title: Use array of a component in another component in angular2
body: <p>I have an array declared public like : </p>
  
  <pre><code>public arr: Array&lt;any&gt; = [] 
  </code></pre>
  
  <p>in AddUserComponent which stores the name of users. </p>
  
  <p>i need this array to be used in another component AddTopicComponent to display the user's names as a dropdown. </p>
  
  <p>How do i use this array values in AddTopicComponent ? these two components are not parent-child component.</p>