigation {
 background-color: #666;
 height: 40px;
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
 margin-bottom: 2%;
 padding-right: 40px;
}

.navigation ul {
 list-style: none;
 margin: 0 auto;
}

.navigation ul.main-nav li {
 float: left;
 display: inline;
}

.navigation ul.ext-nav li {
 float: right;
 display: inline;
}

.navigation ul li a {
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
}

.navigation a:link, .navigation a:visited {
 color: white;
 display: inline-block;
 padding: 10px 20px;
 height: 20px
}

.navigation a:hover, .navigation a:active, .navigation .active a:link, .navigation .active a:visited {
 background-color: #474E69; /*#CF5C3F;*/
 text-shadow: none;
}


/* CONTENT */
.main-content {
 width: 70%;
 float: left;
 line-height: 25px;
}

.main-content article {
 background-color: white;
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
 padding: 2% 5%;
 margin-bottom: 3%;
}

.main-content .post-info {
 font-style: italic;
 font-size: 80%;
 color: #999;
}



/* SIDEBAR */
.sidebar {
 width: 28%;
 float: left;
 margin-left: 2%;
}

.sidebar article {
 background-color: white;
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
 padding: 2% 5%;
 margin-bottom: 8%;
}


/* FOOTER */
.main-footer {
 width: 100%;
 height: 40px;
 float: left;
 clear: both;
 margin-bottom: 2%;
 text-align: center;
 color: white;
 background-color: #666;
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
}

.main-footer p {
 margin: 10px auto;
}

/* login.css */
#login-form  {
 position: absolute;
 right: 15%;
    display: none;
    float: right;
    clear: both;
    background-color: #666;
    padding: 0 2% 2% 2%;
 border-radius: 5px;
 -moz-border-radius: 5px;
 -webkit-border-radius: 5px;
}

#login-form .text {
 width: 100%;
    float: right;
    margin-bottom: 2%;
}

#login-form .submit {
    float: right;
}

/* mobile.css */
/* SCREENS LOWER THAN 750xp NO LOGIN */
@media only screen and (min-width: 625px) and (max-width: 750px) { 
 .navigation ul.ext-nav {
  display: none;
 }
 
 .navigation {
        padding-right: 0;
 }
}


/* SCREENS BETWEEN 150px & 600px */
@media only screen and (max-width: 625px) {
 body {
  width: 90%;
  font-size: 95%;
 }
 
 .navigation {
  height: 200px;
        padding-right: 0;
 }
 
 .navigation ul {
  padding-left: 0;
 }
 
 .navigation ul li {
  width: 100%;
  text-align: center;
 }
 
 .navigation a:link, .navigation a:visited {
  padding: 10px 25px;
  height: 20px;
  display: block;
 }
    
    #login-form  {
        width: 86%;
        right: 5%;
    }
  
 .main-content {
  width: 100%;
 }
 
 .main-content article {
  margin-bottom: 2%;
 }
 
 .post-info {
  display: none;
 }
 
 .sidebar {
  width: 100%;
  margin-left: 0;
 }
 
 .sidebar article {
  padding: 2% 3%;
  margin-bottom: 2%;
 }
}

<!DOCTYPE html>
<html>
 <head>
  <title>iRock.no</title>
  
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  
  <link rel="stylesheet" type="text/css" href="css/main.css" />
  <link rel="stylesheet" type="text/css" href="css/mobile.css" />
  <link rel="stylesheet" type="text/css" href="css/login.css" />
  
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
  <script src="script/login.js"></script>
  <!-- IE9 AND LESS HTML5 SUPPORT -->
  <!--[if lt IE 9]>
   <script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
  <![endif]-->
 </head>

 <body>
 
  <!-- HEADER -->
  <header class="main-header">
   <img alt="Header" src="img/hd-default_freemono.png">
  </header>
  
  
  <!-- NAVIGATION -->
  <nav class="navigation">
   <ul class="main-nav">
    <li class="active"><a href="#">Home</a></li>
    <li><a href="#">Workspace</a></li>
    <li><a href="#">About</a></li>
    <li><a href="#">Contact</a></li>
   </ul>
   
   <ul class="ext-nav">
    <li id="login">
     <a  href="#" margin-right="40px">login</a>
     <form id="login-form" action="script/login.php" method="post">
               <p><input class="text" type="text" name="username" placeholder="username" /></p>
               <p><input class="text" type="password" name="password" placeholder="password" /></p>
               <p><input class="submit" type="submit" value="submit" /></p>
     </form>
    </li>
    
   </ul>
  </nav>
  
  
  <!-- CONTENT -->
  <section class="main-content">
   <!-- TODO: program article generator -->
   <article>
    <header class="article-header">
     <h1><a href="#">First Article</a></h1>
    </header>
    
    <footer>
     <p class="post-info">by iRock</p>
    </footer>
    
    <content>
     <p>Lorem ipsum dolor sit amet, erant tempor fuisset ea nec. 
     Ius harum lobortis ex, paulo iuvaret argumentum his ex. 
     Vel ne vocibus menandri constituto. 
     Populo salutatus patrioque est in. 
     Id laoreet propriae consulatu mel. 
     Assum prodesset at eos, ius at tota dolorum adversarium. 
     Ad inani impetus impedit duo, an quo tempor laoreet.</p>

     <p>Tantas similique eum id, idque veniam duo ei, ei commodo honestatis pri. 
     Ei sit ignota possit, ex vidisse iracundia his. 
     Eu propriae salutandi est. 
     Pro possim tibique at, at usu simul lobortis. 
     Latine incorrupte disputationi ad vel, integre detracto ei qui. 
     Sit ut illud scripta scribentur, has fastidii invenire voluptatibus in.</p>
    </content>
   </article>
   
   <article>
    <header class="article-header">
     <h1><a href="#">Second Article</a></h1>
    </header>
    
    <footer>
     <p class="post-info">by iRock</p>
    </footer>
    
    <content>
     <p>Lorem ipsum dolor sit amet, erant tempor fuisset ea nec. 
     Ius harum lobortis ex, paulo iuvaret argumentum his ex. 
     Vel ne vocibus menandri constituto. 
     Populo salutatus patrioque est in. 
     Id laoreet propriae consulatu mel. 
     Assum prodesset at eos, ius at tota dolorum adversarium. 
     Ad inani impetus impedit duo, an quo tempor laoreet.</p>

     <p>Tantas similique eum id, idque veniam duo ei, ei commodo honestatis pri. 
     Ei sit ignota possit, ex vidisse iracundia his. 
     Eu propriae salutandi est. 
     Pro possim tibique at, at usu simul lobortis. 
     Latine incorrupte disputationi ad vel, integre detracto ei qui. 
     Sit ut illud scripta scribentur, has fastidii invenire voluptatibus in.</p>
    </content>
   </article>
   
  </section>
  
  
  <!-- SIDEBAR -->
  <aside class="sidebar">
   <article>
    <h1><a href="#">Sidebar Article 1</a></h1>
    <p>Lorem ipsum dolor sit amet, erant tempor fuisset ea nec. 
     Ius harum lobortis ex, paulo iuvaret argumentum his ex.</p>
   </article>
   
   <article>
    <h1><a href="#">Sidebar Article 2</a></h1>
    <p>Lorem ipsum dolor sit amet, erant tempor fuisset ea nec. 
     Ius harum lobortis ex, paulo iuvaret argumentum his ex.</p>
   </article>
   
   <article>
    <h1><a href="#">Sidebar Article 3</a></h1>
    <p>Lorem ipsum dolor sit amet, erant tempor fuisset ea nec. 
     Ius harum lobortis ex, paulo iuvaret argumentum his ex.</p>
   </article>
  </aside>
  
  
  <!-- FOOTER -->
  <footer class="main-footer">
   <p>Copyright &copy; Øystein Jacobsen</p>
  </footer>
 </body>
</html>

但它不适用于 server

如有任何帮助，我们将不胜感激。

Answer 1

您需要运行在 $( document ).ready() 中编码，如下所示：

$( document ).ready(function() {
    $("#login").hover(function() {
      $("#login-form").slideToggle();
    });
});

这将确保您的代码仅在文档对象模型 (DOM) 准备就绪后执行。

并记得添加 jQuery 库：

<script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>

为什么 jquery 悬停在 jsfiddle 中有效，但在我的 html 布局中无效？

Why is jquery hover working in jsfiddle but not in my html layout?

javascript

html

css

jquery-hover