c-sharp Get working hours within a time span

Question

Given multiple time span, how can I get an array that gives me number of working hours for a day.

The working hours start at 09:00 and end at 17:00

Examples:

1. 15-Nov-2017 16:00 - 17-Nov-2017 12:00 -> Should give me an array of [1,8,3]

2. 15-Nov-2017 09:00 - 17-Nov-2017 12:00 -> Should give me an array of [8,8,1] (This seems easy as I can do Hrs / 8 and Hrs % 8 to get the result.)

3. 16-Nov-2017 15:00 - 17-Nov-2017 15:00 -> Should give me an array of [2,6]

This is the method that currently gives me total working hours between the start time and end time:

protected double getWorkingHrs(DateTime _dtTaskStart, DateTime _dtTaskEnd)
{
    double count = 0;

    for (var i = _dtTaskStart; i < _dtTaskEnd; i = i.AddHours(1))
    {
        if (i.DayOfWeek != DayOfWeek.Saturday && i.DayOfWeek != DayOfWeek.Sunday)
        {
            if (i.TimeOfDay.Hours >= 9 && i.TimeOfDay.Hours < 17)
            {
                count++;
            }
        }
    }

    return count;
}

Any help would be appreciated.

Task showed like this in 8 hour blocks. So when I add a 20 Hour task, I have to break them down into sets and display them in the grid. I have to split them as chances are the task on different day might get assigned to a different user and may have different notes etc.

Cheers

Answer 1

Here is a solution for your problem:

    public static double[] GetWorkHours(DateTime start, DateTime end, TimeSpan workStartTime, TimeSpan workEndTime)
    {
        IList<double> result = new List<double>();

        if (start > end)
        {
            throw new ArgumentException("Start date is later than end date");
        }

        DateTime currentDate = start.Date;
        while (currentDate <= end.Date)
        {
            if (currentDate.DayOfWeek != DayOfWeek.Saturday && currentDate.DayOfWeek != DayOfWeek.Sunday)
            {
                TimeSpan realStartTime = GetStartTimeForDay(start, end, workStartTime, currentDate);
                TimeSpan realEndTime = GetEndTimeForDay(start, end, workEndTime, currentDate);

                if (realStartTime >= workEndTime || realEndTime <= workStartTime)
                {
                    result.Add(0);
                }
                else
                {
                    result.Add(GetHoursInTimePeriod(realStartTime, realEndTime));
                }
            }

            currentDate = currentDate.AddDays(1);
        }

        return result.ToArray();
    }

    private static TimeSpan GetStartTimeForDay(DateTime start, DateTime end, TimeSpan workStartTime, DateTime day)
    {
        return day == start.Date ? (start.TimeOfDay < workStartTime ? workStartTime : start.TimeOfDay) : workStartTime;
    }

    private static TimeSpan GetEndTimeForDay(DateTime start, DateTime end, TimeSpan workEndTime, DateTime day)
    {
        return day == end.Date ? (end.TimeOfDay < workEndTime ? end.TimeOfDay : workEndTime) : workEndTime;
    }

    private static double GetHoursInTimePeriod(TimeSpan start, TimeSpan end)
    {
        return (end - start).TotalHours;
    }

Answer 2

While not the prettiest (doing a ratcheting loop over datetimes by adding hours is a tad inelegant IMHO.), your function can be adapted to provide an enumerable with the number of working hours (or business hours as they are more commonly called) for each day as follows :

protected IEnumerable<double> getWorkingHrsPerDay(DateTime _dtTaskStart, DateTime _dtTaskEnd)
{
    double count = 0;
    DateTime lastHandledDate = _dtTaskStart.Date;
    for (var i = _dtTaskStart; i < _dtTaskEnd; i = i.AddHours(1))
    {
        if (i.DayOfWeek != DayOfWeek.Saturday && i.DayOfWeek != DayOfWeek.Sunday)
        {
            if (i.TimeOfDay.Hours >= 9 && i.TimeOfDay.Hours < 17)
            {
                count++;
            }
        }
        //if we have started to count the hours for a new day
        if (lastHandledDate.Date != i.Date)
        {
            lastHandledDate = i.Date;
            double hourCount = count;
            //reset our hour count
            count = 0;
            //we return the count of the last day
            yield return hourCount;
        }
        lastHandledDate = i.Date;
    }
}

you could then do the following with LINQ's ToArray method :

double[] hoursPerDay = getWorkingHrsPerDay(beginDate, endDate).ToArray();

Answer 3

If you want to have HOUR and Minutes use https://learn.microsoft.com/en-us/dotnet/api/system.timeonly?view=net-7.0
If you use older framework<6.0 install this package https://www.nuget.org/packages/Portable.System.DateTimeOnly

Here is it something which I did for stock market data in "date" is my current datetime the data which I work is from 8:30 to 16:00

        TimeOnly startTime = new TimeOnly(8, 30);
        TimeOnly endTime = new TimeOnly(16, 00);
        TimeOnly currentTime = new TimeOnly(date.Hour, date.Minute); 

        if (currentTime >= startTime && currentTime <= endTime)
        { //only data from 8:30 to 16.00
         
        }