Create an array or List of all dates between two dates

Question

I am generating multi-series graphs with the date along the X-Axis. The problem is that not all of the series in the graph have the same dates in the date range. Meaning that if I choose 1 Feb through 30 Apr that one series may have data that starts at 1 Feb but only goes through the end of March but another series may have data for the entire date range. This skews the charts I need to create. Go, given the date range taken at the begining of the query I'd like to generate a list of dates and populate the data to be graphed, padding those series with 0's for those dates that have no data.

I hope that makes sense. Thanks,

Answer 1

LINQ:

Enumerable.Range(0, 1 + end.Subtract(start).Days)
          .Select(offset => start.AddDays(offset))
          .ToArray(); 

For loop:

var dates = new List<DateTime>();

for (var dt = start; dt <= end; dt = dt.AddDays(1))
{
   dates.Add(dt);
}

EDIT: As for padding values with defaults in a time-series, you could enumerate all the dates in the full date-range, and pick the value for a date directly from the series if it exists, or the default otherwise. For example:

var paddedSeries = fullDates.ToDictionary(date => date, date => timeSeries.ContainsDate(date) 
                                               ? timeSeries[date] : defaultValue);

Answer 2

public static IEnumerable<DateTime> GetDateRange(DateTime startDate, DateTime endDate)
{
    if (endDate < startDate)
        throw new ArgumentException("endDate must be greater than or equal to startDate");

    while (startDate <= endDate)
    {
        yield return startDate;
        startDate = startDate.AddDays(1);
    }
}

Answer 3

Our resident maestro Jon Skeet has a great Range Class that can do this for DateTimes and other types.