title: Angular 2 + Ionic 2: Detect if an object was modified
body: <p><strong>Q) If I've got an object with loads of properties, all bound to fields in a form, how do I catch when the object has changed?</strong></p>
  
  <p>I don't want to put <code>(blur)</code> events on every field as the page is quite heavy already and this could lead to way too many listeners on the page.</p>
  
  <p>E.g</p>
  
  <p>Object:</p>
  
  <pre><code>var person = {
      name: string,
      email: string,
      phone: string
  };
  </code></pre>
  
  <p>Form:</p>
  
  <pre><code>&lt;input [(ngModel)]="person.name" type="text" /&gt;
  &lt;input [(ngModel)]="person.email" type="text" /&gt;
  &lt;input [(ngModel)]="person.phone" type="text" /&gt;
  </code></pre>