如何让手风琴兼容IE9？

Question

代码取自这里：https://www.w3schools.com/howto/howto_js_accordion.asp

它适用于 IE 11 和 IE 10，但客户希望它也适用于 IE9。

我知道...大神帮帮我！

var acc = document.getElementsByClassName("accordion");
var i;

for (i = 0; i < acc.length; i++) {
  acc[i].addEventListener("click", function() {
    this.classList.toggle("active");
    var panel = this.nextElementSibling;
    if (panel.style.maxHeight) {
      panel.style.maxHeight = null;
    } else {
      panel.style.maxHeight = panel.scrollHeight + "px";
    } 
  });
}

.accordion {
  background-color: #eee;
  color: #444;
  cursor: pointer;
  padding: 18px;
  width: 100%;
  border: none;
  text-align: left;
  outline: none;
  font-size: 15px;
  transition: 0.4s;
}

.active, .accordion:hover {
  background-color: #ccc;
}

.accordion:after {
  content: '[=11=]2B';
  color: #777;
  font-weight: bold;
  float: right;
  margin-left: 5px;
}

.active:after {
  content: "12";
}

.panel {
  padding: 0 18px;
  background-color: white;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.2s ease-out;
}

<button class="accordion">Section 1</button>
<div class="panel">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

<button class="accordion">Section 2</button>
<div class="panel">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

<button class="accordion">Section 3</button>
<div class="panel">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

Answer 1

这里的问题是 classList 属性 is not supported in IE9.

您需要添加一个 polyfill 才能正常工作。

Answer 2

我想如果你可以使用 Jquery 和 Jquery UI；你猫按照下面的方法做，它在 IE 9 上工作。

$( function() {
    $( "#accordion" ).accordion();
  } );

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css">
  <link rel="stylesheet" href="/resources/demos/style.css">
  <script src="https://code.jquery.com/jquery-1.12.4.js"></script>
  <script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
<div id="accordion">
  <h3>Section 1</h3>
  <div>
    <p>
    Mauris mauris ante, blandit et, ultrices a, suscipit eget, quam. Integer
    ut neque. Vivamus nisi metus, molestie vel, gravida in, condimentum sit
    amet, nunc. Nam a nibh. Donec suscipit eros. Nam mi. Proin viverra leo ut
    odio. Curabitur malesuada. Vestibulum a velit eu ante scelerisque vulputate.
    </p>
  </div>
  <h3>Section 2</h3>
  <div>
    <p>
    Sed non urna. Donec et ante. Phasellus eu ligula. Vestibulum sit amet
    purus. Vivamus hendrerit, dolor at aliquet laoreet, mauris turpis porttitor
    velit, faucibus interdum tellus libero ac justo. Vivamus non quam. In
    suscipit faucibus urna.
    </p>
  </div>
  <h3>Section 3</h3>
  <div>
    <p>
    Nam enim risus, molestie et, porta ac, aliquam ac, risus. Quisque lobortis.
    Phasellus pellentesque purus in massa. Aenean in pede. Phasellus ac libero
    ac tellus pellentesque semper. Sed ac felis. Sed commodo, magna quis
    lacinia ornare, quam ante aliquam nisi, eu iaculis leo purus venenatis dui.
    </p>
    <ul>
      <li>List item one</li>
      <li>List item two</li>
      <li>List item three</li>
    </ul>
  </div>
  <h3>Section 4</h3>
  <div>
    <p>
    Cras dictum. Pellentesque habitant morbi tristique senectus et netus
    et malesuada fames ac turpis egestas. Vestibulum ante ipsum primis in
    faucibus orci luctus et ultrices posuere cubilia Curae; Aenean lacinia
    mauris vel est.
    </p>
    <p>
    Suspendisse eu nisl. Nullam ut libero. Integer dignissim consequat lectus.
    Class aptent taciti sociosqu ad litora torquent per conubia nostra, per
    inceptos himenaeos.
    </p>
  </div>
</div>

Answer 3

它适用于 IE9 ... classList 在 IE 9 中不支持

var acc = document.getElementsByClassName("accordion");
var i;

for (i = 0; i < acc.length; i++) {
  acc[i].addEventListener("click", function() {
  
  
  if (this.classList) {
  this.classList.toggle("active");
} else {
  // For IE9
  var classes = this.className.split(" ");
  var i = classes.indexOf("active");

  if (i >= 0)
    classes.splice(i, 1);
  else
    classes.push("active");
    this.className = classes.join(" ");
}
  
  
    //this.classList.toggle("active");
    var panel = this.nextElementSibling;
    if (panel.style.maxHeight) {
      panel.style.maxHeight = null;
    } else {
      panel.style.maxHeight = panel.scrollHeight + "px";
    } 
  });
}

.accordion {
  background-color: #eee;
  color: #444;
  cursor: pointer;
  padding: 18px;
  width: 100%;
  border: none;
  text-align: left;
  outline: none;
  font-size: 15px;
  transition: 0.4s;
}

.active, .accordion:hover {
  background-color: #ccc;
}

.accordion:after {
  content: '[=11=]2B';
  color: #777;
  font-weight: bold;
  float: right;
  margin-left: 5px;
}

.active:after {
  content: "12";
}

.panel {
  padding: 0 18px;
  background-color: white;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.2s ease-out;
}

<button class="accordion">Section 1</button>
<div class="panel">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

<button class="accordion">Section 2</button>
<div class="panel">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

<button class="accordion">Section 3</button>
<div class="panel">
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

如何让手风琴兼容IE9？

How to make accordion compatible with IE9?

html

javascript

accordion

internet-explorer-9