September 2022
Intermediate to advanced
585 pages
8h 17m
Chinese
Content preview from JavaScript 经典实例：第三版
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304
｜
第
12
章
demodiv
元素（节点）有五个子节点，而不是两个。
has child #text
has child P
has child #text
has child P
has child #text
如果想一窥
DOM
有多么错综复杂，可以打开
Firefox
或
Chrome
的开发者工具，然
后访问网页，使用开发者工具提供的检查工具。笔者在
Chrome
中打开一个简单的
页面，使用开发者工具显示元素树，结果如图
12-1
所示。
图
12
-
1
：使用 Chrome 的开发者工具检查一个网页的元素树
12.2
使用
forEach()
遍历
querySelectorAll()
获
取的结果
12.2.1
问题
你想遍历
querySelectorAll()
调用返回的
nodeList
。
12.2.2
方案
在现代浏览器中，你可以使用
forEach()
处理
NodeList
（
querySelectorAll()
返
回的集合）。
//
使用
querySelectorAll
查找页面中的所有列表项目
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.