when to use a body parser in express code example

Example 1: body parser express

//make sure it is in this order
npm i body-parser

const express = require('express')
const bodyParser = require('body-parser')

const app = express()

// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }))

// parse application/json
app.use(bodyParser.json())

app.use(function (req, res) {
  res.setHeader('Content-Type', 'text/plain')
  res.write('you posted:\n')
  res.end(JSON.stringify(req.body, null, 2))
})

Example 2: bodyparser purpose

//body-parser helps parse json files
//you can use body-parser anytime you need to use a form to post
//data to a request
var bodyParser = require("body-parser"); 
app.use(bodyParser.urlencoded({extended: true}));