JQuery 后代元素与子元素的差别

后代元素即层级比当前元素低的所有元素，包括子元素

子元素即层级比当前元素低一级的直接元素

参见 http://blog.sina.com.cn/s/blog_775da6710100vzbr.html

<div>This is <strong>very</strong> important.</div>

<div>This is <em>really <strong>very</strong></em> important.</div>

 

以上是html。运行后在浏览器里是看到

 

This is very important.

This is really very important.

 

 

这样的样式，为了容易看到效果，我们不妨就尝试用添加css颜色来试一下

 

如果运行$("div strong").css("color","red");就是把div的后代元素strong变为红色。运行后是

 

This is very important.

This is really very important.

 

 如果运行$("div>strong").css("color","blue");就是把div的子元素strong变为蓝色。运行后是

 

This is very important.

This is really very important.