如何使手风琴与IE9兼容？

如何解决如何使手风琴与IE9兼容？

代码是从这里获取的：https://www.w3schools.com/howto/howto_js_accordion.asp

它可以在IE 11和IE 10中使用，但客户端希望它也可以在IE9中使用。

我知道...上帝帮助我！

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: '\002B';
  color: #777;
  font-weight: bold;
  float: right;
  margin-left: 5px;
}

.active:after {
  content: "\2212";
}

.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,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,quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

解决方法

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

您需要添加polyfill才能使其正常工作。

,

它在IE9中有效... 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: '\002B';
  color: #777;
  font-weight: bold;
  float: right;
  margin-left: 5px;
}

.active:after {
  content: "\2212";
}

.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,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,quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.</p>
</div>

,

我认为您是否可以使用Jquery和Juqery UI；您可以按照以下步骤进行操作，并且可以在IE9上运行。

$( 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>