Reading & Writing File in NodeJs

There are 2 ways to read files in node.js
1)Read synchronously:Used in the cases where file need to be read before any further processing . eg-any config file.
2)Read Asynchronously(Default):-read file in a separate thread. 

Read AsyncSynchronously
First we need to include file system object using require. Now we will call readFile method of file system.This has 2 parameters 
1)location of the file. 
2) callback function :This will notify us when we successfully read it.

console.log("--------Async Reading------------------");
console.log("Started Reading File...");
console.log("Reading File Asynchronously"); 
var content=fs.readFile('read.js',function(error,data)
 {
  if(error)
  {
   console.log(error);
  }
  else
  {
  console.log("Content \n "+data);
  }
 }
 );
console.log("-------- End Async Reading-------------");

First we need to include file system object using require. Now we will call readFileSync method of file system.This has one parameter -location of the file.

var fs=require('fs');
console.log("--------Synchronously Reading------------------");
console.log("Started Reading File...");
console.log("Reading File Synchronously"); 
var content=fs.readFileSync('read.js');
console.log("Content Printed First:-- \n "+content);
console.log("--------End Synchronously Reading--------------");