title: Close all open files handles with C#
body: <p>I have an integration/regression test suite I built on top of SpecFlow (which uses NUnit underneath).  The problem I am having is that sometimes there is an exception in a test and a file might remain open.  This is a problem in follow on tests because they cannot read/write to this file.</p>
  
  <p>Is there a way to detect what files a process has open and then close them all?</p>