title: Angular: append query parameters to URL
body: <p>Im using this:</p>
  <pre class="lang-js prettyprint-override"><code>    import { HttpParams } from '@angular/common/http';
      let params = new HttpParams();
      params.append('newOrdNum','123');
  </code></pre>
  <p>But this is not working, i dont append param in url. Any suggestion?</p>