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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>1.jQuyerr的工作原理</title>
<style type="text/css">
ul {
margin: 30px;
padding:10px;
overflow: hidden;
}
li {
list-style-type: none;
width: 40px;
height: 40px;
margin-left: 10px;
background-color: lightskyblue;
text-align: center;
line-height: 40px;
font-size: 1.2em;
font-weight: bolder;
float: left;
border-radius: 50px;
box-shadow: 2px 2px 2px #808080;
}
/*将对一个小球背景色换成绿色*/
/*li:first-child {
background-color: lightgreen;
}
li:nth-child(4) {
background-color: orangered;
color: white;
}*/
/*li:nth-child(4) ~ * {
background-color: lightgreen;
}*/
</style>
</head>
<body>
<ul>
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
<li>5</li>
<li>6</li>
<li>7</li>
<li>8</li>
<li>9</li>
<li>10</li>
</ul>
</body>
</html>
<script type="text/javascript">
// document.getElementsByTagName('li')[0]
// li.style.backgroundColor = 'lightgreen'
// querySelector()
// 只会返回满足条件的一个元素，但仅返回第一个
// var li = document.querySelector('li:first-child')
// li.style.backgroundColor = 'lightgreen'
// var li = document.querySelector('li:nth-child')
// li.style.backgroundColor = 'orangered'
// li.style.color = 'white'
// var li = document.querySelector('li:nth-child(4) ~ *')
// li.style.backgroundColor = 'lightgreen'
//querySelectorAll ()
// var li = document.querySelectorAll('li:nth-child(4) ~ *')
// alert(li.length)
// for (var i=0;i<li.length;i++){
// li[i].style.backgroundColor = 'lightgreen'
// }
</script>
<script type="text/javascript" src="http://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"></script>
<script type="text/javascript">
$('li:nth-child(4)~*').css('background-color','lightgreen')
</script>点击 "运行实例" 按钮查看在线实例
