Conversion of jquery objects and dom objects
##jquery The object is converted into a dom object: $()[subscript]
<!DOCTYPE html>
<html>
<head>
<title>php.cn</title>
<meta charset="utf-8" />
<script src="http://libs.baidu.com/jquery/1.10.2/jquery.min.js"></script>
<script>
function f1(){
//jquery对象 转化为 dom对象 进而调用dom的成员
$('#apple')[0].style.backgroundColor = "blue";
$('li')[1].style.backgroundColor = "brown";
}
</script>
<style type="text/css">
div {width:300px;height:200px; background-color:pink;}
</style>
</head>
<body>
<div id="apple"></div>
<ul>
<li>北京</li>
<li>上海</li>
<li>深圳</li>
</ul>
<input type="button" value="触发1" onclick="f1()" />
</body>
</html>Convert dom object to jquery object: $(dom object)
<!DOCTYPE html>
<html>
<head>
<title>php.cn</title>
<meta charset="utf-8" />
<script src="http://libs.baidu.com/jquery/1.10.2/jquery.min.js"></script>
<script>
function f1(){
//dom对象 变为 jquery对象: $(dom对象)
//注意：每次只能是"一个"dom对象变为jquery对象
var dv = document.getElementById('apple');
$(dv).css('background-color','green');
var lis = document.getElementsByTagName('li');
$(lis[2]).css('color','red');
}
</script>
<style type="text/css">
div {width:300px;height:200px; background-color:pink;}
</style>
</head>
<body>
<div id="apple"></div>
<ul>
<li>北京</li>
<li>上海</li>
<li>深圳</li>
</ul>
<input type="button" value="触发1" onclick="f1()" />
</body>
</html>