单一按钮显示/隐藏

以上是运行的效果,可以实现列表的收放。

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>单一按钮显示/隐藏</title>
<link href="../CSS/miaov_style.css" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="../JS/miaov.js">
</script>
</head>

<body>

<div id="drop" class="down_list">
    <h2 class="up">播放列表</h2>
    <ul>
        <li><a href="#">玩爱之徒 - 蔡依林</a></li>
        <li><a href="#">原谅我就是这样的女生 - 戴佩妮</a></li>
        <li><a href="#">猜不透 - 丁当</a></li>
        <li><a href="#">自导自演 - 周杰伦</a></li>
        <li><a href="#">浪漫窝 - 弦子</a></li>
        <li><a href="#">流年 - 王非</a></li>
    </ul>
</div>

</body>
</html>
@charset "utf-8";
/* CSS Document */

* { padding: 0; margin: 0; }
li { list-style: none; }
body { background: #f6f9fc; }

.down_list { width: 200px;
    overflow: hidden;
    border: 1px solid #aab4bc;
    background: url(../IMG/down_list_h2_bg.gif) repeat-x;
    margin: 50px auto 0; }
.down_list h2 { height: 25px;
    line-height: 25px;
    border: 1px solid #dee3e6;
    border-top: 1px solid #f3f5f7;
    padding-left: 10px;
    font-size: 14px;
    font-weight: normal;
    color: #57646e;
    cursor: pointer;
}
.down { background: url(../IMG/down.gif) no-repeat 180px center; }
.up { background: url(../IMG/up.gif) no-repeat 180px center; }
.down_list ul {
    width: 200px;
    overflow: hidden;
    background: #e9edf2;
    font-size: 12px;
}
.down_list li { width: 200px; float: left; }
.down_list a { display: block; line-height: 25px; padding-left: 10px; color: #6b7980; text-decoration: none; }
.down_list a:hover { background: #fff; text-decoration: underline; }
window.onload=function ()
{
    var oDiv=document.getElementById('drop');
    var oH2=oDiv.getElementsByTagName('h2')[0];
    var oUl=oDiv.getElementsByTagName('ul')[0];
    
    oH2.onclick=showHideUl;
}

function showHideUl()
{
    var oDiv=document.getElementById('drop');
    var oUl=oDiv.getElementsByTagName('ul')[0];
    var oH2=oDiv.getElementsByTagName('h2')[0];
    
    if(oUl.style.display === 'none')
    {
        oUl.style.display='block';
        oH2.className='up';
    }
    else
    {
        oUl.style.display='none';
        oH2.className='down';
    }

}
原文地址:https://www.cnblogs.com/1322957664qqcom/p/11268606.html