title: Does assigning null remove all event handlers from an object?
body: <p>I have defined new member in my class</p>
  
  <pre><code>protected COMObject.Call call_ = null;
  </code></pre>
  
  <p>This class has the following event handler that I subscribed to</p>
  
  <pre><code>call_.Destructed += new COMObject.DestructedEventHandler(CallDestructedEvent);
  </code></pre>
  
  <p>Will setting my member to null as following remove the event handler?</p>
  
  <pre><code>call_ = null;
  </code></pre>
  
  <p>or I have to unsubscribed with -=?</p>