title: Angular 2 Route params validation
body: <p>How can I validate Route params in Angular2?
  For example, I have a route:</p>
  
  <pre><code>{path: 'artist/:id', component: ArtistInfoComponent}
  </code></pre>
  
  <p>All I want is to check if parameter <code>id</code> is a valid number and if so, just show the component. Otherwise show a page with error message.</p>
  
  <p>I found Route Guards in Angular 2 but I think this isn't the best way to do validation because I can have many different params for different pages and writing individual Route Guard for all these pages isn't what I want. </p>
  
  <p>Is there a possibility to specify a regex for each route parameter?</p>
  
  <p><strong>UPD: Maybe there is a way to do a validation on query params? I mean  if I have such url: <code>/search?q=blablabla&amp;page=2</code> how can I check if the parameter <code>page</code> is valid? Is there a way to do it without Guards?</strong></p>