title: Add hours and minutes from textbox values in ASP.Net (c#)
body: <p>I have multpile textboxes holding calculated hours and minutes in the format HH:MM.
  At the bottom of my page I need a final textbox to total these hours and minutes,should this be done using Timespan?</p>
  
  <p>For clarification (and I know I haven't converted from string in the example below, this is just to show what I need to do)</p>
  
  <pre><code>txtTotalTime.Text = txtTimeTaken1.Text + txtTimeTaken2.Text + txtTimeTaken3.Text
  </code></pre>