title: Laravel Route - Check if ID does not exist and show 404
body: <p>I don't want to show the page if the ID does not exist.</p>
  
  <p>How can I check this in my web.php routes in Laravel?</p>
  
  <p>I currently have the following route:</p>
  
  <pre><code>Route::get('/public/{project_id}', 'ProjectController@public');
  </code></pre>
  
  <p>How can I do a conditional check to see if project_id exists?</p>
  
  <p>I saw there was an option for <a href="https://laravel.com/docs/5.8/routing" rel="nofollow noreferrer">Route::bind</a> in the routing docs -- is that a solution? Thanks</p>
  
  <p>Update Note: Slightly different than the Laravel 4 approach as binding seems to have been baked in to the route class.</p>