title: .net does ArrayList.Clear free up memory?
body: <p>I have a heavily populated arraylist, which I want to clear and reuse. If I clear it will it free up that previously used memory?</p>
  
  <p>I should also mention that the arraylist is a private read only field of a class that still has lots of active work to do after I use the arraylist first time round. So I can't wait for garbage collection after class goes out of scope.</p>
  
  <p>Is the Clear method fast enough? Or should I destroy and create a new arraylist?</p>
  
  <p>Question update:</p>
  
  <p>If I have field declared like this (thanks to Jon's advice)</p>
  
  <pre><code>    /// &lt;summary&gt;
      /// Collection of tasks.
      /// &lt;/summary&gt;
      private List&lt;Task&gt; tasks = new List&lt;Task&gt;();
  </code></pre>
  
  <p>then I populate it.... (heavily)</p>
  
  <p>Now if instead of clearing it and trimming, can I just call:</p>
  
  <pre><code>tasks = new List&lt;Task&gt;(); 
  </code></pre>
  
  <p>Would this be recommended?</p>