title: VB.net Get total time between two time spans
body: <p>I was wondering if there is a function with VB.NET that can tell me the total time that two different time spans have in common.</p>
  
  <p>for example, I have these two different time spans: </p>
  
  <pre><code>1st Date : (2013-01-01 8:30 AM) - (2013-01-01 11:30PM)
  2nd Date : (2013-01-01 10:00 PM) - (2013-01-02 6:00 AM)
  </code></pre>
  
  <p>Can VB.NET tell me that the answer is 1 hour and 30 mins? (perhaps in decimal)
  It is 1 hour and 30 minutes because up to 10:00PM in the evening and 11:30 in the evening falls in with the other time span.</p>
  
  <p><strong>Summary:</strong></p>
  
  <p>I just need a function that will tell me how many hours in a certain timespan is a part of the night shift. (that's 10:00 PM to 6:00 AM).</p>