node. JS Learning Essays

One, the operation of CNMP;

1,CNMP Info jquery Query the version of jquery;

2,CNMP install [email protected];

3,CNMP list to query all downloaded content;

4,CNMP List | grep jquery; show only downloaded juery;

Second, in a certain JS file to enable the building server;

1, using ES5 to create the server;

var http=require ("http");

Http.createserver (function (req,res) {

Res.writehead (200,{"Content-type": "Text/html"});

Res.end ("Hello, world!") ");

}). Listen (8888);

Console.log ("Server running at http://127.0.0.2:8888/");

2, using ES6 to create the server;

Const Http=require ("http");

Const homename= "127.0.0.1";

Const port=3000;

Const Server=http.createserver (function (req,res) {

res.statuscode=200;

Res.setheader ("Content-type": "Text/plain");

Res.end ("Hello! ")；

});

Server.listen (Port,hostname, () =>{

Console.log ("Server created successfully! ")；

})；

Third, the use of commonjs;

1,

First, the HTTP module is introduced;

var http=require ("http");

2,

Then introduce the modules we need;

var util=require ("./util.js");//The file in the same directory to use./;

3,

Http.createserver (function (req,res) {

Res.writehead (200,{"Content-type": "Text/plain"; utf-8});

Util.say (res);//Must be the module introduced;

Util.add (res);//Must be the module introduced;

Res.end ();//res begins, and res ends;

}). Listen (8000);

Console.log ("Modified successfully! ");

Example!!!!

var http=require ("http");

var util=require ("./util.js");

Http.createserver (function (req,res) {

Res.writehead (200,{"Content-type": "Text/plain;charset=utf-8"});

Util.say (RES);

Util.add (RES);

Res.end ();

}). Listen (8000);

Console.log ("Hello! ");

var util={

Say:function (res) {

Res.write ("Nihao");

},

Add:function (res) {

Res.write (1+2+ "");

}

}

Module.exports=util;

A. Define the interface; If you use Var util={} When you define it, remember that it is the JSON format;

B. exposed interface; module.exports=util;

Iv. Use of NPM

1, global installation module; NPM Install N-g

2, project dependent, through--save add in

3, development dependence, the line does not need to---through--dev add in

4, view version ID: CNPM outdated

Five, protocol

Https://www.baidu.com:8080/api.php?from=1000phone&course=nodejs#test

{

Protocol: ' https: ',

Slashes:true,

Auth:null,

Host: ' www.baidu.com:8080 ',

Port: ' 8080 ',

Hostname: ' www.baidu.com ',

Hash: ' #test ',

Search: '? From=1000phone&course=nodejs ',

Query: {from: ' 1000phone ', Course: ' Nodejs '},

Pathname: '/api.php ',

Path: '/api.php?from=1000phone&course=nodejs ',

HREF: ' Https://www.baidu.com:8080/api.php?from=1000phone&course=nodejs#test '}

Six, event monitoring

var eventemitter=require ("Events");

Methods for defining an object in Es6: Class Player extends Eventemitter;

Instantiate a Player object: var player=new player ();

Listening process: Two

1, receive event---> can only have one receive event; Player.on ("Playing", (data) =>{

Console.log (' Playing: ${data} ');

});

2, the distribution of events----> can be distributed in multiple districts; Player.emit ("Playing", "Brief Encounter");

Playing ("playing", "sentiment in");

Seven, document management;

A total of 7 methods:

1, view file status, ()

var fs=require ("FS");

Fs.stat ("File name to view", (err,stats) =>{

if (err) {

Console.log (ERR)

}else{

Console.log (' Directory: ${stat.isdirectory ()} ');

Console.log (' File: ${stat.isfile ()} ');

}

})

2, create directory: Use Fs.mkdir;

3, write the file, and write the content, including a connection;

A: Start without files, create files and write content; fs.writefile;

Fs.writefile ("File path and name created", "Write File Contents", () =>{})

B: Start with file, write content only;

Fs.appendfile ("Write File path and name", "Write File Contents", () =>{})

4. Read file: Take advantage of Fs.readfile ("path and name of file", "Utf-8", () =>{});

If you do not write the second, you will see data returned as buffer type, but there will be an error if there is no such file;

5, read folder; Fs.readdir ("File name", (=>{});

6, file Rename; Fs.rename ("Original file name", "changed file name" () =>{});

7. Delete files (including two steps)

A: Delete the contents of the file;

Fs.readdirsync ("Deleted folder"). Map (item) =>{

Fs.unlink (' Deleted folder/${item} ', (ERR) =>{

if (err) {

Console.log (ERR)

}else{

Console.log ("Success! ")；

}

})

});

B: Delete a folder

Fs.rmdir ("Files to be deleted", (Err,data) =>{

if () {}else{};

})

eight, stream;

Since the 1,--save project

2,--save-dev since the development of the project;

3.pipe the output of the previous layer as the input of the next layer;

4.zlib compression module;

Zlib.creategzip ();

node. JS Learning Essays