using System.Globalization;
public static void Main()
string[] crvArray = new string[] { null, null, "20161201" };
DateTime dt = DateTime.ParseExact(crvArray[2], "yyyyMMdd", CultureInfo.InvariantCulture, DateTimeStyles.None);
Console.WriteLine("day: " + dt.Day);
Console.WriteLine("month: " + dt.Month);
Console.WriteLine("year: " + dt.Year);