The urlFor() application instance method lets you dynamically create URLs for a named route so that, were a route pattern to change, your URLs would update automatically without breaking your application. This example demonstrates how to generate URLs for a named route.
$app = new Slim();
//Create a named route
$app->get('/hello/:name', function ($name) use ($app) {
echo "Hello $name";
})->name('hello');
//Generate a URL for the named route
$url = $app->urlFor('hello', array('name' => 'Josh'));
In this example, $url is "/hello/Josh". To use the urlFor() application instance method, you must first assign a name to a route. Next, invoke the urlFor() application instance method. The first argument is the name of the route, and the second argument is an associative array used to replace the route’s URL parameters with actual values; the array's keys must match parameters in the route's URI and the values will be used as substitutions.