HTML5 Image upload preprocessing, a plug-in that only has HTML5 front-end upload page without background processing, you can use it directly ~ yes for HTML5 Interested friends can research it.
The style is a bit ugly, but it’s still okay
Code:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>PHP中文网</title>
</head>
<body>
<script>
window.onload = function () {
var input = document.createElement('input');
input.type = 'file';
input.addEventListener('change', function () {
var file = this.files[0];
var img = document.createElement('img');
img.src = window.URL.createObjectURL(file);
img.onload = function () {
var canvas = document.createElement('canvas');
var ctx = canvas.getContext('2d');
var MAX_WIDTH = 150;
var MAX_HEIGHT = 200;
var width = img.width;
var height = img.height;
if (width > height) {
if (width > MAX_WIDTH) {
height *= MAX_WIDTH / width;
width = MAX_WIDTH;
}
} else {
if (height > MAX_HEIGHT) {
width *= MAX_HEIGHT / height;
height = MAX_HEIGHT;
}
}
canvas.width = width;
canvas.height = height;
ctx.drawImage(img, 0, 0, width, height);
document.body.appendChild(canvas);
var btn = document.createElement('button');
btn.innerHTML = '上传';
document.body.appendChild(btn);
btn.addEventListener('click', function() {
/*
toBlob的兼容性问题使用
https://github.com/blueimp/JavaScript-Canvas-to-Blob 这个库，就可以解决
*/
canvas.toBlob(function(blob) {
var form = new FormData();
form.append('file', blob);
fetch('/api/upload', {method: 'POST', body: form});
});
}, false);
};
// document.body.appendChild(img); 原始图片是不用展示出来的
}, false);
document.body.appendChild(input);
};
</script>
</body>
</html>The above is the HTML5 image upload preset Processing, you can modify it and use it directly, or you can study it. For more articles and source codes, please go to PHP Chinese website to search
Related recommendations:
Use HTML5 to create screen gesture unlock function
A brief discussion on the future development of HTML5
The above is the detailed content of HTML5 image upload preprocessing. For more information, please follow other related articles on the PHP Chinese website!
The Origins of JavaScript: Exploring Its Implementation LanguageApr 29, 2025 am 12:51 AMJavaScript originated in 1995 and was created by Brandon Ike, and realized the language into C. 1.C language provides high performance and system-level programming capabilities for JavaScript. 2. JavaScript's memory management and performance optimization rely on C language. 3. The cross-platform feature of C language helps JavaScript run efficiently on different operating systems.
Behind the Scenes: What Language Powers JavaScript?Apr 28, 2025 am 12:01 AMJavaScript 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 of Python and JavaScript: Trends and PredictionsApr 27, 2025 am 12:21 AMThe 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.
Python vs. JavaScript: Development Environments and ToolsApr 26, 2025 am 12:09 AMBoth 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.
Is JavaScript Written in C? Examining the EvidenceApr 25, 2025 am 12:15 AMYes, 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's Role: Making the Web Interactive and DynamicApr 24, 2025 am 12:12 AMJavaScript 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: The Connection ExplainedApr 23, 2025 am 12:07 AMC 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.
From Websites to Apps: The Diverse Applications of JavaScriptApr 22, 2025 am 12:02 AMJavaScript 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.
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
MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function
SublimeText3 Chinese version
Chinese version, very easy to use
ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment
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.
