[Solved] Why does req.body remain undefined in this Express app? const express = require('express'); const app = express(); app.post('/submit', (req, res) => { console.log(req.body); res.send('Done'); }); app.... | Node.js

Node.js - HTTP Module

Why does req.body remain undefined in this Express app?

const express = require('express');
const app = express();

app.post('/submit', (req, res) => {
  console.log(req.body);
  res.send('Done');
});

app.listen(3000);

ABecause the server is not listening on port 3000.

BBecause the route path is incorrect.

CBecause the app is missing middleware to parse the request body.

DBecause console.log cannot print req.body.

Step-by-Step Solution

Solution:

Step 1: Check middleware usage
The app does not use express.json() or express.urlencoded(), so request bodies are not parsed.
Step 2: Understand req.body behavior
Without parsing middleware, req.body is undefined because Express does not parse request bodies by default.
Final Answer:
Because the app is missing middleware to parse the request body. -> Option C
Quick Check:
Missing body parser middleware = D [OK]

Quick Trick: Always add body parser middleware to access req.body [OK]

Common Mistakes:

Assuming req.body is always available
Blaming route path or console.log
Ignoring middleware setup

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Why does req.body remain undefined in this Express app?

Step 1: Check middleware usage

Step 2: Understand req.body behavior

Final Answer:

Quick Check:

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