Express.js | express.Router和路由参数输入

Question

I have this issue with a little program I'm coding to practice Express.js.

I have a separate router which I want to send a response depending on the route. So if a go to "/santiago", it have to send "Hi Santiago", but right now it sends "Hi undefined". The code of the router name.js:

//name.js
const express = require('express');
const router = express.Router();

router.get('/', (req,res)=>{
    res.send("Hi " + req.params.name);
});

module.exports = router;

And here the code of app.js:

//app.js
const express = require('express');
const app = express();
let port = process.env.PORT || 3000;
app.listen(port);

const name = require('./name');

app.use('/:name', name);

app.get('/', (req,res)=>{
    res.send("Welcome");
});

What is wrong?

Answer 1

Your router doesn't get the parameter. Set the parameter on your name.js (router):

router.get('/:name', (req,res)=>{
    res.send("Hi " + req.params.name); 
});

And your root route on server.js:

app.use('/', name);

Basically your router will be called on root but expect a parameter.

This should fix your issue and 'Welcome' will still be printed on root. This is because the router expects a parameter so if not, your last app.get method will run.

Hope that helps !

Answer 2

You need to mark the param in the route. Try something like this:

app.get('/:name', (req,res) => {
    const { name } = req.params
    res.send("Hi " + name)
});