html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>jquery</title>
<script type="text/javascript" src="js/jquery-3.0.0.min.js"></script>
//<script type="text/javascript" src="js/try.js" ></script>
<link rel="stylesheet" href="css/style.css" /> </head>
<body>
<div id="div1">div1
<div id="div2">div2
<p>
<a href="#">Hello</a>
</p>
</div>
</div>
</body>
</html>

  css

#div1 {
width:500px;
height:250px;
border:4px solid aquamarine; }
#div2 {
width:400px;
height:150px;
margin-left:10px ;
margin-top: 10px;
border:4px solid blue; }
p {
margin-left:10px ;
margin-top: 10px;
width:150px;
height:80px;
border:4px solid seagreen;
}

  效果:

jQuery遍历之向下遍历-LMLPHP

向下遍历后:

添加js

1.使用

children()方法
$(document).ready(function(){
$("#div1").children().css({border:"4px solid black"}) });

效果:

jQuery遍历之向下遍历-LMLPHP

2.使用find方法

js

$(document).ready(function(){
$("#div1").find("#div2").css({border:"4px solid black"}) });

  效果:

jQuery遍历之向下遍历-LMLPHP

children() 方法和find()方法的区别

1.

$(document).ready(function(){
$("#div1").find("p").css({border:"4px solid black"}) });

  

jQuery遍历之向下遍历-LMLPHP

2.

$(document).ready(function(){
$("#div1").children("p").css({border:"4px solid black"}) });

  效果:

jQuery遍历之向下遍历-LMLPHP

children方法获得的仅仅是元素一下级的子元素,即:immediate children。 
find方法获得所有下级元素,即:descendants of these elements in the DOM tree 
children方法的参数selector 是可选的(optionally),用来过滤子元素,但find方法的参数selector方法是必选的。 

2017-09-21                  20:37:02

05-28 02:06