Description: A route parameter in web application frameworks like Express.js is a variable part of the URL that allows capturing specific values from it. These parameters are fundamental for building dynamic web applications, as they enable developers to extract information from HTTP requests easily and efficiently. Route parameters are defined in the application’s route using a colon (:) followed by the parameter name. For example, in the route ‘/user/:id’, ‘id’ is a route parameter that can capture any value passed in that position of the URL. This means that if a user accesses ‘/user/123’, the value ‘123’ can be retrieved and used within the application’s logic. Route parameters are especially useful in RESTful applications, where accessing specific resources through unique identifiers is required. Additionally, they allow for greater flexibility and customization in route management, facilitating the creation of APIs and interaction with databases. In summary, route parameters are an essential tool in web development that contributes to the creation of interactive and customized web applications.
Uses: Route parameters are primarily used in web applications to capture dynamic information from URLs. They are especially common in the development of RESTful APIs, where they allow access to specific resources through unique identifiers. They are also used in applications that require customization in navigation, such as user profiles, products in a catalog, or any resource that needs to be uniquely identified in the URL.
Examples: A practical example of a route parameter in Express.js would be defining a route to get information about a specific user: app.get(‘/user/:id’, (req, res) => { const userId = req.params.id; // logic to get the user by userId }); In this case, if a user accesses ‘/user/42′, the value ’42’ will be captured as the user ID and can be used to perform database queries or return specific information to the client.
