1. The first nodejs application
n1_hello.js
console.log('hello word!');
Execute the file in the command line cmd (Open the command line at this file):
node n1_hello.js
Return the result from cmd on the command line:
hello word!
2. Basic format of nodejs
//步骤一:引入require模块,require指令载入http模块 var http = require('http'); //步骤二:创建服务器 http.createServer(function (request, response) { // 发送 HTTP 头部 // HTTP 状态值: 200 : OK // 内容类型: text/html response.writeHead(200, {'Content-Type': 'text/html;chaset=utf-8;'}); //步骤三:接受请求与响应请求 if(request.url!=='/favicon.ico'){ ...... // 发送响应数据 response.end('');//必须有,没有则没有协议尾 } }).listen(8000); // 终端打印如下信息 console.log('Server running at http://127.0.0.1:8000/');
3. Nodejs calling function
----------------- Call local function--------------------------------
var http = require('http'); http.createServer(function (request, response) { response.writeHead(200, {'Content-Type': 'text/html;chaset=utf-8;'}); if(request.url!=='/favicon.ico'){ fun1(response); // 发送响应数据 response.end(''); } }).listen(8000); // 终端打印如下信息 console.log('Server running at http://127.0.0.1:8000/'); function fun1(res){ console.log('fun1'); res.write('hello,我是fun1'); }
-----------------Call external functions-----------------------------
Note: External functions must be written in module.exports, exports is the interface exposed by the module
------------(1) Only call one function- ----------
In the main program:
var http = require('http'); var otherfun = require("./models/otherfuns.js");//调用外部页面的fun2 http.createServer(function (request, response) { response.writeHead(200, {'Content-Type': 'text/html;chaset=utf-8;'}); if(request.url!=='/favicon.ico'){ otherfun(response);//支持一个函数时 response.end(''); } }).listen(8000); // 终端打印如下信息 console.log('Server running at http://127.0.0.1:8000/');
otherfuns.js
function fun2(res){ console.log('fun2'); res.write('你好!,我是fun2'); } module.exports = fun2;//只支持一个函数
------------(2) Call multiple functions-----------
Main program Medium:
var http = require('http'); var otherfun = require("./models/otherfuns.js");//调用写函数的外部页面otherfuns.js http.createServer(function (request, response) { response.writeHead(200, {'Content-Type': 'text/html;chaset=utf-8;'}); if(request.url!=='/favicon.ico'){ //todo 以对象.方法名调用 otherfun.fun2(response); otherfun.fun3(response); //todo 以字符串调用对应函数(结果同上) //otherfun['fun2'](response); //otherfun['fun3'](response); response.end(''); } }).listen(8000); // 终端打印如下信息 console.log('Server running at http://127.0.0.1:8000/'); }
otherfuns.js Medium
module.exports={ fun2:function(res){//匿名函数 console.log('fun2'); res.write('你好!,我是fun2');//在页面中输出 }, fun3:function(res){ console.log('fun3'); res.write('你好!,我是fun3'); }, ...... }
4. Preliminary nodejs routing
Main program n4_rout.js:
var http = require('http'); //引入url模块 var url = require('url'); http.createServer(function (request, response) { response.writeHead(200, {'Content-Type': 'text/html;chaset=utf-8;'}); if(request.url!=='/favicon.ico'){ var pathname = url.parse(request.url).pathname; pathname=pathname.replace(/\//,'');//替换掉前面的/ console.log(pathname); response.end(''); } }).listen(8000); // 终端打印如下信息 console.log('Server running at http://127.0.0.1:8000/');
Execute the file in the command line cmd, access: http://localhost:8000/, enter the routing address here, as shown below, and observe Command Line.
5. Nodejs reads files
Main program:
var http = require('http'); var optfile=require('./models/optfile');//导入文件 http.createServer(function (request, response) { // 发送 HTTP 头部 // HTTP 状态值: 200 : OK // 内容类型: text/html response.writeHead(200, {'Content-Type': 'text/html;chaset=utf-8;'}); if(request.url!=='/favicon.ico'){//清除第2次访问 optfile.readfileSync('./views/login.html');//同步调用读取文件readfileSync()方法 //optfile.readfile('./views/login.html',response);//异步步调用读取文件readfile()方法 response.end('ok!!!!!');//todo 不写没有协议尾 console.log('主程序执行完毕!'); } }).listen(8000); // 终端打印如下信息 console.log('Server running at http://127.0.0.1:8000/');
optfile In .js:
var fs=require('fs');//Node 导入文件系统模块(fs)语法 导入fs操作文件的类 module.exports={ readfileSync:function(path){ // 同步读取 var data = fs.readFileSync(path,'utf-8');//以中文读取同步文件路径path console.log("同步方法执行完毕。"); }, readfile:function(path){ // 异步读取 fs.readFile(path,function (err, data) { if (err) { console.error(err); }else{ console.log("异步读取: " + data.toString()); } }); console.log("异步方法执行完毕。"); }, }
Result: In command line cmd
(1) When reading the file synchronously:
(2) When reading files asynchronously: (commonly used)
In the web page: all are:
The above is the entire content of this article. I hope that the content of this article can bring some help to everyone's study or work. I also hope to support the PHP Chinese website!
For more articles related to nodejs basic applications, please pay attention to the PHP Chinese website!

Vercel是什么?本篇文章带大家了解一下Vercel,并介绍一下在Vercel中部署 Node 服务的方法,希望对大家有所帮助!

gm是基于node.js的图片处理插件,它封装了图片处理工具GraphicsMagick(GM)和ImageMagick(IM),可使用spawn的方式调用。gm插件不是node默认安装的,需执行“npm install gm -S”进行安装才可使用。

今天跟大家介绍一个最新开源的 javaScript 运行时:Bun.js。比 Node.js 快三倍,新 JavaScript 运行时 Bun 火了!

大家都知道 Node.js 是单线程的,却不知它也提供了多进(线)程模块来加速处理一些特殊任务,本文便带领大家了解下 Node.js 的多进(线)程,希望对大家有所帮助!

在nodejs中,lts是长期支持的意思,是“Long Time Support”的缩写;Node有奇数版本和偶数版本两条发布流程线,当一个奇数版本发布后,最近的一个偶数版本会立即进入LTS维护计划,一直持续18个月,在之后会有12个月的延长维护期,lts期间可以支持“bug fix”变更。

node怎么爬取数据?下面本篇文章给大家分享一个node爬虫实例,聊聊利用node抓取小说章节的方法,希望对大家有所帮助!


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

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Zend Studio 13.0.1
Powerful PHP integrated development environment

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

Dreamweaver Mac version
Visual web development tools

Atom editor mac version download
The most popular open source editor

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
