For an introduction to routing, see Basic routing. You define routing using methods of the Express app object that correspond to HTTP methods; for example, app. For a full list, see app. You can also use app. In fact, the routing methods can have more than one callback function as arguments.

With multiple callback functions, it is important to provide next as an argument to the callback function and then call next within the body of the function to hand off control to the next callback. A route method is derived from one of the HTTP methods, and is attached to an instance of the express class.

Express supports methods that correspond to all HTTP request methods: getpostand so on. There is a special routing method, app. Route paths, in combination with a request method, define the endpoints at which requests can be made.

Route paths can be strings, string patterns, or regular expressions. The characters? The hyphen - and the dot. Express uses path-to-regexp for matching the route paths; router for sign making java the path-to-regexp documentation for all the possibilities in defining route paths.

Express Route Tester is a handy tool for testing basic Express routes, although it does not support pattern matching. This route path will match abcdabbcdabbbcdand so on. This route path will match butterfly and dragonflybut router for sign making java butterflymandragonflymanand so on.

The captured values are populated in the req. To define routes with route parameters, simply specify the route router for sign making java in the path of the route as shown below.

Since the hyphen - and the dot. To have more control over the exact string that can be matched by a route parameter, you can append a regular expression router for sign making java parentheses :. In Express 4. This will likely be router for sign making java in Express 5.

You can provide multiple callback functions that behave like middleware to handle a request. The only exception is that these callbacks might invoke next 'route' to bypass the remaining route callbacks. Route handlers can be in the form of a function, an array of functions, or combinations of both, as shown in the following examples.

More than one callback function can handle a route make sure you specify the next object. For example:. The methods on the response object res in the following table can send a response to the client, and terminate the request-response cycle.

If none of these methods are called from a route handler, the client request will be left hanging. You can create chainable route handlers for a route path by using app.

Because the path is specified at a single location, creating modular routes is helpful, as is reducing redundancy and typos.

For more information about routes, see: Router documentation. Use the express. Router class to create modular, mountable route handlers.

The following example creates a router as a module, loads a middleware function in it, defines some routes, and mounts the router module on a path in the main app. Create a router file named birds. The following code is an example of a very basic route.