I have a basic Express code snippet that calculates the sum of two numbers:
const express = require('express')
const bodyParser = require('body-parser')
const app = express()
const port = 3000
app.use(bodyParser.urlencoded({ extended: true }))
app.get('/', (req, res) => {
res.sendFile(__dirname + "/index.html")
})
app.post("/", (req, res) => {
let n1 = req.body.num1 //these n1 and n2 are coming from inex.html
let n2 = req.body.num2
let result = Number(n1) + Number(n2)
res.send("" + result)
})
app.listen(port, () => {
console.log("Server is running at port 3000")
})
In res.send, when I removed the empty string and used only res.send(result), an error occurred:
RangeError [ERR_HTTP_INVALID_STATUS_CODE]: Invalid status code: 5
at new NodeError (node:internal/errors:372:5)
at ServerResponse.writeHead (node:_http_server:275:11)
at ServerResponse._implicitHeader (node:_http_server:266:8)
at ServerResponse.end (node:_http_outgoing:871:10)
at ServerResponse.send (C:\Users\Vandana Singh Bondil\OneDrive\Desktop\Lokesh\calculator\node_modules\express\lib\response.js:232:10)
at C:\Users\Vandana Singh Bondil\OneDrive\Desktop\Lokesh\calculator\calculator.js:17:9
at Layer.handle [as handle_request] (C:\Users\Vandana Singh Bondil\OneDrive\Desktop\Lokesh\calculator\node_modules\express\lib\router\layer.js:95:5)
at next (C:\Users\Vandana Singh Bondil\OneDrive\Desktop\Lokesh\calculator\node_modules\express\lib\router\route.js:144:13)
at Route.dispatch (C:\Users\Vandana Singh Bondil\OneDrive\Desktop\Lokesh\calculator\node_modules\express\lib\router\route.js:114:3)
at Layer.handle [as handle_request] (C:\Users\Vandana Singh Bondil\OneDrive\Desktop\Lokesh\calculator\node_modules\express\lib\router\layer.js:95:5)
Could someone explain why this error occurs?