Most efficient way to randomly “sort” (Shuffle) a list of integers in C#

Question

I need to randomly \'sort\' a list of integers (0-1999) in the most efficient way possible. Any ideas?

Currently, I am doing something like this:

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Answer 1

We can make an extension method out of this to get a Random enumerator for any IList collection

class Program
{
    static void Main(string[] args)
    {
        IList l = new List();
        l.Add(7);
        l.Add(11);
        l.Add(13);
        l.Add(17);

        foreach (var i in l.AsRandom())
            Console.WriteLine(i);

        Console.ReadLine();
    }
}


public static class MyExtensions
{
    public static IEnumerable AsRandom(this IList list)
    {
        int[] indexes = Enumerable.Range(0, list.Count).ToArray();
        Random generator = new Random();

        for (int i = 0; i < list.Count; ++i )
        {
            int position = generator.Next(i, list.Count);

            yield return list[indexes[position]];

            indexes[position] = indexes[i];
        }
    }
}   

This uses a reverse Fisher-Yates shuffle on the indexes of the list we want to randomly enumerate through. Its a bit of a size hog (allocating 4*list.Count bytes), but runs in O(n).