Open the first node. JS Express Project

Manually creating an Express.js app can be broadly divided into the following steps:

1. Create a folder

A. Create a project root folder, such as Helloword

B. Create a directory structure for the project at the root of the project, creating {Public,public/css,public/img,public/js,db,views,views/includes,routes} in turn

You can use the command:

mkdir  {public,public/css,public/img,public/js,db,views,views/includes,routes}

2.NPM initialization and configuration of Package.json

A. Enter the console and enter the root directory of the project

B. Input command: NPM init, then enter some relevant parameters, name,version, etc. can refer to the following Package.json file

C. Use command: NPM install [email protected]--save

3. Declaration of dependency

Since Express.js is a contract-superior configuration, you can also enter the following directly into the Package.json, and then run the NPM install

{  "name": "HelloWorld",  "version": "0.0.1",  "description": "\" \ "" ",  " main ":" App.js ",  " scripts " : {    "start": "Node App.js"  },  "author": "",  "license": "ISC",  "dependencies": {    "express": " 4.1.2 "," Jade ":" 1.3.1 "," Mongoskin ":" 1.4.1 "," stylus ":" 0.44.0 "  }}

4.app.js Project Startup file configuration

Create the project start file app.js in the root directory, open app.js and edit

The configuration file for App.js mainly involves the following steps:

1) Introduction of dependency,

// dependency introduced var express = require (' Express '= require (' http '= require (' path ');

2) Setting the relevant configuration

Instantiation of Express.jsvar app = Express ();

Configuration port, views, views Engineapp.set (' Port ', Process.env.PORT | | |); App.set ("Views", Path.join (__dirname, ' views ')) ;//The __dirname underline here is two English underline app.set (' View engine ', ' Jade ');

3) Connect to database (optional)

4) Define Middleware

5) Defining routes

Define Route App.all ('/', function (req,res) {res.render (' index ', {msg: ' Welcome to the Practical node.js! '}); App.get ('/about ', function (req,res) {res.end (' about Us ');});

6) Create a service

Create a service Http.createserver (app). Listen (App.get (' Port '), function () {console.log (' Express.js server listening on port ' + App.get (' Port ');});

Before you start the service, you need to create a index.jade in the Views folder, with the following code:

H1 hellop= msg

7) Open Service

Typing in the command line: node app.js and entering http://localhost:3000/in the browser will get:

Entering http://localhost:3000/about in the browser will get:

5. Combining Jade

6. Run the project

Open the first node. JS Express Project