Home Web Front-end HTML Tutorial 根据屏幕大小,加载不同大小的图片_html/css_WEB-ITnose

根据屏幕大小,加载不同大小的图片_html/css_WEB-ITnose

May 14, 2018 pm 03:34 PM

引言今天要介绍的东西,很简单,但是对于前端响应式的时候是个很重要的知识;我们在用bootstrap这类前端框架时,虽然页面局部通过media query实现了,页面始终无滚动条,响应式页面。但是,bootstrap里面的img-responsive类只是通过设置图片100%,并没有真正的实现在手机上和电脑端加载不同大小的图片。
代码其实很简单

<!DOCTYPE html><html><head>    
<meta charset="UTF-8">    
<meta name="viewport" content="width=device-width,initial-scale=1">    
<title>Document</title>    
<script>        
document.createElement( "picture" );       
</script></head><body>    
<picture>            
<source srcset="pic1.png" media="(max-width: 600px)">            
<source srcset="pic2.png" media="(max-width: 800px)">            
<img srcset="pic3.png" alt="pic">        
</picture></body></html>
Copy after login

下面是在浏览器中的结果,我们打开Chrome浏览器,按f12后查看网络请求。

首先是三张图片

pic1.png

默认情况下,屏幕全屏,宽度大于800

pic2.png

当页面宽度在600px-800px((600,800])之间时

pic3.png

最后是页面小于等于600px

pic4.png

针对上面的代码,我们解释一下:其中的img元素是默认情况下显示的图片源,在其上面的两个source元素则是在特定媒体查询(media queries)条件下显示的图片。

这样我们只需要通过像写熟悉的css的媒体查询一样写代码,就能实现根据浏览器窗口大小,动态加载图片。在手机上,就不用加载一个电脑端才显示的大图。

GitHub上有位大神,基于以上的原则,编写了一个picfill的项目,大家有兴趣的可以去git上查看。


Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

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

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1653
14
PHP Tutorial
1251
29
C# Tutorial
1224
24
Is HTML easy to learn for beginners? Is HTML easy to learn for beginners? Apr 07, 2025 am 12:11 AM

HTML is suitable for beginners because it is simple and easy to learn and can quickly see results. 1) The learning curve of HTML is smooth and easy to get started. 2) Just master the basic tags to start creating web pages. 3) High flexibility and can be used in combination with CSS and JavaScript. 4) Rich learning resources and modern tools support the learning process.

The Roles of HTML, CSS, and JavaScript: Core Responsibilities The Roles of HTML, CSS, and JavaScript: Core Responsibilities Apr 08, 2025 pm 07:05 PM

HTML defines the web structure, CSS is responsible for style and layout, and JavaScript gives dynamic interaction. The three perform their duties in web development and jointly build a colorful website.

Understanding HTML, CSS, and JavaScript: A Beginner's Guide Understanding HTML, CSS, and JavaScript: A Beginner's Guide Apr 12, 2025 am 12:02 AM

WebdevelopmentreliesonHTML,CSS,andJavaScript:1)HTMLstructurescontent,2)CSSstylesit,and3)JavaScriptaddsinteractivity,formingthebasisofmodernwebexperiences.

Gitee Pages static website deployment failed: How to troubleshoot and resolve single file 404 errors? Gitee Pages static website deployment failed: How to troubleshoot and resolve single file 404 errors? Apr 04, 2025 pm 11:54 PM

GiteePages static website deployment failed: 404 error troubleshooting and resolution when using Gitee...

What is an example of a starting tag in HTML? What is an example of a starting tag in HTML? Apr 06, 2025 am 12:04 AM

AnexampleofastartingtaginHTMLis,whichbeginsaparagraph.StartingtagsareessentialinHTMLastheyinitiateelements,definetheirtypes,andarecrucialforstructuringwebpagesandconstructingtheDOM.

How to use CSS3 and JavaScript to achieve the effect of scattering and enlarging the surrounding pictures after clicking? How to use CSS3 and JavaScript to achieve the effect of scattering and enlarging the surrounding pictures after clicking? Apr 05, 2025 am 06:15 AM

To achieve the effect of scattering and enlarging the surrounding images after clicking on the image, many web designs need to achieve an interactive effect: click on a certain image to make the surrounding...

HTML, CSS, and JavaScript: Essential Tools for Web Developers HTML, CSS, and JavaScript: Essential Tools for Web Developers Apr 09, 2025 am 12:12 AM

HTML, CSS and JavaScript are the three pillars of web development. 1. HTML defines the web page structure and uses tags such as, etc. 2. CSS controls the web page style, using selectors and attributes such as color, font-size, etc. 3. JavaScript realizes dynamic effects and interaction, through event monitoring and DOM operations.

How to implement adaptive layout of Y-axis position in web annotation? How to implement adaptive layout of Y-axis position in web annotation? Apr 04, 2025 pm 11:30 PM

The Y-axis position adaptive algorithm for web annotation function This article will explore how to implement annotation functions similar to Word documents, especially how to deal with the interval between annotations...

See all articles