Will HTML files be cached?
Feb 19, 2024 pm 01:51 PMTitle: HTML file caching mechanism and code examples
Introduction: When writing web pages, we often encounter browser cache problems. This article will introduce the caching mechanism of HTML files in detail and provide some specific code examples to help readers better understand and apply this mechanism.
1. Browser caching principle
In the browser, whenever a web page is accessed, the browser will first check whether there is a copy of the web page in the cache. If there is, the web page content is obtained directly from the cache. This is the basic principle of browser caching. The advantage of the browser caching mechanism is that it can improve web page loading speed, reduce network requests, and save bandwidth.
2. HTML caching methods
The caching of HTML files can be controlled in the following two ways:
-
Expires and Cache-Control
Through Adding the Expires and Cache-Control fields to the HTTP response header can control the time the browser caches files. The specific sample code is as follows:HTTP/1.1 200 OK Content-Type: text/html Cache-Control: max-age=3600 Expires: Wed, 04 Aug 2022 08:00:00 GMT <!DOCTYPE html> <html> <!-- HTML頁面內(nèi)容 --> </html>
In the above sample code, the Cache-Control field specifies the maximum cache time of 3600 seconds, which is one hour, and the Expires field specifies the cache expiration time as August 4, 2022. 8 o'clock.
Last-Modified and If-Modified-Since
Indicate the last modification time of the file by adding the Last-Modified field in the HTTP response header. After the browser caches the file, it will add the If-Modified-Since field the next time it requests the file and send the last modification time of the last cached file to the server. The server will determine whether the file has been updated based on this time. If the file is not updated, a 304 Not Modified response is returned and the browser continues to use the cached file. The specific sample code is as follows:HTTP/1.1 200 OK Content-Type: text/html Last-Modified: Mon, 01 Aug 2022 12:00:00 GMT <!DOCTYPE html> <html> <!-- HTML頁面內(nèi)容 --> </html>
In the above sample code, the Last-Modified field specifies the last modification time of the file as 12:00 on August 1, 2022.
3. Cache control strategy
According to actual needs, we can formulate different caching strategies based on the content of the file or other conditions to better control the browser cache.
Static file caching
For static files that do not change frequently, you can set a longer cache time so that the browser can cache the file persistently and reduce requests to the server. For example, for static files such as CSS, JavaScript, and images, you can set the cache time to one year. The sample code is as follows:HTTP/1.1 200 OK Content-Type: text/css Cache-Control: max-age=31536000 /* CSS文件內(nèi)容 */
Dynamic file caching
For dynamic files that change frequently, you can control the cache time to be shorter to ensure that the browser can obtain the latest files in a timely manner. content. For example, dynamically generated HTML files can not set any cache fields, allowing the browser to request the latest version every time. The sample code is as follows:HTTP/1.1 200 OK Content-Type: text/html Cache-Control: no-cache, no-store, must-revalidate Pragma: no-cache Expires: 0 <!DOCTYPE html> <html> <!-- HTML頁面內(nèi)容 --> </html>
Version control cache
Keep the file name unchanged when the file is updated, by adding a version number or timestamp to the file name or URL. Make the browser think it is a new file and reload the file. The sample code is as follows:<link rel="stylesheet" href="/static/style.css?v=1.0"> <script src="/static/script.js?t=1627836018"></script>
4. Summary
The caching of HTML files is achieved by setting the corresponding fields in the HTTP response header. By properly controlling cache time and policies, web page loading speed and user experience can be improved. In actual development, appropriate caching methods and strategies are selected based on the content and characteristics of the file. We hope that the code examples provided in this article can help readers better understand and use the HTML caching mechanism.
The above is the detailed content of Will HTML files be cached?. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

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

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

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

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

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

Hot Topics

?In today's increasingly popular digital asset trading, it is particularly important to understand how to safely and effectively withdraw your digital assets. As a world-renowned digital asset trading platform, ok exchange provides convenient currency withdrawal services. This tutorial will analyze in detail the steps of withdrawing coins on the ok exchange, things to note, and some common questions and answers to help users complete asset transfer smoothly and ensure asset security. Whether you are using ok exchange for withdrawals for the first time or want to further understand the withdrawal process, this article will provide you with clear and practical guidance.

Binance is one of the world's well-known digital asset trading platforms, providing users with a wide range of digital currency trading services, including mainstream assets such as Bitcoin and Ethereum. The platform is trusted by users around the world for its rich trading pairs, strong technical support and strict security measures. This article will provide you with the download and installation guidance of Binance's official app, and provide an official download link. Click the download link provided by this article to directly download the latest version of the official application, ensuring that your trading journey is safe and convenient.

The latest version of Digital Currency Exchange 2025 is a world-leading digital asset trading application, committed to providing users with secure, stable and convenient trading services for mainstream digital currencies such as Bitcoin and Ethereum. Its simple and intuitive operation interface and powerful functional modules make it easy for both novices and senior traders to get started.

Ouyi APP is a platform that provides cryptocurrency trading and financial services. It supports various trading functions such as spot, contracts, options, and has leverage, lending, and financial management. Its interface is simple and intuitive, suitable for all kinds of users, and pays attention to technical security. To ensure safety, it is recommended to download the application through the official website. The steps for downloading and installation are as follows: 1. Visit Ouyi official website and find the "APP Download" entrance; 2. Select the corresponding download method according to the device or scan the QR code; 3. Ensure that the file source is reliable and avoid unknown sources of third parties; 4. Download from the app store and click on the installation directly to keep the network stable; 5. If the installation file needs to be manually run and authorized for installation permissions; 6. Click the icon to start the application after the installation is completed; 7. Register or log in to the account and set a strong

Decentralized exchanges (DEXs) have attracted attention in the cryptocurrency field in recent years. Unlike traditional centralized exchanges (CEX), DEX operates on blockchain and aims to provide a way to trade without trusting intermediaries. When a user trades on a DEX, the assets are usually kept in their wallet rather than stored in an escrow account on the exchange. This model brings unique security advantages, but it also comes with new challenges.

The latest version of Binance is v2.102.5, and the update tutorial is: 1. Click the download link in the web page; 2. Authorize the installation permission of "Allow installation from unknown sources"; 3. Find the downloaded APk and click to install; 4. Click the installed application to open it.

As a well-known digital asset trading platform, Ouyi OKX provides users with convenient trading services and a variety of digital currency choices. In order to facilitate users to trade and manage assets anytime, anywhere, Ouyi OKX has launched an official mobile application. This article will provide you with the official download link of the application to help you get and install it smoothly. Click the download link provided in this article to start the download process.

The latest version of Binance is v2.102.5, and the update tutorial is: 1. Click the download link in the web page; 2. Authorize the installation permission of "Allow installation from unknown sources"; 3. Find the downloaded APk and click to install; 4. Click the installed application to open it.
