C# - Duration between two DateTimes in minutes

Question

I need to determine duration between two DateTimes in minutes.

However, there is a slight twist:

• exclude weekends
• only count minutes which a

Answer 1

Try the following DiffRange function.

public static DateTime DayStart(DateTime date)
{
    return date.Date.AddHours(7);
}

public static DateTime DayEnd(DateTime date)
{
    return date.Date.AddHours(19);
}

public static TimeSpan DiffSingleDay(DateTime start, DateTime end)
{
    if ( start.Date != end.Date ) {
        throw new ArgumentException();
    }

    if (start.DayOfWeek == DayOfWeek.Saturday || start.DayOfWeek == DayOfWeek.Sunday )
    {
        return TimeSpan.Zero;
    }

    start = start >= DayStart(start) ? start : DayStart(start);
    end = end <= DayEnd(end) ? end : DayEnd(end);
    return end - start;
}

public static TimeSpan DiffRange(DateTime start, DateTime end)
{
    if (start.Date == end.Date)
    {
        return DiffSingleDay(start, end);
    }

    var firstDay = DiffSingleDay(start, DayEnd(start));
    var lastDay = DiffSingleDay(DayStart(end), end);

    var middle = TimeSpan.Zero;
    var current = start.AddDays(1);
    while (current.Date != end.Date)
    {
        middle = middle + DiffSingleDay(current.Date, DayEnd(current.Date));
        current = current.AddDays(1);
    }

    return firstDay + lastDay + middle;
}