Sort string list with dates in C#

With linq:

var list = new List<string> {"01/01/2013", "10/01/2013", "20/01/2013"};
var orderedList = list.OrderByDescending(x => DateTime.Parse(x)).ToList();

UPDATE (according questions in comments):

You can treat invalid dates like this (invalid date is there treated as default(DateTime)):

var list = new List<string> { "01/01/2013", "10/01/2013", "N/A" , "20/01/2013"  };
var orderedList2 = list.OrderByDescending(x =>
            {
                DateTime dt;
                DateTime.TryParse(x, out dt);
                return dt;
            });

Or if you want to have invalid datetime as first item in the list:

var orderedList3 = list.OrderByDescending(x =>
            {
                DateTime dt;
                if (!DateTime.TryParse(x, out dt)) return DateTime.MaxValue;
                return dt;
            }); 

You can also filter the invalid dates out:

var filteredList = list.Where(x =>
            {
                DateTime dt;
                return DateTime.TryParse(x, out dt);
            }).Select(DateTime.Parse).OrderByDescending(x => x);

Or even better:

var filteredList = list.Select(x =>
        {
            DateTime dt;
            return new {valid = DateTime.TryParse(x, out dt), date = dt};
        }).Where(x => x.valid).Select(x => x.date).OrderByDescending(x => x);

You shouldn't use string representations of data - we're all living in object-oriented world :)

Best way would be to convert these strings into actual DateTime objects and sort them in reverse order via linq:

var dates = Array.ConvertAll(dateStrings, x => DateTime.Parse(x));
return dates.OrderByDesc(x => x);

Another way would be to implement custom sorting function, see this link. Then you'd just use it in a sort function:

DateAsStringComparer myComparer = new DateAsStringComparer();
dateStrings.Sort(myComparer);

Try this:

List<string> s = new List<string>() { "01/01/2013", "10/01/2013", "20/01/2013" };
var d = s.OrderByDescending(i => DateTime.ParseExact(i, "dd/MM/yyyy", null));