MERN Stack New Batch

  let express = require ( 'express' ) ; let app= express () ; app.get( '/' , function (req , res) { res. send ( 'Hello World' ) ; }) ; app.get( '/LogIn' , function (req , res) { res. send ( '<h1>LogIn Success</h1>' ) ; }) let server = app. listen ( 3022 ,function () { console . log ( 'Server Start' ) ; console . log ( "Example app listening at http://localhost:3022" ) })

  let fs = require ( "fs" ) ; // fs.writeFile("input.txt",'',function (error,fd) { // // }); // // fs.truncate("input.txt",function (error,fd) { // // }) //=======Delete File // fs.unlink("input.txt",function () { // // }) // fs.mkdir("Sabir",function () { // // }) // // fs.mkdir("Sabir/prem",function () { // // }) // if(fs.existsSync("Nayan")){ // MakeNaynFriend(); // }else { // fs.mkdir("Nayan",function () { // MakeNaynFriend() // // }); // } // fs.rmdir("Nayan/Prem",function () { // // }) //=====Remove all Dir fs . rm ( "Sabir" , { recursive : true, force : true } , (err) => { if (err) { console . error ( 'Error removing folder structure:' , err) ; } else { console . log ( 'Folder structure removed successfully' ) ; } }) ; function MakeNaynFriend () { fs . mkdir ( "Nayan/Prem" ,function (error , f...

  //create file if file is not create then create other open //read old data //insert new data //read all data let fs = require ( "fs" ) ; //create file if file is not create then create other open console . log ( "Step1" ) ; fs . open ( 'tejas.txt' , 'a+' ,function (error , data) { //error if (error){ console . log ( `Something is wrong for open file : ${error} ` ) ; return; } //read console . log ( "Step2---print old data" ) ; const buffer = Buffer . alloc ( 1024 ) ; fs . read (data , buffer , 0 , buffer. length , 0 , function (err , bytesRead) { if (err) { console . error ( 'Error reading file.' ) ; return; } if (bytesRead > 0 ) { console . log (buffer. toString ( 'utf8' , 0 , bytesRead)) ; } }) ; //insert new data console . log ( "Step3---New data append" ) ; fs . appendFile (data ,...

  let fs = require ( "fs" ) ; //======================Example 1=============== // fs.open("input.txt",'r',function (error,data) { // if(error){ // console.error('Error: File Not Found.'); // } // // /* // data receive integer value // * When you open a file using fs.open(), // * Node.js returns an integer value called // * a file descriptor. // * This is a low-level // * reference used by the // * operating system to access and // * manipulate the open file. // * // * */ // // console.log(`file descriptor=${data}`); // //============Read data in Chuck Format ======== // const buffer = Buffer.alloc(1024); // // fs.read(data, buffer, 0, buffer.length, 0, function(err, bytesRead) { // if (err) { // console.error('Error reading file.'); // return; // } // // if (bytesRead > 0) { // console.log('File Conten...

  let fs = require ( "fs" ) ; console . log ( "========= Synchronous ===" ) ; let data= fs . readFileSync ( 'input.txt' ) ; console . log (data. toString ( 'utf-8' )) ; console . log ( "========= Asynchronous ===" ) ; //read async fs . readFile ( "input.txt" ,function (error , data){ if (error){ console . log (error) } console . log (data) })

let fs = require ( "fs" ) ; let fileread= fs . createReadStream ( "input.txt" ) ; let filewrite= fs . createWriteStream ( "output.txt" ) ; fileread. pipe (filewrite) ; filewrite. on ( 'finish' , ()=>{ console . log ( "output.txt process complite" ) ; })

  let fs = require ( 'fs' ) ; let fileWrite= fs . createWriteStream ( 'Nayan.txt' ) ; fileWrite. write ( 'hi I am Nayan' , "utf-8" ) ; fileWrite. end () ; fileWrite. on ( 'finish' , ()=>{ console . log ( 'File Create Success' ) ; })