title: Obtain reference to element angular 4
body: <p>I have a component whos template looks like: </p>
  
  <pre><code>..blabla
   &lt;img md-card-image src=".."&gt;
  ..blabla
  </code></pre>
  
  <p>How do I obtain a reference inside my component.ts so that I could change it's src using angular 4?</p>