title: Conversion of string into timespan with Sum
body: <p>Hi I have to execute a sum of hours, to do so I use the code c # below: first convert hourtot into timespan then I execute the total sum, at the end the total I get 08:30 which is impossible, how can I solve this? and what is it due to?</p>
  
  <p><strong>C# Code:</strong></p>
  
  <pre><code>    /*
      hourtot values:
      08:30
      10:00
      09:00
      08:30
      10:00
      10:30*/
  
  TimeSpan tot= TimeSpan.Zero;
   foreach (DataRow dr in dt.Rows)
   {
      String hourtot= r.CaricaOreGiornaliere(dr["date"].ToString());
      if(hourtot.Equals("00:00") == false)
      {
        TimeSpan hourcant= TimeSpan.Parse(hourtot.ToString());
        tot= tot+ hourcant;
      }
      }
     labelris.text = "" + tot.ToString(@"hh\:mm"); //this print 08:30
  </code></pre>