how do i read a time value and then insert it into TimeSpan variables

string input = "08:00";
DateTime time;
if (!DateTime.TryParse(input, out time))
{
    // invalid input
    return;
}

TimeSpan timeSpan = new TimeSpan(time.Hour, time.Minute, time.Second);

TimeSpan span = new TimeSpan(days,hours,minutes,seconds,milliseonds);

DateTime time = new DateTime(year,month,day,minutes,seconds,milliseconds);

var span = new TimeSpan(hours, minutes, seconds);

var newSpan = span.Add(new TimeSpan(hours, minutes, seconds));