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问如何使下拉菜单向右展开而不是向下展开？
EN

Stack Overflow用户

提问于 2020-05-13 13:56:08

回答 2查看 841关注 0票数 0

对于这个带有下拉列表的侧栏示例：

https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_sidenav_dropdown

在我的例子中，dropdown将不会是用户友好的，因为有很多项，所以我不认为向下扩展dropdown是一个好主意。我想展开并指向右侧，如下所示：

我该怎么做呢？提前感谢！

javascript

html

css

回答 2

Stack Overflow用户

回答已采纳

发布于 2020-05-13 14:14:56

我在一个容器中添加了位置相对的按钮和下拉列表，并添加了这个css：

.dropdown-container {
   position: absolute;
   width: 100%;
   left: 100%;
   z-index: 1;
   top: 0px;
}

请参阅this working fiddle

票数 1

Stack Overflow用户

发布于 2020-05-13 18:00:45

没什么，只需添加一个列表并将其设置为固定，然后调整页边距

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
<style>
body {
  font-family: "Lato", sans-serif;
}

/* Fixed sidenav, full height */
.sidenav {
  height: 100%;
  width: 200px;
  position: fixed;
  z-index: 2221;
  top: 0;
  left: 0;
  background-color: #111;
 
  padding-top: 20px;
}

/* Style the sidenav links and the dropdown button */
.sidenav a, .dropdown-btn {
  padding: 6px 8px 6px 16px;
  text-decoration: none;
  font-size: 20px;
  color: #818181;
  display: block;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  cursor: pointer;
  outline: none;
}

/* On mouse-over */
.sidenav a:hover, .dropdown-btn:hover {
  color: #f1f1f1;
}

/* Main content */
.main {
  margin-left: 200px; /* Same as the width of the sidenav */
  font-size: 20px; /* Increased text to enable scrolling */
  padding: 0px 10px;
}

/* Add an active class to the active dropdown button */
.active {
  background-color: green;
  color: white;
}

/* Dropdown container (hidden by default). Optional: add a lighter background color and some left padding to change the design of the dropdown content */
.dropdown-container {
  display: none;
  background-color: #262626;
  padding-left: 8px;
}

/* Optional: Style the caret down icon */
.fa-caret-down {
  float: right;
  padding-right: 8px;
}

/* Some media queries for responsiveness */
@media screen and (max-height: 450px) {
  .sidenav {padding-top: 15px;}
  .sidenav a {font-size: 18px;}
}

.dropdown-container ul { 
  position: fixed; 
  margin-left:192px;     
  background-color: #111; 
  list-style: none; 
  margin-top: -36px;
  padding: 0;
}

.dropdown-container ul {
  width: 150px;
}
</style>
</head>
<body>

<div class="sidenav">
  <a href="#about">About</a>
  <a href="#services">Services</a>
  <a href="#clients">Clients</a>
  <a href="#contact">Contact</a>
  <button class="dropdown-btn">Dropdown 
    <i class="fa fa-caret-down"></i>
  </button>
  <div class="dropdown-container">
	<ul>
     <li><a href="#">Link 1</a></li>
     <li><a href="#">Link 2</a></li>
     <li><a href="#">Link 3</a></li>
    
    </ul>

  </div>
  <a href="#contact">Search</a>
</div>

<div class="main">
  <h2>Sidebar Dropdown</h2>
  <p>Click on the dropdown button to open the dropdown menu inside the side navigation.</p>
  <p>This sidebar is of full height (100%) and always shown.</p>
  <p>Some random text..</p>
</div>

<script>
/* Loop through all dropdown buttons to toggle between hiding and showing its dropdown content - This allows the user to have multiple dropdowns without any conflict */
var dropdown = document.getElementsByClassName("dropdown-btn");
var i;

for (i = 0; i < dropdown.length; i++) {
  dropdown[i].addEventListener("click", function() {
  this.classList.toggle("active");
  var dropdownContent = this.nextElementSibling;
  if (dropdownContent.style.display === "block") {
  dropdownContent.style.display = "none";
  } else {
  dropdownContent.style.display = "block";
  }
  });
}
</script>

</body>
</html>