How to get the smallest date from a list of objects with a date?

Question

I created a simple class that represents a project:

public class EntityAuftrag
{
    public string cis_auftrag { get; set; }
    public string bezeich { get; set; }
    public DateTime? dStart { get; set; }
    public DateTime? dEnd { get; set; }
    public decimal? aufstunde { get; set; }
    public int id_auftrag { get; set; }
    public string barcolor { get; set; }
}

Now I have a list of these. I want to extract the smallest date, how do I do that?

Answer 1

You can use Enumerable.Min (null values will be ignored unless all values are null):

DateTime? smallest = auftragList.Min(a => a.dStart);

Edit: if you want to find the object with the earliest(start) date, you can use OrderBy and First:

EntityAuftrag auft = auftragList.OrderBy(a => a.dStart).First();

If you want the latest date, you can use Enumerable.OrderByDescending instead.