title: Angular 5 HTTP Get request Parameters - Send multiple objects
body: <p>I am trying to make an HTTP get request with an object as param. It's this possible?
  I already tried it multiple ways but without success. It works if I send only strings, not the entire class</p>
  
  <pre><code>export class City {
    id: number;
    name: string;
  }
  
    const params = new HttpParams().set('city', city)
    return this.http.get('http://localhost:3000/api/place/', {params})
  </code></pre>