node js基礎筆記

world

console.log('hello world')
//2.定時器
settimeout(()=>,3000)
//3.間隔定時
var time = 0
timer = setinterval(function()
},2000)

var counter = function(arr)

var adder = function(a,b)`
}var pi = 3.14
//1.直接匯出
module.exports = counter
//2.分別匯出
module.exports.counter = counter
module.exports.adder = adder
module.exports.pi = pi
//3.匯出物件
module.exports = 
//引用
var test=require('./count')

var events = require('events')

var myemitter = new events.eventemitter();
myemitter.on('someevent',function(message))
myemitter.emit('someevent','the event was emitted')

之後使用myemitter進行new出乙個物件

設定someevent這個事件為乙個函式

使用emit進行**函式

3.2.使用場景

var events = require('events')

var util = require('util');
var person = function(name)
util.inherits(person,events.eventemitter)
var xiaoming = new person('xiaoming')
var lili = new person('lili')
var lucy = new person('lucy')
var person = [xiaoming,lili,lucy]
person.foreach(function(person))
})xiaoming.emit('speak','xx')
lucy.emit('speak','sdsda')
lili.emit('speak','hello')

var fs = require('fs')

// 同步操作
var readtxt = fs.readfilesync('hellonode/txt','utf8')
fs.writefilesync('hellonode/write',readtxt)
//非同步操作
fs.readfile('hellonode/txt','utf8',(err,data)=>)

//建立刪除目錄

fs.unlink('hellonode/write',function())
fs.mkdirsync('hello')
fs.rmdirsync('hello')
fs.mkdir('hello',function())

var fs = require('fs')// 輸入輸出流也在fs

var myreadstream = fs.createreadstream('readme.txt')//建立讀取流
var data=''
myreadstream.on('data',function(chunk))
myreadstream.on('end',function())

var http = require('http');//匯入http

var fs = require('fs')//匯入fs
var rs = fs.createreadstream(__dirname + '/index.html')//返回檔案
rs.pipe(res)//使用管道輸出
})server.listen(3000,'127.0.0.1')//在3000埠啟動
console.log('server start on localhost port')

var server = require('./server');

var router = require('./route')
var handler = require('./handle')
var handle = {};//建立物件對映
handle["/"] = handler.home;
handle["/index"] = handler.home;
handle["/review"] = handler.review;
handle["/json"] = handler.json;
server.startserver(router.route,handle);//開啟服務

var server = http.createserver(onrequest)//建立乙個server

server.listen(3000,'127.0.0.1')//監聽3000埠

console.log('server start on localhost port')

}exports.startserver = startserver路由route.js

function route(pathname,handle,resp,params) else 

}exports.route = route

var fs = require('fs')

function home(res,params));
var rs = fs.createreadstream(__dirname + '/index.html');
rs.pipe(res);
}function review(res,params));
res.write('');
res.end();
}function json(res,params)
module.exports =

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