Express.js – route parameters
In this article, we would like to show you how to use route parameters in Express.js.
Introduction
Route parameters are named URL segments that are used to get the values specified at their position in the URL. The received values are stored in the req.params
object, with the name of the route parameter specified in the path as their respective keys.
route path: /users/:id/request URL: http://localhost:5000/users/74req.params: { "id": "74" }
Practical example
In below example, we define route for users
with specified route parameter used get user by id
. For now we just use it to send back the parameter (req.params
).
const express = require('express');const app = express();app.get('/users/:id', (req, res) => { res.send(req.params); // send back the parameter});app.listen(5000);
Result:
Node.js / Express.js – server response
As you can see, we passed 12
as a user id
parameter and received proper req.params
object as a response.
Note:
The name of route parameters must be made up of “word characters” ([A-Za-z0-9_]).