title: Angular2 ngModel binding in the third property level gets undefined
body: <p>A weird thing is happening on my form or maybe i am not doing it right, let me explain to you by presenting my code.</p>
  
  <p>i have defined a form object inside my component</p>
  
  <pre><code>form = {};
  </code></pre>
  
  <p>There is a button on each row with data that when you click it opens a modal widow and also passes the item as argument.</p>
  
  <pre><code>&lt;a class="btn btn-warning" (click)="open(item)"&gt;&lt;i class="glyphicon glyphicon-pencil"&gt;&lt;/i&gt;&lt;/a&gt;
  </code></pre>
  
  <p>This is the method that fires and opens a modal window but also assign the item object to form object above:</p>
  
  <pre><code>open = (item: any) =&gt; {
      this.inventoryEditModal.open(); //Opens a modal window
  
      this.form = item; // the assignment 
  }
  </code></pre>
  
  <p>The item object is available on the view by printing it out like this:</p>
  
  <pre><code>{{ form | json }} // i can see all item properties
  </code></pre>
  
  <p>The modal window contains a form where user will edit the item, so basically the input form fields should get filled with item properties values but for some reason the third level is undefined and i don't understand why, let me show you an screenshot of the second level</p>
  
  <pre><code>&lt;input type="text" class="form-control" [(ngModel)]="form.alarmSystem" name="wireless"&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/Herhk.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Herhk.png" alt="enter image description here"></a></p>
  
  <p>The third level gets undefined:</p>
  
  <pre><code>&lt;input type="text" class="form-control" [(ngModel)]="form.alarmSystem.wireless" name="wireless"&gt;
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/cG3x8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cG3x8.png" alt="enter image description here"></a></p>
  
  <p>This issue is happening only for the third level "object.object.property". I am only showing one input field but the form contains more than 8 fields they all have same issue.</p>
  
  <p>Not sure what i am missing here, but logically it should work. Do you have see this issue happening here and there or experienced your self? </p>
  
  <p>Thank you in advance.</p>