title: Formatting a negative TimeSpan
body: <p>I'm doing some math with the Timespans in .Net, and occasionally the sum results in a negative Timespan.  When I display the result I am having trouble formatting it to include the negative indicator.</p>
  
  <pre><code>Dim ts as New Timespan(-10,0,0)
  
  ts.ToString()
  </code></pre>
  
  <p>This will display "-10:00:00", which is good but I don't want to show the seconds so tried this.</p>
  
  <pre><code>ts.ToString("hh\:mm")
  </code></pre>
  
  <p>This returns "10:00" and has dropped the "-" from the front which is the crux of the issue.  My current solution is this:</p>
  
  <pre><code>If(ts &lt; TimeSpan.Zero, "-", "") &amp; ts.ToString("hh\:mm")
  </code></pre>
  
  <p>but I was hoping to accomplish the same by using only the format string.</p>