Shuffling a Generic List

Using the Fisher Yates Shuffle, the following was written by Rob Thijssen which I found pretty useful. He has made it an extension method which makes it simpler and pretty effective.

public static void Shuffle<T>(this IList<T> list)
{
    RNGCryptoServiceProvider provider = new RNGCryptoServiceProvider();
    int n = list.Count;
    while (n > 1)
    {
        byte[] box = new byte[1];

        do provider.GetBytes(box);
            while (!(box[0] < n * (Byte.MaxValue / n)));

        int k = (box[0] % n);
        n--;
        T value = list[k];
        list[k] = list[n];
        list[n] = value;
    }
}
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