title: Try catch and re-throw exception
body: <p>I saw some code the other day in one of our projects that uses a try catch and re-throws the caught exception like this:</p>
  
  <pre><code>try
  {
      exceptionProneCode();
  }
  catch(Exception ex)
  {
      throw ex;
  }
  </code></pre>
  
  <p>Nothing else was done with the exception in the catch block so I'm not even sure why it's re-thrown. I can't see any benefit to actually throwing the same exception again and doing nothing with the exception.</p>
  
  <p>If you re-throw an exception that's caught in the catch block, how does C# handle this? Does it get stuck in an infinite throw/catch loop? Or does it eventually leave the try catch?</p>