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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422
｜
第
16
章
caches.keys().then(keyList => {
return
Promise.all(
keyList.map(key => {
if
(key !== cacheVersion) {
return
caches.
delete
(key);
}
})
);
})
);
});
图
16
-
3
：安装服务职程后，应用离线也能加载文件
16.3.3
讨论
渐进式
Web
应用是可由用户安装的
Web
应用，具有一定的离线功能。这些功能可
以让
Web
应用模拟原生应用的某些优秀功能，同时提供
Web
的开放性。
Web
应用的清单是一个
JSON
文件，提供有关应用的信息。这个文件中可以包含的
键值列表如下所示。
编写
Web
应用
｜
423
background_color
启动界面背景颜色代码。
categories
一个字符串数组，指定应用所属分类。
description
一个字符串，描述应用。
dir
显示字符的方向。可以是
auto
、
ltr
（从左到右）或
rtl
（从右到左）。
display
首选的显示模式。可以是
browser
，即默认的浏览器行为，也可以是
fullscreen
，在某些设备中去除浏览器窗格。
iarc_rating_id
国际年龄评级（
International ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
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.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
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.