Add Classes to Active Link in Laravel

Generally speaking, the easiest way to do this is comparing the name of the current route and the one you'd like to test against.

Luckily, Laravel's Illuminate\Support\Facades\Route class provides a nice currentRouteName() method that we can use to make a comparison.

Let's create a little function that you can re-use throughout your application.

use Illuminate\Support\Facades\Route;

function active_route(string $name): bool
{
    return Route::currentRouteName() === $name;
}

This function is great, but it doesn't do anything with classes. Let's add a second parameter so that a class string such as 'bg-gray-900' could be passed through.

use Illuminate\Support\Facades\Route;

function active_route(string $name, string $classes): bool
{
    if ($active = Route::currentRouteName() === $name) {
        echo $classes;
    }
  
    return $active;
}

Perfect! Now we can pass in the name of a route and a class string and it will echo the class if the current route matches the one provided.

If we wanted to, we could also wrap this into a custom Blade directive. In any ServiceProvider::boot(), add the following snippet:

Blade::directive('active', function ($expression) {
    return "<?php \active_route({$expression}); ?>"
});

Inside of a Blade template, we could now do:

@active('projects.index', 'bg-gray-900 hover:bg-gray-500')

And it would work just the same as calling active_route() directly. Nice!

Going beyond

One way this could be improved is conditionally checking whether or not a second parameter is passed through via the directive. This means you could treat @active as an if statement and do something based on the true and false conditions.

Let's make the second parameter to active_route() optional and add some checks to see how many parameters the directive receives:

use Illuminate\Support\Facades\Route;

function active_route(string $name, string $classes = null): bool
{
    if ($active = Route::currentRouteName() === $name && $classes) {
        echo $classes;
    }
  
    return $active;
}

use Illuminate\Support\Facades\Blade;

Blade::directive('active', function ($expression) {
    $parts = explode(',', str_replace(['(', ')'], '', $expression));
  
    if (count($parts) === 1) {
        return "<?php if (active_route({$expression})) : ?>";
    }
  
    return "<?php \active_route({$expression}); ?>"
});

It seems a bit confusing at first, but I'll break it down:

1. When our custom directive handler is called, it will receive $expression as a string. For example, @active('projects.index') will mean expression is ('projects.index'). The parentheses are included, so we need to remove those from the string before running explode().

2. explode(',', ...) will split the string after each ,. If two arguments are provided, then were should be a comma separating them. You could run into problems here if you use commas in your route names, but I've never seen anybody do that, most people use full-stops. In the case that no commas are present, $parts will just be an array with a single item.

3. If there is only 1 "part" (the length of $parts is 1), then we can assume that we're in if else mode, so we return an if statement instead of the string. Luckily, our active_route() function already returns a boolean, no matter the number of arguments received.

Now, we can do something like:

@active('projects.index') bg-gray-900 hover:bg-gray-500 @else bg-gray-400 @endif

@endactive vs. @endif

We've only got a single if statement, so using @endif is perfectly fine. If you wanted to make it a bit prettier, you could just add the following bit of code;

Blade::directive('endactive', function () {
    return '<?php endif; ?>';
});