search
HomeWeb Front-endJS TutorialImplementing file upload function based on nodejs express(4.x)_node.js

Nodejs is a young programming framework, full of vitality and unlimited passion, and has always been updated rapidly. Express, the official web development library based on Nodejs, is also developing simultaneously, with a major version upgrade every year and even major surgery on the bottom layer of the framework. In Express4, the middleware library connect was replaced by multiple more fine-grained libraries. The obvious benefit is that these middleware can be updated and released more freely and will not be affected by the Express release cycle; but the problem is also very difficult. It is not compatible with previous versions, and upgrading means modifying the code.

After a period of research and exploration, I found that the ways to achieve uploading are: 1. express middleware multer module (this is the most efficient, natively supported in express3.x, and became an independent module in express4.x), 2. connect-multiparty module (but it is not officially recommended now), 3. Use the multiparty module to implement (this method is more common), 4. Use the formidable plug-in to implement (the plug-in is simple and easy to understand);

The simplest way is to upload through the "connect-multiparty" middleware.

Install by npm install connect-multiparty in the project.

Usage:

var multipart = require('connect-multiparty');
var multipartMiddleware = multipart();
app.post('/upload', multipartMiddleware, function(req, resp) {
 console.log(req.body, req.files);
 // don't forget to delete all req.files when done 
});

After uploading, the uploaded file will generate a temporary file in the temporary directory. You can print out req.files to view the specific file path.

Just move and rename the temporary file to the actual directory in the commented place to complete the upload function.

Simple.

Official address: https://www.npmjs.com/package/connect-multiparty

However, the official does not recommend using this middleware. It is recommended to use "multiparty" directly because error handling is more troublesome.

Let’s use “multiparty” to implement a version.

1. Use express (version 4.11.x) to create a project, using the default jade as the template engine.

2. In the project directory, install the necessary components through npm install multiparty.

3. Modify views/index.jade and make a simple form for file upload as follows.

 extends layout
  block content                       form(method='post', action='/file/uploading', enctype='multipart/form-data')
    input(name='inputFile', type='file', multiple='mutiple')
    input(name='btnUp', type='submit',value='上传')

4. Modify routes/index.js to implement the background code for uploading pages and uploading responses.

 var express = require('express');                                                                                                                      
  var router = express.Router();
  var multiparty = require('multiparty');
  var util = require('util');
  var fs = require('fs');
  /* 上传页面 */
  router.get('/', function(req, res, next) {
   res.render('index', { title: 'Express' });
 });
 /* 上传*/
 router.post('/file/uploading', function(req, res, next){
  //生成multiparty对象,并配置上传目标路径
  var form = new multiparty.Form({uploadDir: './public/files/'});
  //上传完成后处理
  form.parse(req, function(err, fields, files) {
   var filesTmp = JSON.stringify(files,null,);
   if(err){
    console.log('parse error: ' + err);
   } else {
    console.log('parse files: ' + filesTmp);
    var inputFile = files.inputFile[];
    var uploadedPath = inputFile.path;
    var dstPath = './public/files/' + inputFile.originalFilename;
    //重命名为真实文件名
    fs.rename(uploadedPath, dstPath, function(err) {
     if(err){
      console.log('rename error: ' + err);
     } else {
      console.log('rename ok');
     }
    });
   }
   res.writeHead(, {'content-type': 'text/plain;charset=utf-'});
   res.write('received upload:\n\n');
   res.end(util.inspect({fields: fields, files: filesTmp}));
  });
 });
 module.exports = router;

Done. This completes the introduction to the file upload function based on nodejs express (4.x). I hope it will be helpful for everyone to learn nodejs express related knowledge.

Statement
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
JavaScript in Action: Real-World Examples and ProjectsJavaScript in Action: Real-World Examples and ProjectsApr 19, 2025 am 12:13 AM

JavaScript's application in the real world includes front-end and back-end development. 1) Display front-end applications by building a TODO list application, involving DOM operations and event processing. 2) Build RESTfulAPI through Node.js and Express to demonstrate back-end applications.

JavaScript and the Web: Core Functionality and Use CasesJavaScript and the Web: Core Functionality and Use CasesApr 18, 2025 am 12:19 AM

The main uses of JavaScript in web development include client interaction, form verification and asynchronous communication. 1) Dynamic content update and user interaction through DOM operations; 2) Client verification is carried out before the user submits data to improve the user experience; 3) Refreshless communication with the server is achieved through AJAX technology.

Understanding the JavaScript Engine: Implementation DetailsUnderstanding the JavaScript Engine: Implementation DetailsApr 17, 2025 am 12:05 AM

Understanding how JavaScript engine works internally is important to developers because it helps write more efficient code and understand performance bottlenecks and optimization strategies. 1) The engine's workflow includes three stages: parsing, compiling and execution; 2) During the execution process, the engine will perform dynamic optimization, such as inline cache and hidden classes; 3) Best practices include avoiding global variables, optimizing loops, using const and lets, and avoiding excessive use of closures.

Python vs. JavaScript: The Learning Curve and Ease of UsePython vs. JavaScript: The Learning Curve and Ease of UseApr 16, 2025 am 12:12 AM

Python is more suitable for beginners, with a smooth learning curve and concise syntax; JavaScript is suitable for front-end development, with a steep learning curve and flexible syntax. 1. Python syntax is intuitive and suitable for data science and back-end development. 2. JavaScript is flexible and widely used in front-end and server-side programming.

Python vs. JavaScript: Community, Libraries, and ResourcesPython vs. JavaScript: Community, Libraries, and ResourcesApr 15, 2025 am 12:16 AM

Python and JavaScript have their own advantages and disadvantages in terms of community, libraries and resources. 1) The Python community is friendly and suitable for beginners, but the front-end development resources are not as rich as JavaScript. 2) Python is powerful in data science and machine learning libraries, while JavaScript is better in front-end development libraries and frameworks. 3) Both have rich learning resources, but Python is suitable for starting with official documents, while JavaScript is better with MDNWebDocs. The choice should be based on project needs and personal interests.

From C/C   to JavaScript: How It All WorksFrom C/C to JavaScript: How It All WorksApr 14, 2025 am 12:05 AM

The shift from C/C to JavaScript requires adapting to dynamic typing, garbage collection and asynchronous programming. 1) C/C is a statically typed language that requires manual memory management, while JavaScript is dynamically typed and garbage collection is automatically processed. 2) C/C needs to be compiled into machine code, while JavaScript is an interpreted language. 3) JavaScript introduces concepts such as closures, prototype chains and Promise, which enhances flexibility and asynchronous programming capabilities.

JavaScript Engines: Comparing ImplementationsJavaScript Engines: Comparing ImplementationsApr 13, 2025 am 12:05 AM

Different JavaScript engines have different effects when parsing and executing JavaScript code, because the implementation principles and optimization strategies of each engine differ. 1. Lexical analysis: convert source code into lexical unit. 2. Grammar analysis: Generate an abstract syntax tree. 3. Optimization and compilation: Generate machine code through the JIT compiler. 4. Execute: Run the machine code. V8 engine optimizes through instant compilation and hidden class, SpiderMonkey uses a type inference system, resulting in different performance performance on the same code.

Beyond the Browser: JavaScript in the Real WorldBeyond the Browser: JavaScript in the Real WorldApr 12, 2025 am 12:06 AM

JavaScript's applications in the real world include server-side programming, mobile application development and Internet of Things control: 1. Server-side programming is realized through Node.js, suitable for high concurrent request processing. 2. Mobile application development is carried out through ReactNative and supports cross-platform deployment. 3. Used for IoT device control through Johnny-Five library, suitable for hardware interaction.

See all articles

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

EditPlus Chinese cracked version

EditPlus Chinese cracked version

Small size, syntax highlighting, does not support code prompt function

PhpStorm Mac version

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools

MantisBT

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.