- Everything you write in node is a module
- You can export a function is a module using “module.exports”
- You can use a exported module using “require”
- Example below
MathsDemo.js
function add(a, b){
return a+b;
}
function subtract(a,b){
return a-b;
}
module.exports.add = add;
ExecuteMaths.js
mathObject = require("./MathsDemo.js");
var output = mathObject.add(10,20);
console.log('Result is : '+output);
Output :
Example : Writing data to a file
const fs = require('fs');
fs.writeFile('myfile', 'Hello World', (error)=>{
if(error) {
console.log('Error while saving data');
}
});
Example : Taking user input and storing data to file
const readline = require('readline'); //Read Line API
const fs = require('fs'); //File System API
const wirteToFile = (data) => {
fs.writeFile('myfile', `${data}`, error => {
if(error) {
console.log('Data has been saved');
}
});
};
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout
});
rl.question('Enter data ', (data) => {
wirteToFile(data);
rl.close();
});