打开第一支JavaScript手风琴

时间:2017-10-13 19:01:26

标签: javascript accordion

如何在JavaScript手风琴中打开第一个?它是一个基本的手风琴,+用于打开,-用于关闭。我是新手,我只是在寻找jQuery手风琴的解决方案。还想知道jQuery是否是手风琴的最佳选择?

这里是jsFiddle:https://jsfiddle.net/dmkx8hg0/

以下是代码:

<head>
<style>
button.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;
}

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

button.accordion:after {
    content: '\002B';
    color: #777;
    font-weight: bold;
    float: right;
    margin-left: 5px;
}

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

div.panel {
    padding: 0 18px;
    background-color: white;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.2s ease-out;
}
</style>
</head>
<body>
<button class="accordion">Section 1</button>
<div class="panel">
    <p>content</p>
</div>

<button class="accordion">Section 2</button>
<div class="panel">
    <p>content</p>
</div>

<button class="accordion">Section 3</button>
<div class="panel">
    <p>content</p>
</div>

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

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

2 个答案:

答案 0 :(得分:0)

您只需触发javascript中第一个元素的click事件即可。 Here's an updated fiddle

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

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

答案 1 :(得分:0)

为什么不直接向面板添加活动的类名和样式,如果您想要打开第一个面板,它应该可以解决问题。 <button class="accordion active">Section 1</button> <div class="panel" style="max-height: 89px;"> <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.</p> </div>