basic keywords or variables in nodejs |node js tutorials

 

globals

_dirname

_filename

require

module

process

 

any where u can access that varaivble is called global variables

in app.js

setInterval()

setinterval(()=>{},1000)

setinterval(()=>{

console.log('helloworld')},1000)

call back funciton is conole.log

to understand the code is easy - divide whole program into parts

write a function in es6

const sayHi =()=> {}

const sayHi = (name) => {

console.log('hello ${name}');

}

sayHi('susam');

const john ='hon';

sayHi(john)

fucntion sayHi(name)

{

console.log'hellow name');

}

every file in node is module

modules -encapsulated code ( only share minimum)

it will print that page

console.log(module);

local varoables and global varaiables

glaobl to uise in another module they are using export that required varaible

multiple exports

in impoer names.john, names.peter

if we  export any variable - it can cal it as global variable

require(modules locatioion)

single export

module.exports = sayHi

instant export

module.exports.items = ['item1','item2'];

const person = {

name :'bpb',

}

module.exports.singlePerson = person;

without export

output

input

7-mind-grenade.js

node js documentation - https://nodejs.org/dist/latest-v14.x/docs/api/http.html

i ssen in one lecture -

varaible declaration 

used in fucntion 

run this page

after taht 

varaible declaration in page

functin in one page

import in one page

run that page

use built in modules

info about current user

https://www.w3schools.com/nodejs/ref_modules.asp

current os type release totalmem

const path = require('path')

path module;

path.sep -> console .log

path.join('/content','subfolder','test.txt');

path.basename