DateRange and IntRange class. DateRange sample contains group "PriceRow" by date!

DateRange.cs

void Main()
{
  List<PriceRow> prs = new List<PriceRow>{
		new PriceRow{
			BeginDate = DateTime.Now.Date,
			EndDate = DateTime.Now.Date.AddDays(5),
			Price = 5000,
		},
		new PriceRow{
			BeginDate = DateTime.Now.Date.AddDays(1),
			EndDate = DateTime.Now.Date.AddDays(3),
			Price = 3000,
		},
	};
	var q = from pr in prs
			from date in new DateRange(pr.BeginDate, pr.EndDate)
			group pr by date into g
			select new {
				Date = g.Key,
				Price = g.Min(pr => pr.Price),
			};
			
	foreach(var d in q)
	{
		Console.WriteLine(d);
	}
}

public class PriceRow
{
	public DateTime BeginDate {get;set;}
	public DateTime EndDate {get;set;}
	public int Price {get;set;}
}

// Define other methods and classes here
public class DateRange : IEnumerable<DateTime>
{
    private DateTime _beginDate;

    private DateTime _endDate;

    public DateRange(DateTime beginDate, DateTime endDate)
    {
        _beginDate = beginDate;
        _endDate = endDate;
    }

    System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
    {
        return this.GetEnumerator();
    }

    public IEnumerator<DateTime> GetEnumerator()
    {
        for (DateTime date = this._beginDate; date <= this._endDate; date = date.AddDays(1))
        {
            yield return date;
        }
    }
}

IntRange.cs

/// <summary>
/// Range
/// http://stackoverflow.com/questions/8948205/doing-a-range-lookup-in-c-sharp-how-to-implement/8949322#8949322
/// </summary>
/// <typeparam name="TValue"></typeparam>
public class IntRange : IEnumerable<int>
{
    public IntRange(int min, int max)
    {
        this.Min = min;
        this.Max = max;
    }

    public int Max { get; set; }

    public int Min { get; set; }

    IEnumerator IEnumerable.GetEnumerator()
    {
        return this.GetEnumerator();
    }

    public IEnumerator<int> GetEnumerator()
    {
        for (int i = this.Min; i <= this.Max; i++)
        {
            yield return i;
        }
    }
}