This time I will bring you the use of H5 cache Manifest. What are the precautions for using H5 cache Manifest? The following is a practical case, let's take a look. In the app
Updateh5 page has always had a cache problem. By default, by doing nothing, the app has a certain amount of space to cache pages. The update will be loaded immediately after it is started. When the app cache space is available, the update will not be downloaded. Android can clear cache space, but iOS can only uninstall and reinstall (are u kidding me?). This is the worst case scenario, you can change the address. no-cache
After noticing this, add no-cache.
<meta>
to tell the browser not to cache the page. In fact, when the page has not changed, the request is 304, and if the page has changed, it is 200. So adding no-cache does not mean that it will be downloaded completely every time, but that it will be downloaded again when it is updated. But at this time, different mobile phones still perform differently. 4s and 6sp are different. Visit the same page and modify the js. The 4s has been updated, but the 6sp is still the same. How to fix it, because there is still cache on the server side. First set the nginx cache:
location / { root html; expires -1; index index.html index.htm; }
and need to restart nginx:
nginx -s reload
At this time, 6sp has also been updated.
But always restarting nginx is not a solution, it may cause some requests to be lost. And in this case, it is completely unusable offline. For example, when the Internet is disconnected and I try to send a message, the originally set picture with a red exclamation mark and the character's avatar cannot be displayed. Of course, you can convert it into a base64
stringto solve this problem. Base64 is very long and takes up space wherever it is placed. How to solve it, manifest
no-cache+update file name+update address to be testedmanifest
For introduction, you can read w3shool first: http:/ /www.w3school.com.cn/html5/html_5_app_cache.asp , here is the usage.
1.Set html
2.Set cache directory
CACHE MANIFEST #v1.0.0.0#需要缓存的文件js/zepto.js#不需要缓存的页面 NETWORK:*#无法访问页面 FALLBACK404.html
3.Set nginx mime
text/cache-manifest appcache;
mime types files are all in the conf directory. After starting nginx. At this time, the page will load:
This picture illustrates two things. One is that the process will first download index.appcache, and then the checking event and download event will be triggered one after another. , progress event and updateReady event. Two of them cache the current page by default. And it actually takes a parameter and caches it. It seems that as long as the current pages with different addresses are cached (I only wrote one zepto in the cache directory above). Refresh the page again:
If index.appcache is not updated, the check will not be triggered.
Loading cached files
is 200, and the size column is from cache. The one loaded from the browser is 304, one is a few milliseconds, and the other is more than ten milliseconds. F12 enters developer mode, and you can see the cached files in the Application cache column.
#But it cannot be cleaned in this place. It needs to be cleaned by clear storage in Application.
Update cached files
The most obvious one is the homepage, which is cached by default. At this time, it will have no effect if you change the content of the homepage without modifying index.appache. For example, if you delete the
reference of a js, the client still downloads the js. At this time, you need to modify this cache file: #不需要缓存的页面
NETWORK:
mobile/index.html
*
Notice that although index.appache and index are at the same level, index.html cannot be written, and the path equivalent to the website must be written. The same is true for other resources. At this time, the update is triggered, but the page is still loaded with cached resources, so another process needs to be done:
window.applicationCache.addEventListener("updateready", function(){ location.reload() });
这样才会加载最新的页面。如果首页再发生修改,可以随意(加个空格,加空行)修改缓存文件,就能触发更新。所以剩下的问题就是记得在更新资源之后记得更新缓存文件。建议就是不变的资源(框架样式,框架js,图片)缓存下来,经常要修改的js就让浏览器缓存吧。现在这样就避免了reload nginx。这个效果要比加no-cache的方法好。当然,如果无所谓消息或者reload的影响。no-cache还是很方便,毕竟这个index.appache一旦加上,难以去掉,除非清理缓存。
相信看了本文案例你已经掌握了方法,更多精彩请关注php中文网其它相关文章!
推荐阅读:
The above is the detailed content of Use of H5 cache Manifest. For more information, please follow other related articles on the PHP Chinese website!

JavaScript runs in browsers and Node.js environments and relies on the JavaScript engine to parse and execute code. 1) Generate abstract syntax tree (AST) in the parsing stage; 2) convert AST into bytecode or machine code in the compilation stage; 3) execute the compiled code in the execution stage.

The future trends of Python and JavaScript include: 1. Python will consolidate its position in the fields of scientific computing and AI, 2. JavaScript will promote the development of web technology, 3. Cross-platform development will become a hot topic, and 4. Performance optimization will be the focus. Both will continue to expand application scenarios in their respective fields and make more breakthroughs in performance.

Both Python and JavaScript's choices in development environments are important. 1) Python's development environment includes PyCharm, JupyterNotebook and Anaconda, which are suitable for data science and rapid prototyping. 2) The development environment of JavaScript includes Node.js, VSCode and Webpack, which are suitable for front-end and back-end development. Choosing the right tools according to project needs can improve development efficiency and project success rate.

Yes, the engine core of JavaScript is written in C. 1) The C language provides efficient performance and underlying control, which is suitable for the development of JavaScript engine. 2) Taking the V8 engine as an example, its core is written in C, combining the efficiency and object-oriented characteristics of C. 3) The working principle of the JavaScript engine includes parsing, compiling and execution, and the C language plays a key role in these processes.

JavaScript is at the heart of modern websites because it enhances the interactivity and dynamicity of web pages. 1) It allows to change content without refreshing the page, 2) manipulate web pages through DOMAPI, 3) support complex interactive effects such as animation and drag-and-drop, 4) optimize performance and best practices to improve user experience.

C and JavaScript achieve interoperability through WebAssembly. 1) C code is compiled into WebAssembly module and introduced into JavaScript environment to enhance computing power. 2) In game development, C handles physics engines and graphics rendering, and JavaScript is responsible for game logic and user interface.

JavaScript is widely used in websites, mobile applications, desktop applications and server-side programming. 1) In website development, JavaScript operates DOM together with HTML and CSS to achieve dynamic effects and supports frameworks such as jQuery and React. 2) Through ReactNative and Ionic, JavaScript is used to develop cross-platform mobile applications. 3) The Electron framework enables JavaScript to build desktop applications. 4) Node.js allows JavaScript to run on the server side and supports high concurrent requests.

Python is more suitable for data science and automation, while JavaScript is more suitable for front-end and full-stack development. 1. Python performs well in data science and machine learning, using libraries such as NumPy and Pandas for data processing and modeling. 2. Python is concise and efficient in automation and scripting. 3. JavaScript is indispensable in front-end development and is used to build dynamic web pages and single-page applications. 4. JavaScript plays a role in back-end development through Node.js and supports full-stack development.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Zend Studio 13.0.1
Powerful PHP integrated development environment

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

SublimeText3 English version
Recommended: Win version, supports code prompts!
