Mastering Laravel Routing – Part 4

Laravel Route Parameters Tutorial

When defining routes, sometimes you need to capture parts of the URL (like user IDs or names). Laravel makes this simple with route parameters.

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Required Parameters

You can capture values from the URL by wrapping them in {} braces.

Route::get('/user/{id}', function (string $id) {
    return "User " . $id;
});

Visiting /user/5 will return:

User 5

You can also define multiple parameters:

Route::get('/posts/{post}/comments/{comment}', function (string $postId, string $commentId) {
    return "Post: $postId, Comment: $commentId";
});

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Parameters with Dependency Injection

If you need both services (like Request) and route parameters, always list dependencies first:

use Illuminate\Http\Request;

Route::get('/user/{id}', function (Request $request, string $id) {
    return "User " . $id . " with IP " . $request->ip();
});

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Optional Parameters

Sometimes, the parameter is not always required. Use ? and provide a default value:

Route::get('/user/{name?}', function (?string $name = 'John') {
    return $name;
});

/user → returns John
/user/Ali → returns Ali

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Regular Expression Constraints

You can restrict parameter values with regex using where:

Route::get('/user/{id}', function (string $id) {
    return "User ID: $id";
})->where('id', '[0-9]+'); // Only numbers allowed

/user/10 works, but /user/abc gives 404.

Multiple constraints:

Route::get('/user/{id}/{name}', function (string $id, string $name) {
    return "ID: $id, Name: $name";
})->where(['id' => '[0-9]+', 'name' => '[a-z]+']);

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Helper Methods for Constraints

Laravel provides shortcut methods for common patterns:

Route::get('/user/{id}', fn($id) => $id)->whereNumber('id');  
Route::get('/user/{name}', fn($name) => $name)->whereAlpha('name');  
Route::get('/user/{name}', fn($name) => $name)->whereAlphaNumeric('name');  
Route::get('/user/{id}', fn($id) => $id)->whereUuid('id');  
Route::get('/user/{id}', fn($id) => $id)->whereUlid('id');  

Restrict values to specific options:

Route::get('/category/{category}', fn($c) => $c)
     ->whereIn('category', ['movie', 'song', 'painting']);

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Global Constraints

If you always want a parameter (like id) to follow certain rules, define it globally in AppServiceProvider:

use Illuminate\Support\Facades\Route;

public function boot(): void
{
    Route::pattern('id', '[0-9]+');
}

Now, all {id} parameters in routes will only accept numbers.

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Encoded Forward Slashes

By default, / is not allowed in parameters. If you want to allow it (e.g., for search strings), use .*:

Route::get('/search/{search}', function (string $search) {
    return $search;
})->where('search', '.*');

/search/hello/world works
Note: Only works on the last route segment.

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Important

• {id} → Required parameter
• {name?} → Optional parameter
• where() → Add regex constraints
• whereNumber, whereAlpha, whereUuid, etc. → Built-in helpers
• Route::pattern() → Global constraints
• .* → Allow / in the last parameter